0001493152-23-007933 | 10-K | XBRL Viewer

Common Stock Warrants (Details Narrative) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Jun. 26, 2022
Issuance of warrants	483,380	1,554,826		467,242
Exercise price of warrants	$ 7.29			$ 3.00
Warrant expiration date				Dec. 26, 2022
Modification expense	$ 104
Exercise of placement agent warrant	1,067,242	135,650
Warrant exercised	$ 2,367	$ 806
Common Stock [Member]
Number of stock issued for exercise of stock warrants	632,231	94,808
Common stock issued		94,808	5,820,000
General and Administrative Expense [Member]
Modification expense	$ 244

Property and Equipment

12 Months Ended

Dec. 31, 2022

Property, Plant and Equipment [Abstract]

Property and Equipment

Note 4 – Property and Equipment

Property and equipment consist of the following:

Schedule of Property and Equipment

	December 31, 2022			December 31, 2021
Computer hardware and software	$	177		$	157
Furniture and fixtures		112			106
Equipment		52			132
Leasehold improvements		71			71
Construction in progress		12			—
Property and equipment, gross		424			466
Less: accumulated depreciation and amortization		(352	)		(351	)
Property and equipment, net	$	72		$	115

Depreciation expense for the years ended December 31, 2022, 2021 and 2020 was $66, $155 and $347, respectively.

Eton Pharmaceuticals, Inc.

NOTES TO FINANCIAL STATEMENTS

(in thousands, except share and per share amounts)

Cover - USD ($) $ in Millions	12 Months Ended
Cover - USD ($) $ in Millions	Dec. 31, 2022	Mar. 07, 2023	Jun. 30, 2022
Cover [Abstract]
Document Type	10-K
Amendment Flag	false
Document Annual Report	true
Document Transition Report	false
Document Period End Date	Dec. 31, 2022
Document Fiscal Period Focus	FY
Document Fiscal Year Focus	2022
Current Fiscal Year End Date	--12-31
Entity File Number	001-38738
Entity Registrant Name	ETON PHARMACEUTICALS, INC.
Entity Central Index Key	0001710340
Entity Tax Identification Number	37-1858472
Entity Incorporation, State or Country Code	DE
Entity Address, Address Line One	21925 W. Field Parkway
Entity Address, Address Line Two	Suite 235
Entity Address, City or Town	Deer Park
Entity Address, State or Province	IL
Entity Address, Postal Zip Code	60010-7278
City Area Code	(847)
Local Phone Number	787-7361
Title of 12(b) Security	Common Stock, $0.001 par value
Trading Symbol	ETON
Security Exchange Name	NASDAQ
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	true
Elected Not To Use the Extended Transition Period	true
Entity Shell Company	false
Entity Public Float			$ 51.5
Entity Common Stock, Shares Outstanding		25,458,057
Documents Incorporated by Reference [Text Block]	Portions of the registrant’s definitive proxy statement for its 2023 Annual Meeting of Stockholders, which the registrant intends to file pursuant to Regulation 14A with the Securities and Exchange Commission not later than 120 days after the registrant’s fiscal year ended December 31, 2022, are incorporated by reference into Part III of this Annual Report on Form 10-K
ICFR Auditor Attestation Flag	false
Auditor Firm ID	170
Auditor Name	KMJ Corbin & Company LLP
Auditor Location	Irvine, California

Common Stock Warrants

12 Months Ended

Dec. 31, 2022

Common Stock Warrants

Common Stock Warrants

Note 7 — Common Stock Warrants

Listed below is a summary of warrants outstanding as of December 31, 2022:

Summary of Warrants Outstanding

Description of Warrants	No. of Shares		Exercise Price
Placement Agent Warrants - IPO		414,000	$	7.50
SWK Warrants – Debt (Tranche #1)		51,239	$	5.86
SWK Warrants – Debt (Tranche #2)		18,141	$	6.62
Total		483,380	$	7.29 (Avg)

The holders of these warrants or their permitted transferees, are entitled to rights with respect to the registration under the Securities Act of their shares that are converted to common stock, including demand registration rights and piggyback registration rights. These rights are provided under the terms of a registration rights agreement between the Company and the investors.

On June 26, 2022, 467,242 warrants from the 2017 preferred stock offering with an exercise price of $3.00 were set to expire. Prior to the expiration, the Company entered into an agreement with the warrant holders, whereby it modified the terms of the warrants to extend the expiration date until December 26, 2022 in exchange for the Company retaining the option of a cashless exercise provision. No other terms were modified. Due to this modification, the Company incurred a modification expense of $244 that is included in general and administration expense on the Statement of Operations for the year ended December 31, 2022.

A rollforward of the warrants outstanding is listed in the table below:

	No. of Shares
Balance as of the beginning of the year		1,554,826
Exercise of Placement Agent Warrants – 2017 Preferred Stock Offering		(1,067,242	)
Expiration of Placement Agent Warrants – 2017 Preferred Stock Offering		(4,204	)
Balance as of the end of the year		483,380

There were 1,067,242 warrants exercised in 2022 resulting in 632,231 shares of common stock being issued by the Company. There were 135,650 warrants exercised in 2021 (all on a cashless basis) resulting in 94,808 shares of common stock being issued by the Company. The intrinsic value of the warrants exercised was $2,367 in 2022 and $806 in 2021.

Related-Party Transactions (Details Narrative) - USD ($)			1 Months Ended		9 Months Ended	12 Months Ended
	Feb. 18, 2019	Aug. 11, 2017	May 31, 2021	Apr. 30, 2021	Sep. 30, 2022	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Related Party Transaction [Line Items]
Proceeds from sale of machinery and equipment							$ 700,000
Payment of research and development expense						3,996,000	$ 6,235,000	$ 14,104,000
Imprimis Pharmaceuticals [Member]
Related Party Transaction [Line Items]
Proceeds from sale of machinery and equipment			$ 700,000
Gain on sale of lab equipment			$ 181,000
Eyemax [Member] \| Amended and Restated Agreement [Member]
Related Party Transaction [Line Items]
Sale of product expense	$ 2,000,000				$ 1,818,000
Eyemax [Member] \| One Milestone [Member] \| Amended and Restated Agreement [Member]
Related Party Transaction [Line Items]
Related party transaction	250,000
Eyemax [Member] \| Two Milestone [Member] \| Amended and Restated Agreement [Member]
Related Party Transaction [Line Items]
Related party transaction	$ 500,000
Harrow Health Inc [Member]
Related Party Transaction [Line Items]
Common Stock shares Owned						$ 1,982,000
Harrow Health Inc [Member] \| Ownership [Member]
Related Party Transaction [Line Items]
Equity Method Investment, Ownership Percentage				7.80%
Eyemax [Member]
Related Party Transaction [Line Items]
Related party transaction		$ 250,000
Payment of research and development expense		250,000
Sale of product expense		$ 500,000
Percentage of royalty fee		10.00%
Related party transaction, description		The Eyemax Agreement was for an initial term of 10 years from the date of the Eyemax Agreement, subject to successive two-year renewals unless the Company elected to terminate the Eyemax Agreement
Chief Executive Officer [Member] \| Restricted Stock [Member] \| Harrow Health Inc [Member]
Related Party Transaction [Line Items]
Stock Issued During Period, Shares, Issued for Services				25,000

Basic and Diluted Net Loss per Common Share

12 Months Ended

Dec. 31, 2022

Earnings Per Share [Abstract]

Basic and Diluted Net Loss per Common Share

Note 9 — Basic and Diluted Net Loss per Common Share

Basic and diluted net loss per share is computed using the weighted average number of shares of common stock outstanding during the period. Common stock equivalents (using the treasury stock and “if converted” method) from stock options, unvested RSAs and RSUs, and warrants at December 31, 2022, 2021, and 2020 were 5,494,153, 4,286,687 and 3,371,489, respectively, and are excluded from the calculation of diluted net loss per share because the effect is anti-dilutive. Included in the basic and diluted net loss per share calculation were RSUs awarded to directors that had vested, but the issuance and delivery of the shares are deferred until the director retires from service as a director.

The following table shows the computation of basic and diluted net loss per common share:

	Year ended December 31, 2022			Year ended December 31, 2021			Year ended December 31, 2020

Net loss	$	(9,021	)	$	(1,955	)	$	(27,970	)
Weighted average common shares outstanding (basic and diluted)		25,145,657			25,207,299			21,010,058
Net loss per common share (basic and diluted)	$	(0.36	)	$	(0.08	)	$	(1.33	)

Eton Pharmaceuticals, Inc.

NOTES TO FINANCIAL STATEMENTS

(in thousands, except share and per share amounts)

Debt (Details Narrative) $ / shares in Units, $ in Thousands							1 Months Ended		12 Months Ended
	Apr. 05, 2022	May 20, 2021 USD ($)	Aug. 11, 2020 USD ($)	Jul. 21, 2020 USD ($)	May 04, 2020 USD ($)	Nov. 13, 2019 USD ($)	Aug. 31, 2020 USD ($) $ / shares shares	Nov. 30, 2019 USD ($) $ / shares shares	Dec. 31, 2022 USD ($) $ / shares shares	Dec. 31, 2021 USD ($) shares	Dec. 31, 2020 USD ($)	Jun. 26, 2022 $ / shares shares
Debt Instrument [Line Items]
Borrowing amount			$ 2,000			$ 2,000
Warrants issued to purchase common stock \| shares									483,380	1,554,826		467,242
Warrants exercise price \| $ / shares									$ 7.29			$ 3.00
Interest expenses									$ 955	$ 1,042	$ 884
Debt discount amortization									127	148	121
Accrued interest									231	134
Proceeds from loan											511
Gain on debt extinguishment										365
PPP Loan [Member]
Debt Instrument [Line Items]
Interest expenses		$ 4
Proceeds from loan					$ 361
Gain on debt extinguishment										$ 365
EIDL Loan [Member]
Debt Instrument [Line Items]
Proceeds from loan				$ 150
London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
LIBOR interest rate	8.00%
Principal amount									$ 1,033
LIBOR Floor Rate [Member]
Debt Instrument [Line Items]
LIBOR interest rate	2.00%
Warrant [Member]
Debt Instrument [Line Items]
Borrowing amount							$ 2,000	$ 5,000
Warrants issued to purchase common stock \| shares							18,141	51,239
Warrants exercise price \| $ / shares							$ 6.62	$ 5.86
Warrants, fair value							$ 94	$ 226
Warrants expiration term							7 years	7 years
Warrant [Member] \| Measurement Input, Exercise Price [Member]
Debt Instrument [Line Items]
Warrants exercise price \| $ / shares							$ 6.85	$ 5.75
Warrant [Member] \| Measurement Input, Option Volatility [Member]
Debt Instrument [Line Items]
Warrant measurement input							95	95
Warrant [Member] \| Measurement Input, Expected Dividend Rate [Member]
Debt Instrument [Line Items]
Warrant measurement input							0	0
Warrant [Member] \| Measurement Input, Risk Free Interest Rate [Member]
Debt Instrument [Line Items]
Warrant measurement input							0.4	1.8
Food and Drug Administration's [Member]
Debt Instrument [Line Items]
Borrowing amount						3,000
SWK Credit Agreement [Member]
Debt Instrument [Line Items]
Proceeds amount						$ 5,000
Interest rate						5.00%
DebtInstrument description									The Company was required to maintain a minimum cash balance of $3,000, only pay interest on the debt until February 2022 and then pay 5.5% of the loan principal balance commencing on February 15, 2022 and then every three months thereafter until November 13, 2024 at which time the remaining principal balance is due. Borrowings under the SWK Credit Agreement are secured by the Company’s assets. The SWK Credit Agreement contains customary default provisions and covenants which include limits on additional indebtedness. In March 2020, SWK provided a waiver for the Company to obtain loans with the Small Business Association. In February 2021, the Company notified SWK that it will not require additional borrowing capacity under the SWK Credit Agreement and terminated the additional borrowing capacity with SWK
Minimum cash balance						$ 3,000
SWK Credit Agreement [Member] \| Unused lines of Credit [Member]
Debt Instrument [Line Items]
Interest rate						2.00%
SWK Credit Agreement [Member] \| London Interbank Offered Rate (LIBOR) Swap Rate [Member]
Debt Instrument [Line Items]
Interest rate						10.00%
SWK Credit Agreement [Member] \| Stated LIBOR Floor Rate [Member]
Debt Instrument [Line Items]
Interest rate						2.00%
SWK Credit Agreement [Member] \| Food and Drug Administration's [Member]
Debt Instrument [Line Items]
Proceeds amount						$ 5,000
SWK Credit Agreement [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Borrowing amount						$ 10,000

Liquidity Considerations

12 Months Ended

Dec. 31, 2022

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Liquidity Considerations

Note 2 — Liquidity Considerations

As of December 31, 2022, the Company had an accumulated deficit of $103,134 and for the year ended December 31, 2022 the Company had a net loss of $9,021.

To date, the Company has generated revenues from multiple products and expects further growth in 2023 and beyond in accordance with additional market penetration from these products plus revenues from additional products where it anticipates FDA approval. The Company currently believes its existing cash and cash equivalents of $16,305 as of December 31, 2022 will be sufficient to fund its operating expenses and capital expenditure requirements for at least the next twelve months from the date of issuance of these financial statements. This estimate is based on the Company’s current assumptions, including assumptions relating to estimated sales and its ability to manage its spending. The Company could use its available capital resources sooner than currently expected. Accordingly, the Company could seek to obtain additional capital through equity financings, the issuance of debt or other arrangements. However, there can be no assurance that the Company will be able to raise additional capital if needed or under acceptable terms, if at all. The sale of additional equity may dilute existing stockholders and newly issued shares may contain senior rights and preferences compared to currently outstanding common shares. The Company’s existing long-term debt obligation contains covenants and limits the Company’s ability to pay dividends or make other distributions to stockholders. If the Company experiences delays in product sales growth and completing its product development and obtaining regulatory approval for its other product candidates and is unable to obtain such additional financing, operations would need to be scaled back or discontinued.

Commitments and Contingencies

12 Months Ended

Dec. 31, 2022

Commitments and Contingencies Disclosure [Abstract]

Commitments and Contingencies

Note 14 — Commitments and Contingencies

Legal

The Company is subject to legal proceedings and claims that may arise in the ordinary course of business. The Company is not aware of any pending or threatened litigation matters at this time that may have a material impact on the operations of the Company.

License and Product Development Agreements

The Company has entered into various agreements in addition to those discussed above which are described below.

The three oral solution pediatric neurology product candidates discussed below, Topiramate, Zonisamide and Lamotrigine were developed by the Company and its various product candidate development partners and the Company subsequently sold all its rights and interests in these three products to Azurity in 2021. The Company has recognized $22,000 in milestone revenues to date from these three products (including $5,000 received in 2022) and may receive up to $20,000 in additional milestone revenues related to FDA product approvals and the future sales levels for the products. Azurity has assumed royalty or profit share obligations owed to development partners as well as additional milestone payments based on sales volume targets.

During the years ended December 31, 2021 and 2020 the Company worked with Tulex Pharmaceuticals, Inc. (“Tulex”) as a third-party contract manufacturer to develop an oral solution for Topiramate (fka ET-101) which targets a neurological condition. The Company subsequently filed the product with the FDA in October 2020 and paid a $1,438 filing fee. In November 2021, the product received approval from the FDA and was launched by Azurity in December 2021. The Company recognized a $5,000 milestone revenue at launch which was reflected in accounts receivable on the Company’s balance sheet at December 31, 2021 and subsequently collected in January 2022.

On January 23, 2019, the Company entered into a Licensing and Supply Agreement (the “Agreement”) with Liquimeds Worldwide (“LMW”) for Zonisamide oral liquid, a development stage product candidate (“ET-104”). Pursuant to the terms of the Agreement, the Company was to be responsible for regulatory and marketing activities and LMW was responsible for development and manufacturing of ET-104. The Company paid $650 to Azurity upon issuance of patent covering ET-104 listed in the FDA’s Orange Book in November 2022 and will pay $500 in the event that product sales in excess of $10,000 were achieved within a calendar year.

On June 12, 2019, the Company entered into an Exclusive Licensing and Supply Agreement (the “ET-105 License Agreement”) with Aucta Pharmaceuticals, Inc. (“Aucta”) for marketing rights in the United States to Lamotrigine, an oral suspension product candidate for use as an adjunct therapy for partial seizures, primary generalized tonic-clonic seizures, and generalized seizures of Lennox-Gastaut syndrome in patients two years of age and older. Pursuant to the terms of the ET-105 License Agreement, the Company was to be responsible for marketing activities and Aucta will be responsible for development, manufacturing, and regulatory activities related to obtaining regulatory approval. The Company paid Aucta a licensing payment of $2,000 in August 2019 upon receiving an acceptance for review letter from the FDA and will pay $2,450 upon FDA approval and commercial sales of the product candidate and another $1,000 upon issuance of an Orange-book listed patent. If Aucta successfully completes a Lamotrigine product line extension product, Eton will pay $1,500 upon FDA acceptance of the product filing. Aucta will be entitled to receive milestone payments from the Company of up to $3,000 based on commercial success of the product, including $1,000 when net sales exceed $10 million in a calendar year, and $2,000 when net sales exceed $20 million in a calendar year.

Eton Pharmaceuticals, Inc.

NOTES TO FINANCIAL STATEMENTS

(in thousands, except share and per share amounts)

Note 14 — Commitments and Contingencies (continued)

Azurity will assume royalty or profit share obligations owed to development partners as well as additional milestone payments based on sales volume targets.

On March 27, 2020, the Company entered into an Exclusive Licensing and Supply Agreement (the “Alkindi License Agreement”) with Diurnal for marketing ALKINDI SPRINKLE® in the United States. ALKINDI SPRINKLE®’s New Drug Application (NDA) was approved by the FDA on September 29, 2020 as a replacement therapy for pediatric patients with adrenocortical insufficiency.

For the initial licensing milestone fee, the Company paid Diurnal $3,500 in cash and issued 379,474 shares of its common stock to Diurnal which were valued at $1,264 based on the Company’s closing stock price of $3.33 on March 26, 2020 (see Note 6). The total amount of $4,764 was recorded as a component of research and development expense in the Company’s statement of operations for the year ended December 31, 2020. The Company will also pay Diurnal $2,500 if the product obtains orphan drug exclusivity status from the FDA.

On June 15, 2021, the Company acquired U.S. and Canadian rights to Crossject’s ZENEO® hydrocortisone needleless autoinjector, which is under development as a rescue treatment for adrenal crisis. The Company paid Crossject $500 upon signing, $500 in March 2022 upon a completion of a successful technical batch and could pay up to $3,500 in additional development milestones and up to $6,000 in commercial milestones, as well as a 10% royalty on net sales.

On October 28, 2021, the Company acquired the U.S. marketing rights to Carglumic Acid Tablets. The product’s Abbreviated New Drug Application (“ANDA”), which is owned by Novitium Pharma, was approved by the FDA on October 12, 2021. The product is an AB-rated, substitutable generic version of Carbaglu®. The Company paid $3,250 upon signing and retains 50% of the product profits with the balance being distributed to the licensor and manufacturer. The Company launched this product in December 2021.

In June 2022, the Company sold its rights in Cysteine Hydrochloride, Biorphen®, and Rezipres® to Dr. Reddy’s. Under the terms of the transaction, Dr. Reddy’s assumed immediate ownership of Eton’s rights and interest in the products. The Company received $5,000 at closing, recorded as licensing revenue in the twelve months ended December 31, 2022, and could receive up to $42,500 of additional payments based on the achievement of certain event-based and sales-based milestones. Of the $5,000 received at closing, $250 was held in escrow to address potential indemnity claims during the 12-month period following the effective date of the agreement. In addition, 10% of any additional payments paid by Dr. Reddy’s during the 12-month period following the effective date will be held in escrow and subsequently released to Eton upon expiration of the 12-month period following the effective date. In accordance with the terms of the agreement, $812 of Sintetica profit share receivables were expensed as cost of goods sold in the twelve months ended December 31, 2022.

On September 13, 2022, the Company acquired an FDA-approved ANDA for Betaine Anhydrous for oral solution. The ANDA was approved by the FDA on January 28, 2022. The Company paid $2,000 upon signing and could pay up to $1,000 in commercial milestones. The Company will retain 65% of the product profits with the balance being distributed to the licensor.

Indemnification

As permitted under Delaware law and in accordance with the Company’s Amended and Restated Bylaws, the Company is required to indemnify its officers and directors for certain events or occurrences while the officer or director is or was serving in such capacity. The Company is also party to indemnification agreements with its directors and officers. The Company believes the fair value of the indemnification rights and agreements is minimal. Accordingly, the Company has not recorded any liabilities for these indemnification rights and agreements as of December 31, 2022 or 2021.

Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2022	Dec. 31, 2021
Statement of Financial Position [Abstract]
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	50,000,000	50,000,000
Common stock, shares issued	25,353,119	24,626,004
Common stock, shares outstanding	25,353,119	24,626,004

Leases (Details Narrative) - USD ($) $ in Thousands	1 Months Ended			12 Months Ended
Leases (Details Narrative) - USD ($) $ in Thousands	Nov. 30, 2022	Nov. 30, 2020	Oct. 31, 2020	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Lease renewed description	In November 2022, the Company renewed its office lease for a two-year period through March 31, 2025	In November 2020, this laboratory lease was extended to June 2021	In October 2020, the Company renewed its office lease for a two-year period through March 31, 2023
Rights to use of assets	$ 188		$ 195	$ 188	$ 104
Operating lease liabilities	$ 188		$ 195	$ 182
Incremental borrowing rate				7.80%
Estimated discount rate percentage			5.40%
Estimated discount rate percentage	8.60%
Lease rent expense				$ 87	113	$ 139
Operating lease payments				88	83
Operating lease, right-of-use asset, amortization expense				$ 82	88	129
Operating lease, weighted average remaining lease term				2 years 3 months
Operating lease, weighted average discount rate				8.60%
Research and Development Expense [Member]
Operating lease cost				$ 0	9	55
General and Administrative Expense [Member]
Operating lease cost				$ 82	$ 86	$ 84

Schedule of Future Payments of Long Term Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Debt Disclosure [Abstract]
2023	$ 1,853
2024	6,595
Total payments	8,448
Less: amount representing interest	(1,833)
Loan payable, gross	6,615
Less: current portion of long-term debt	(1,033)	$ (1,418)
Less: unamortized discount	(198)
Long-term debt, net of unamortized discount	$ 5,384	$ 5,262

- Definition

Amount, excluding unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

+ References + Details

Basic and Diluted Net Loss per Common Share (Tables)

12 Months Ended

Dec. 31, 2022

Earnings Per Share [Abstract]

Computation of Basic and Diluted Net Loss Per Common Share

The following table shows the computation of basic and diluted net loss per common share:

	Year ended December 31, 2022			Year ended December 31, 2021			Year ended December 31, 2020

Net loss	$	(9,021	)	$	(1,955	)	$	(27,970	)
Weighted average common shares outstanding (basic and diluted)		25,145,657			25,207,299			21,010,058
Net loss per common share (basic and diluted)	$	(0.36	)	$	(0.08	)	$	(1.33	)

Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
Statements of Cash Flows - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Cash flows from operating activities
Net loss	$ (9,021)	$ (1,955)	$ (27,970)
Adjustments to reconcile net loss to net cash provided by (used in) operating activities:
Stock-based compensation	4,218	3,381	2,576
Common stock issued for product candidate licensing rights			1,264
Depreciation and amortization	1,774	462	651
Debt discount amortization	127	148	121
Gain on forgiveness of PPP loan		(365)
Gain on sale of equipment		(181)
Changes in operating assets and liabilities:
Accounts receivable	3,619	(5,423)	425
Inventories	(7)	692	(862)
Prepaid expenses and other assets	1,902	(1,026)	(20)
Accounts payable	(8)	(570)	1,769
Accrued liabilities	2,217	116	(300)
Net cash provided by (used in) operating activities	4,821	(4,721)	(22,346)
Cash used in investing activities
Proceeds from sale of equipment		700
Purchases of property and equipment	(38)	(9)	(50)
Purchase of product licensing rights	(2,750)	(3,250)
Net cash used in investing activities	(2,788)	(2,559)	(50)
Cash flows from financing activities
Proceeds from issuance of long-term debt, net of issuance costs			1,965
Proceeds from sales of common stock, net of offering costs			28,782
Proceeds from PPP and EIDL loans			511
Debt paydown	(385)	(150)
Proceeds from employee stock purchase plan and stock option and stock warrant exercises	251	541	367
Net cash (used in) provided by financing activities	(134)	391	31,625
Change in cash and cash equivalents	1,899	(6,889)	9,229
Cash and cash equivalents at beginning of year	14,406	21,295	12,066
Cash and cash equivalents at end of year	16,305	14,406	21,295
Supplemental disclosures of cash flow information
Cash paid for interest	730	815	797
Cash paid for income taxes
Supplemental disclosures of non-cash investing and financing activities:
Relative fair value of common stock warrants issued in connection with debt			94
Right-of-use assets obtained in exchange for lease liabilities	$ 188		$ 195

Commitments and Contingencies (Details Narrative) - USD ($) $ / shares in Units, $ in Thousands							1 Months Ended			12 Months Ended
	Sep. 13, 2022	Oct. 28, 2021	Jun. 15, 2021	Mar. 27, 2020	Jun. 12, 2019	Jan. 23, 2019	Mar. 31, 2022	Oct. 31, 2020	Mar. 31, 2020	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Mar. 26, 2020
Product Liability Contingency [Line Items]
Revenue recognized										$ 22,000
Additional milestone revenues										20,000
Research and development expense										3,996	$ 6,235	$ 14,104
Stock issued during period, value, new issues												28,782
Payments for licensing rights	$ 2,000	$ 3,250
Percentage of net profits payments to third party from sale of product	65.00%	50.00%
Revenues										21,251	21,832	39
Cost of goods sold										6,933	2,827	436
Payments for commercil milestones	$ 1,000
Dr Reddys [Member]
Product Liability Contingency [Line Items]
Held in escrow										250
Licensing And Supply Agreement [Member] \| Licensor [Member]
Product Liability Contingency [Line Items]
Research and development expense						$ 650
Licensing And Supply Agreement [Member] \| Licensor [Member] \| Product Sales [Member]
Product Liability Contingency [Line Items]
Research and development expense						500
Licensing And Supply Agreement [Member] \| Licensor [Member] \| Calendar Year [Member]
Product Liability Contingency [Line Items]
Research and development expense						$ 10,000
Tulex Pharmaceuticals Inc [Member]
Product Liability Contingency [Line Items]
Payment of filing fee								$ 1,438
Milestone payment amount											5,000
Aucta pharmaceuticals inc [Member] \| ET-105 License Agreement [Member]
Product Liability Contingency [Line Items]
Payments for Royalties					$ 2,000
Aucta pharmaceuticals inc [Member] \| ET-105 License Agreement [Member] \| Maximum [Member]
Product Liability Contingency [Line Items]
Milestone payment amount					3,000
Aucta pharmaceuticals inc [Member] \| ET-105 License Agreement [Member] \| Upon FDA approval [Member[
Product Liability Contingency [Line Items]
Payments for Royalties					2,450
Aucta pharmaceuticals inc [Member] \| ET-105 License Agreement [Member] \| Upon Issuance of Orange-book Listed Patent [Member]
Product Liability Contingency [Line Items]
Payments for Royalties					1,000
Aucta pharmaceuticals inc [Member] \| ET-105 License Agreement [Member] \| Upon FDA Acceptance of Product Filing [Member]
Product Liability Contingency [Line Items]
Payments for Royalties					$ 1,500
Aucta pharmaceuticals inc [Member] \| ET-105 License Agreement [Member] \| Sales Exceed $10 Million [Member]
Product Liability Contingency [Line Items]
[custom:MilestonePaymentDescription]					1,000 when net sales exceed $10 million in a calendar year
Aucta pharmaceuticals inc [Member] \| ET-105 License Agreement [Member] \| Sales Exceed $20 Million [Member]
Product Liability Contingency [Line Items]
[custom:MilestonePaymentDescription]					2,000 when net sales exceed $20 million in a calendar year
Diurnal Limited [Member]
Product Liability Contingency [Line Items]
Proceeds from sales of common stock, net of offering costs, shares									379,474
Stock issued during period, value, new issues									$ 1,264
Payment for obtaining product orphan drug										$ 2,500
Diurnal Limited [Member] \| Exclusive License and Supply Agreement [Member]
Product Liability Contingency [Line Items]
Cash paid for licensing milestone fee				$ 3,500
Proceeds from sales of common stock, net of offering costs, shares				379,474
Stock issued during period, value, new issues				$ 1,264
Shares issued, price per share													$ 3.33
Aggregate value of licensing milestone amount												4,764
Crossject S.A. [Member] \| Distribution and Promotion License Agreement [Member]
Product Liability Contingency [Line Items]
Research and development expense			$ 500				$ 500
Sale of stock, percentage										10.00%
Crossject S.A. [Member] \| Distribution and Promotion License Agreement [Member] \| Maximum [Member]
Product Liability Contingency [Line Items]
Cash paid for licensing milestone fee										$ 6,000
Crossject S.A. [Member] \| Distribution and Promotion License Agreement [Member] \| Upon FDA Acceptance of Product Filing [Member]
Product Liability Contingency [Line Items]
Research and development expense										3,500
Sintetica [Member] \| Dr Reddys [Member]
Product Liability Contingency [Line Items]
Cost of goods sold										812
Licensing Revenue [Member]
Product Liability Contingency [Line Items]
Revenue recognized										5,000
Revenues										10,000	19,000
Cost of goods sold										1,640	$ 1,500
Licensing Revenue [Member] \| Dr Reddys [Member]
Product Liability Contingency [Line Items]
Additional payment received										$ 42,500
Additional payment rate										10.00%
Licensing Revenues [Member] \| Dr Reddys [Member]
Product Liability Contingency [Line Items]
Revenues										$ 5,000

Computation of Basic and Diluted Net Loss Per Common Share (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Earnings Per Share [Abstract]
Net loss	$ (9,021)	$ (1,955)	$ (27,970)
Weighted average common shares outstanding (basic and diluted)	25,145,657	25,207,299	21,010,058
Net loss per common share (basic and diluted)	$ (0.36)	$ (0.08)	$ (1.33)

- Definition

The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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+ Details

Employee Savings Plan

12 Months Ended

Dec. 31, 2022

Retirement Benefits [Abstract]

Employee Savings Plan

Note 13 - Employee Savings Plan

The Company established an employee savings plan pursuant to Section 401(k) of the Internal Revenue Code, effective January 1, 2018. The plan allows participating employees to deposit into tax deferred investment accounts up to 100% of their salary, subject to annual limits. The Company makes certain matching contributions to the plan in amounts up to 4% of the participants’ annual cash compensation, subject to annual limits. For the years ended December 31, 2022, 2021 and 2020, the Company made $172, $154 and $117, respectively, in matching contributions.

Eton Pharmaceuticals, Inc.

NOTES TO FINANCIAL STATEMENTS

(in thousands, except share and per share amounts)

Common Stock (Details Narrative) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended				12 Months Ended
	Apr. 30, 2021	Oct. 31, 2020	Apr. 30, 2020	Mar. 31, 2020	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Subsidiary, Sale of Stock [Line Items]
Common stock, shares authorized					50,000,000	50,000,000
Common stock, par value					$ 0.001	$ 0.001
Value of common stock shares issued							$ 28,782
Warrant [Member]
Subsidiary, Sale of Stock [Line Items]
Number of stock issued for exercise of stock warrants					1,067,242
Common Stock [Member]
Subsidiary, Sale of Stock [Line Items]
Number of common stock shares issued						94,808	5,820,000
Value of common stock shares issued							$ 6
Stock issued during period shares stock options exercised					25,000	144,233	194,878
Shares issued, shares, share-based payment arrangement, after forfeiture							15,190
Number of stock issued for exercise of stock warrants					632,231
Employee Stock Purchase Plan [Member]
Subsidiary, Sale of Stock [Line Items]
Stock issued during period shares stock options exercised					69,884	49,155
RSA To New Employee [Member]
Subsidiary, Sale of Stock [Line Items]
Shares issued, shares, share-based payment arrangement, after forfeiture			15,190
Share based compensation arrangement by sharebased payment award purchase price of common stock percent	100.00%		25.00%
Board of Directors [Member] \| Restricted Stock Units (RSUs) [Member]
Subsidiary, Sale of Stock [Line Items]
Number of common stock shares issued	25,000
2018 Equity Incentive Plan [Member]
Subsidiary, Sale of Stock [Line Items]
Stock issued during period shares stock options exercised					25,000	144,233
IPO [Member]
Subsidiary, Sale of Stock [Line Items]
Number of common stock shares issued		3,220,000
Common stock share price per share		$ 7.00
Net cash proceeds from initial public offering		$ 21,026
Diurnal Limited [Member]
Subsidiary, Sale of Stock [Line Items]
Number of common stock shares issued				379,474
Value of common stock shares issued				$ 1,264
Securities Purchase Agreements [Member]
Subsidiary, Sale of Stock [Line Items]
Sale of stock, number of shares issued in transaction			2,600,000	2,600,000
Sale of stock, price per share			$ 3.00	$ 3.00
Proceeds from sale of stock, consideration received on transaction			$ 7,756	$ 7,756

Employee Savings Plan (Details Narrative) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Retirement Benefits [Abstract]
Percentage for tax deferred investment	100.00%
Percentage for matching contribution	4.00%
Employee saving plan for matching contribution	$ 172	$ 154	$ 117

Company Overview

12 Months Ended

Dec. 31, 2022

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Company Overview

Note 1 — Company Overview

Eton is an innovative pharmaceutical company focused on developing, acquiring, and commercializing innovative products to address unmet needs in patients suffering from rare diseases.

The Company currently has three FDA-approved rare disease products, ALKINDI SPRINKLE® for the treatment of adrenocortical insufficiency, Carglumic Acid for the treatment of hyperammonemia due to N-acetylglutamate synthase (NAGS) deficiency, and Betaine Anhydrous for the treatment of homocystinuria and has three additional product candidates in late-stage development. The Company is developing dehydrated alcohol injection, which has received Orphan Drug Designation for the treatment of methanol poisoning, ZENEO® hydrocortisone autoinjector for the treatment of adrenal crisis, and ET-400.

In addition, the Company is entitled to royalties or milestone payments from six FDA-approved products that the Company developed and out-licensed. The products are Alaway® Preservative Free, EPRONTIA®, Cysteine Hydrochloride, ZONISADE™, Lamotrigine, and Biorphen®.

Statements of Operations - USD ($) $ in Thousands	12 Months Ended
Statements of Operations - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Revenues:
Total net revenues	$ 21,251	$ 21,832	$ 39
Cost of Sales:
Total cost of sales	6,933	2,827	436
Gross profit (loss)	14,318	19,005	(397)
Operating expenses:
Research and development	3,996	6,235	14,104
General and administrative	18,582	14,265	12,610
Total operating expenses	22,578	20,500	26,714
Loss from operations	(8,260)	(1,495)	(27,111)
Other income (expense):
Interest and other income (expense), net	(761)	(1,006)	(859)
Gain on PPP loan forgiveness		365
Gain on equipment sale		181
Loss before income tax expense	(9,021)	(1,955)	(27,970)
Income tax expense
Net loss	$ (9,021)	$ (1,955)	$ (27,970)
Net loss per share, basic and diluted	$ (0.36)	$ (0.08)	$ (1.33)
Weighted average number of common shares outstanding, basic and diluted	25,145,657	25,207,299	21,010,058
Licensing Revenue [Member]
Revenues:
Total net revenues	$ 10,000	$ 19,000
Cost of Sales:
Total cost of sales	1,640	1,500
Product Sales And Royalties [Member]
Revenues:
Total net revenues	11,251	2,832	39
Cost of Sales:
Total cost of sales	$ 5,293	$ 1,327	$ 436

Summary of Significant Accounting Policies

12 Months Ended

Dec. 31, 2022

Accounting Policies [Abstract]

Summary of Significant Accounting Policies

Note 3 — Summary of Significant Accounting Policies

Basis of Presentation

The Company has prepared the accompanying financial statements in accordance with GAAP.

Eton Pharmaceuticals, Inc.

NOTES TO FINANCIAL STATEMENTS

(in thousands, except share and per share amounts)

Note 3 — Summary of Significant Accounting Policies (continued)

Use of Estimates

The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenue and expenses during the reporting periods. Significant estimates and assumptions reflected in these financial statements include, but are not limited to, provisions for uncollectible receivables, chargebacks and sales returns, valuation of inventories, useful lives of assets and the impairment of property and equipment, deferred tax assets, the accrual of research and development expenses and the valuation of common stock, stock options and warrants, and restricted stock units (“RSUs”). Estimates are periodically reviewed in light of changes in circumstances, facts and experience. Changes in estimates are recorded in the period in which they become known. Actual results could differ from those estimates or assumptions.

Segment Information

The Company operates the business on the basis of a single reportable segment, which is the business of developing and commercializing prescription drug products. The Company’s chief operating decision-maker is the Chief Executive Officer (“CEO”), who evaluates the Company as a single operating segment.

Cash and Cash Equivalents

The Company considers all highly liquid investments with an original maturity of three months or less to be cash equivalents. All cash and cash equivalents are held in U.S. financial institutions or invested in short-term U.S. treasury bills or high-grade money market funds. From time to time, amounts deposited with its bank exceed federally insured limits. The Company believes the associated credit risk to be minimal.

Accounts Receivable

Accounts receivable are recorded at the invoiced amount and are non-interest bearing. Accounts receivable are recorded net of allowances for doubtful accounts, cash discounts for prompt payment, distribution fees, chargebacks and returns and allowances. The total for these reserves amounted to $262 and $96 as of December 31, 2022 and 2021, respectively.

Inventories

The Company values its inventories at the lower of cost or net realizable value using the first-in, first-out method of valuation. The Company reviews its inventories for potential excess or obsolete issues on an ongoing basis and will record a write-down if an impairment is identified. Inventories at December 31, 2022 and 2021 consist solely of purchased finished goods. At December 31, 2022, inventories are shown net of a reserve for damaged Biorphen inventory yet to be destroyed and net of ALKINDI SPRINKLE® inventory at risk of expiry prior to being sold. At December 31, 2021, inventories are shown net of a reserve for Biorphen inventory due to the risk of expiry prior to being sold. There was an inventory reserve of $62 and $1,414 at December 31, 2022 and 2021, respectively.

Property and Equipment

Property and equipment are stated at cost. Depreciation of property and equipment is computed utilizing the straight-line method based on the following estimated useful lives. Computer hardware and software is depreciated over three years. Equipment, furniture and fixtures is depreciated over five years. Leasehold improvements are amortized over their estimated useful lives or the remaining lease term, whichever is shorter. Construction in progress is capitalized but not depreciated until it is placed into service.

Maintenance and repairs are charged to expense as incurred, while renewals and improvements are capitalized.

Eton Pharmaceuticals, Inc.

NOTES TO FINANCIAL STATEMENTS

(in thousands, except share and per share amounts)

Note 3 — Summary of Significant Accounting Policies (continued)

Intangible Assets

The Company capitalizes payments it makes for licensed products when the payment is based on FDA approval for the product and the cost is recoverable based on expected future cash flows from the product. The cost is amortized on a straight-line basis over the estimated useful life of the product commencing on the approval date in accordance with Accounting Standards Codification (“ASC”) 350 — Intangibles - Goodwill and Other. In November 2021, the Company purchased the rights for its Carglumic Acid product for $3,250 and that cost is being amortized over ten years. A $750 payment related to the approval of Biorphen had been capitalized in 2019 and that cost was being amortized over five years. As a result of the Biorphen sale to Dr. Reddy’s (see Note 14), amortization of that asset was accelerated to record $275 of expense in June 2022 and the remaining $75 of expense in the last six months of the year ended December 31, 2022. A $750 payment related to the approval of Rezipres® had been capitalized in Q1 2022 and that cost was being amortized over five years. As a result of the sale to Dr. Reddy’s, amortization of the Rezipres® asset was accelerated to record the remaining $738 in the three-month period ended June 30, 2022. In September 2022, the Company purchased the rights for its Betaine Anhydrous product for $2,000 and that cost is being amortized over five years. The intangible assets, net on the Company’s balance sheet reflected $1,996 of accumulated amortization as of December 31, 2022. The Company recorded $1,617, $204, and $150 of amortization expense for the years ended December 31, 2022, 2021, and 2020 respectively. During the years ended December 31, 2021 and 2020, the Company reclassified $204 and $150 of amortization expense of intangible assets, respectively, to cost of sales to conform with the current year presentation. The table below shows the estimated remaining amortization for these products for each of the five years from 2023 to 2027 and thereafter.


Year	Amortization Expense
2023	$	725
2024		725
2025		725
2026		725
2027		608
Thereafter		1,246
Total estimated amortization expense	$	4,754

Impairment of Long-Lived Assets

Long-lived assets are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. Recoverability of assets to be held and used is measured by a comparison of the carrying amount of an asset to estimated undiscounted future cash flows expected to be generated by the asset. If the carrying amount of an asset exceeds its estimated future cash flows, an impairment charge is recognized in the Company’s statements of operations for the amount by which the carrying amount of the asset exceeds the fair value of the asset. No impairment was recognized during the years ended December 31, 2022, 2021 and 2020.

Debt Issuance Costs and Debt Discount and Detachable Debt-Related Warrants

Costs incurred to issue debt are deferred and recorded as a reduction to the debt balance in the accompanying balance sheets. The Company amortizes debt issuance costs over the expected term of the related debt using the effective interest method. Debt discounts relate to the relative fair value of warrants issued in conjunction with the debt and are also recorded as a reduction to the debt balance and accreted over the expected term of the debt to interest expense using the effective interest method.

Eton Pharmaceuticals, Inc.

NOTES TO FINANCIAL STATEMENTS

(in thousands, except share and per share amounts)

Note 3 — Summary of Significant Accounting Policies (continued)

Leases

The Company accounts for leases in accordance with ASC Topic 842 — Leases. The Company reviews all relevant facts and circumstances of a contract to determine if it is a lease whereby the terms of the agreement convey the right to control the direct use and receive substantially all the economic benefits of an identified asset for a period of time in exchange for consideration. The associated right-of-use assets and lease liabilities are recognized at lease commencement. The Company measures lease liabilities based on the present value of the lease payments over the lease term discounted using the rate it would pay on a loan with the equivalent payments and term for the lease. The Company does not include the impact for lease term options that would extend or terminate the lease unless it is reasonably certain that it will exercise any such options. The Company accounts for the lease components separately from non-lease components for its operating leases.

The Company measures right-of-use assets based on the corresponding lease liabilities adjusted for (i) any prepayments made to the lessor at or before the commencement date, (ii) initial direct costs it incurs, and (iii) any incentives under the lease. In addition, the Company evaluates the recoverability of its right-of-use assets for possible impairment in accordance with its long-lived assets policy.

Operating leases are reflected on the balance sheets as operating lease right-of-use assets, current accrued liabilities and long-term operating lease liabilities. The Company does not have any finance leases as of December 31, 2022 and 2021.

The Company commences recognizing operating lease expense when the lessor makes the underlying asset available for use by the Company and the operating lease expense is recognized on a straight-line basis over the term of the lease. Variable lease payments are expensed as incurred.

The Company does not recognize right-of-use assets or lease liabilities for leases with a term of twelve months or less; such lease costs are recorded in the statements of operations on a straight-line basis over the lease term.

Patent Costs

All patent-related costs incurred in connection with filing and prosecuting patent applications are expensed as incurred due to the uncertainty about the successful award of a patent and the recovery of the expenditure. Amounts incurred are classified as general and administrative expenses.

Concentrations of Credit Risk, Sources of Supply and Significant Customers

The Company is subject to credit risk for its cash and cash equivalents which are invested in money market funds and U.S. treasury bills from time to time. The Company maintains its cash and cash equivalent balances with one major commercial bank and the deposits held with the financial institution exceed the amount of insurance provided on such deposits and is exposed to credit risk in the event of a default by the financial institutions holding its cash and cash equivalents to the extent recorded on the balance sheets. The Company believes the associated credit risk to be minimal.

The Company is dependent on third-party suppliers for its products and product candidates. In particular, the Company relies, and expects to continue to rely, on a small number of suppliers to manufacture key chemicals, approved products and process its product candidates as part of its development programs. These programs could be adversely affected by a significant interruption in the manufacturing process.

Eton Pharmaceuticals, Inc.

NOTES TO FINANCIAL STATEMENTS

(in thousands, except share and per share amounts)

Note 3 — Summary of Significant Accounting Policies (continued)

The Company is also subject to credit risk from its accounts receivable related to product sales as it extends credit based on an evaluation of the customer’s financial condition, and collateral is not required. Management monitors its exposure to accounts receivable by periodically evaluating the collectability of the account receivable based on a variety of factors including the length of time the receivables are past due, the financial health of the customer and historical experience. Based upon the review of these factors, the Company recorded no allowance for doubtful accounts at December 31, 2022 or 2021. The accounts receivable balance at December 31, 2022 and 2021 and product sales revenue recognized during the year ended December 31, 2022 and 2021 consist of sales to and amounts due from AmerisourceBergen Corporation, Cardinal Health Services and McKesson Corporation for sales of the Company’s Biorphen product. The December 31, 2022 accounts receivable balance and sales in 2022 also include amounts due from AnovoRx for sales of the Company’s ALKINDI SPRINKLE® product and its Carglumic Acid product. AnovoRx sales made up 45.5% of 2022 total net revenues and 79.8% of net accounts receivable as of December 31, 2022, and 9.0% of 2021 total net revenues and 6.4% of net accounts receivable as of December 31, 2021.

Revenue Recognition for Contracts with Customers

The Company accounts for contracts with its customers in accordance with ASC 606 — Revenue from Contracts with Customers. ASC 606 applies to all contracts with customers, except for contracts that are within the scope of other standards. Under ASC 606, an entity recognizes revenue when its customer obtains control of promised goods or services, in an amount that reflects the consideration which the entity expects to receive in exchange for those goods or services. To determine revenue recognition for arrangements that an entity determines are within the scope of ASC 606, the entity performs the following five steps: (i) identify the contract(s) with a customer; (ii) identify the performance obligations in the contract; (iii) determine the transaction price; (iv) allocate the transaction price to the performance obligations in the contract; and (v) recognize revenue when (or as) the entity satisfies a performance obligation.

At contract inception, once the contract is determined to be within the scope of ASC 606, the Company assesses the goods or services promised within each contract and determines those that are performance obligations and assesses whether each promised good or service is distinct. The Company then recognizes as revenue the amount of the transaction price that is allocated to the respective performance obligation when (or as) the performance obligation is satisfied. Arrangements that include rights to additional goods or services that are exercisable at a customer’s discretion are generally considered options. The Company assesses whether these options provide a material right to the customer and, if so, they are considered performance obligations. The exercise of a material right is accounted for as a contract modification for accounting purposes.

The Company recognizes as revenue the amount of the transaction price that is allocated to the respective performance obligation when (or as) each performance obligation is satisfied at a point in time or over time, and if over time this is based on the use of an output or input method. Any amounts received prior to revenue recognition will be recorded as deferred revenue. Amounts expected to be recognized as revenue within the twelve months following the balance sheet date will be classified as current portion of deferred revenue in the Company’s balance sheets. Amounts not expected to be recognized as revenue within the twelve months following the balance sheet date are classified as long-term deferred revenue, net of current portion.

Milestone Payments – If a commercial contract arrangement includes development and regulatory milestone payments, the Company will evaluate whether the milestone conditions have been achieved and if it is probable that a significant revenue reversal would not occur before recognizing the associated revenue. Milestone payments that are not within the Company’s control or the licensee’s control, such as regulatory approvals, are generally not considered probable of being achieved until those approvals are received.

Eton Pharmaceuticals, Inc.

NOTES TO FINANCIAL STATEMENTS

(in thousands, except share and per share amounts)

Note 3 — Summary of Significant Accounting Policies (continued)

Royalties – For arrangements that include sales-based royalties, including milestone payments based on a level of sales, which are the result of a customer-vendor relationship and for which the license is deemed to be the predominant item to which the royalties relate, the Company will recognize revenue at the later of (i) when the related sales occur, or (ii) when the performance obligation to which some or all of the royalty has been allocated has been satisfied or partially satisfied.

Significant Financing Component – In determining the transaction price, the Company will adjust consideration for the effects of the time value of money if the expected period between payment by the licensees and the transfer of the promised goods or services to the licensees will be more than one year.

The Company sells its ALKINDI SPRINKLE® and Carglumic Acid product to one pharmacy distributor customer which provides order fulfilment and inventory storage/distribution services. The Company may sell products in the U.S. to wholesale pharmaceutical distributors, who then sell the product to hospitals and other end-user customers. Sales to wholesalers are made pursuant to purchase orders subject to the terms of a master agreement, and delivery of individual shipments represent performance obligations under each purchase order. The Company uses a third-party logistics (“3PL”) vendor to process and fulfill orders and has concluded it is the principal in the sales to wholesalers because it controls access to the 3PL vendor services rendered and directs the 3PL vendor activities. The Company has no significant obligations to wholesalers to generate pull-through sales.

For its ALKINDI SPRINKLE® and Carglumic Acid products, the Company bills at the initial product list price which are subject to offsets for patient co-pay assistance and potential state Medicaid reimbursements which are recorded as a reduction of net revenues at the date of sale/shipment. Selling prices initially billed to wholesalers are subject to discounts for prompt payment and subsequent chargebacks when the wholesalers sell products at negotiated discounted prices to members of certain group purchasing organizations (“GPOs”) and government programs. Because of the shelf life of the product and the Company’s lengthy return period, there may be a significant period of time between when the product is shipped and when it issues credits on returned product.

The Company estimates the transaction price when it receives each purchase order taking into account the expected reductions of the selling price initially billed to the wholesaler/distributor arising from all of the above factors. The Company has developed estimates for future returns and chargebacks and the impact of other discounts and fees it pays, although ALKINDI SPRINKLE® and Carglumic Acid sales are not subject to returns. When estimating these adjustments to the transaction price, the Company reduces it sufficiently to be able to assert that it is probable that there will be no significant reversal of revenue when the ultimate adjustment amounts are known.

The Company stores its ALKINDI SPRINKLE® and Carglumic Acid inventory at its pharmacy distributor customer location, and sales are recorded when stock is pulled and shipped to fulfill specific patient orders. The Company recognizes revenue and cost of sales from products sold to wholesalers upon delivery to the wholesaler location. At that time, the wholesalers take control of the product as they take title, bear the risk of loss of ownership and have an enforceable obligation to pay the Company. They also have the ability to direct sales of product to their customers on terms and at prices they negotiate. Although wholesalers have product return rights, the Company does not believe they have a significant incentive to return the product.

Upon recognition of revenue from product sales, the estimated amounts of credit for product returns, chargebacks, distribution fees, prompt payment discounts, state Medicaid and GPO fees are included in sales reserves, accrued liabilities and net accounts receivable. The Company monitors actual product returns, chargebacks, discounts and fees subsequent to the sale. If these amounts end up differing from its estimates, it will make adjustments to these allowances, which are applied to increase or reduce product sales revenue and earnings in the period of adjustment.

In addition, the Company anticipates it will receive revenues from product licensing agreements where it has contracted for milestone payments and royalties from products it has developed or acquired.

Eton Pharmaceuticals, Inc.

NOTES TO FINANCIAL STATEMENTS

(in thousands, except share and per share amounts)

Note 3 — Summary of Significant Accounting Policies (continued)

Cost of Product Sales

Cost of product sales consists of the profit-sharing and royalty fees with the Company’s product licensing and development partners, the purchase costs for finished products from third-party manufacturers, the amortization of certain intangible assets, and freight and handling/storage costs from the Company’s 3PL logistics service providers. The cost of sales for profit-sharing and royalty fees and costs for purchased finished products and the associated inbound freight expense is recorded when the associated product sale revenue is recognized in accordance with the terms of shipment to customers while outbound freight and handling/storage fees charged by the 3PL service provider are expensed as they are incurred. Cost of sales also reflects any write-downs or reserve adjustments for the Company’s inventories.

Research and Development Expenses

Research and development (“R&D”) expenses include both internal R&D activities and external contracted services. Internal R&D activity expenses include salaries, benefits and stock-based compensation and other costs to support the Company’s R&D operations. External contracted services include product development efforts such as certain product licensor milestone payments, clinical trial activities, manufacturing and control-related activities and regulatory costs. R&D expenses are charged to operations as incurred. The Company reviews and accrues R&D expenses based on services performed and relies upon estimates of those costs applicable to the stage of completion of each project. Significant judgments and estimates are made in determining the accrued balances at the end of any reporting period. Actual results could differ from the Company’s estimates.

Upfront payments and milestone payments made for the licensing of technology for products that are not yet approved by the FDA are expensed as R&D in the period in which they are incurred. Nonrefundable advance payments for goods or services to be received in the future for use in R&D activities are recorded as prepaid expenses and are expensed as the related goods are delivered or the services are performed.

Income (Loss) Per Share

Basic net income (loss) per common share is computed by dividing net income (loss) attributable to common stockholders for the period by the weighted average number of common shares outstanding during the period. Diluted net income (loss) per share is computed by dividing the net income (loss) attributable to common stockholders for the period by the weighted average number of common and common equivalent shares, such as Series A Preferred, unvested restricted stock, stock options and warrants that are outstanding during the period. Common stock equivalents are excluded from the computation when their inclusion would be anti-dilutive. No such adjustments were made for 2022, 2021 or 2020 as the Company reported a net loss for the years ended December 31, 2022, 2021 and 2020 and including the effects of common stock equivalents in the diluted earnings per share calculation would have been anti-dilutive (see Note 9).

Stock-Based Compensation

The Company accounts for stock-based compensation under the provisions of ASC 718 Compensation — Stock Compensation. The guidance under ASC 718 requires companies to estimate the fair value of the stock-based compensation awards on the date of grant and record expense over the related service periods, which are generally the vesting period of the equity awards. The Company estimates the fair value of stock-based option awards using the Black-Scholes-Merton option-pricing model (“BSM”). The BSM requires the input of subjective assumptions, including the expected stock price volatility, the calculation of expected term, forfeitures and the fair value of the underlying common stock on the date of grant, among other inputs. The risk-free interest rate was determined from the implied yields for zero-coupon U.S. government issues with a remaining term approximating the expected life of the options or warrants. Dividends on common stock are assumed to be zero for the BSM valuation of the stock options. The expected term of stock options granted is based on vesting periods and the contractual life of the options. Expected volatilities are based on comparable companies’ historical volatility along with a limited weighting included for the Company’s own volatility, which management believes represents the most accurate basis for estimating expected future volatility under the current conditions. The Company accounts for forfeitures as they occur. The Company uses the closing common stock price on the date of grant for the fair value of the common stock.

Eton Pharmaceuticals, Inc.

NOTES TO FINANCIAL STATEMENTS

(in thousands, except share and per share amounts)

Note 3 — Summary of Significant Accounting Policies (continued)

Income Taxes

As part of the process of preparing the Company’s financial statements, the Company must estimate the actual current tax liabilities and assess temporary differences resulting from differing treatment of items for tax and accounting purposes. These differences result in deferred tax assets and liabilities, which are included within the balance sheets. The Company must assess the likelihood that the deferred tax assets will be recovered from future taxable income and, to the extent the Company believes that recovery is not likely, a valuation allowance must be established. To the extent the Company establishes a valuation allowance or increase or decrease to this allowance in a period, the impact will be included in income tax expense in the statements of operations. As of December 31, 2022 and 2021, the Company has established a 100% valuation reserve against its deferred tax assets.

The Company accounts for income taxes under the provisions of ASC 740 - Income Taxes. As of December 31, 2022 and 2021, there were no unrecognized tax benefits included in the balance sheets that would, if recognized, affect the effective tax rate. The Company’s practice is to recognize interest and penalties related to income tax matters in income tax expense. The Company had no accrual for interest or penalties in its balance sheets at December 31, 2022 or 2021, and has not recognized interest and penalties in the statements of operations for the years ended December 31, 2022, 2021 and 2020. As of December 31, 2022, the Company is subject to taxation in the United States and certain individual states – primarily Illinois and Tennessee. The Company’s tax losses from 2017 through 2022 are subject to examination by the federal and state tax authorities due to the carryforward of unutilized net operating losses (“NOLs”).

Current accounting standards include guidance on the accounting for uncertainty in income taxes recognized in the financial statements. Such standards also prescribe a recognition threshold and measurement model for the financial statement recognition of a tax position taken, or expected to be taken, and provides guidance on derecognition, classification, interest and penalties, accounting in interim periods, disclosure and transition. The Company believes that the ultimate deductibility of all tax positions is highly certain, although there is uncertainty about the timing of such deductibility. As a result, no liability for uncertain tax positions was recorded as of December 31, 2022 or 2021.

Fair Value Measurements

We measure certain of our assets and liabilities at fair value. Fair value represents the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. Fair value accounting requires characterization of the inputs used to measure fair value into a three-level fair value hierarchy as follows:

Level 1 — Inputs based on quoted prices in active markets for identical assets or liabilities. An active market is a market in which transactions occur with sufficient frequency and volume to provide pricing information on an ongoing basis.

Level 2 — Observable inputs that reflect the assumptions market participants would use in pricing the asset or liability developed based on market data obtained from sources independent from the entity.

Level 3 — Unobservable inputs that reflect the entity’s own assumptions about the assumptions market participants would use in pricing the asset or liability developed based on the best information available.

Eton Pharmaceuticals, Inc.

NOTES TO FINANCIAL STATEMENTS

(in thousands, except share and per share amounts)

Note 3 — Summary of Significant Accounting Policies (continued)

Fair value measurements are classified based on the lowest level of input that is significant to the measurement. The Company’s assessment of the significance of a particular input to the fair value measurement requires judgment, which may affect the valuation of the assets and liabilities and their placement within the fair value hierarchy levels. The determination of the fair values stated below takes into account the market for the Company’s financials, assets and liabilities, the associated credit risk and other factors as required. The Company considers active markets as those in which transactions for the assets or liabilities occur in sufficient frequency and volume to provide pricing information on an ongoing basis.

The Company’s financial instruments included cash and cash equivalents, accounts receivable, accounts payable, accrued liabilities and long-term debt obligation. The carrying amounts of these financial instruments, except for the long-term debt obligation, approximate their fair values due to the short-term maturities of these instruments. Based on borrowing rates currently available to the Company, the carrying value of the long-term debt obligation approximate their respective fair values.

Impact of New Accounting Pronouncements

There were no new accounting pronouncements issued by the Financial Accounting Standards Board (“FASB”) during the current period that would apply to the Company and have a material impact on its financial position or results of operations.

Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Current assets:
Cash and cash equivalents	$ 16,305	$ 14,406
Accounts receivable, net	1,852	5,471
Inventories	557	550
Prepaid expenses and other current assets	1,290	3,177
Total current assets	20,004	23,604
Property and equipment, net	72	115
Intangible assets, net	4,754	3,621
Operating lease right-of-use assets, net	188	104
Other long-term assets, net	12	21
Total assets	25,030	27,465
Current liabilities:
Accounts payable	1,766	1,774
Current portion of long-term debt	1,033	1,418
Accrued liabilities	3,662	1,366
Total current liabilities	6,461	4,558
Long-term debt, net of discount and including accrued fees	5,384	5,262
Operating lease liabilities, net of current portion	107	15
Total liabilities	11,952	9,835
Commitments and contingencies (Note 14)
Stockholders’ equity
Common stock, $0.001 par value; 50,000,000 shares authorized; 25,353,119 and 24,626,004 shares issued and outstanding at December 31, 2022 and 2021, respectively	25	25
Additional paid-in capital	116,187	111,718
Accumulated deficit	(103,134)	(94,113)
Total stockholders’ equity	13,078	17,630
Total liabilities and stockholders’ equity	$ 25,030	$ 27,465

Property and Equipment (Tables)

12 Months Ended

Dec. 31, 2022

Property, Plant and Equipment [Abstract]

Schedule of Property and Equipment

Property and equipment consist of the following:

Schedule of Property and Equipment

	December 31, 2022			December 31, 2021
Computer hardware and software	$	177		$	157
Furniture and fixtures		112			106
Equipment		52			132
Leasehold improvements		71			71
Construction in progress		12			—
Property and equipment, gross		424			466
Less: accumulated depreciation and amortization		(352	)		(351	)
Property and equipment, net	$	72		$	115

Debt (Tables)

12 Months Ended

Dec. 31, 2022

Debt Disclosure [Abstract]

Schedule of Future Payments of Long Term Debt

The table below reflects the future annual payments for the SWK loan principal and interest as of December 31, 2022.

	Amount
2023	$	1,853
2024		6,595
Total payments		8,448
Less: amount representing interest		(1,833	)
Loan payable, gross		6,615
Less: current portion of long-term debt		(1,033	)
Less: unamortized discount		(198	)
Long-term debt, net of unamortized discount	$	5,384

Leases

12 Months Ended

Dec. 31, 2022

Leases

Leases

Note 11 — Leases

The Company recognizes a right-of-use (“ROU”) asset and a lease liability on the balance sheet for substantially all leases, including operating leases, and separates lease components from non-lease components related to its office space lease.

On January 12, 2018, the Company signed an amended lease agreement to lease additional office space adjacent to its current corporate office space in Deer Park, Illinois. The amended lease was scheduled to expire at the end of March 2021. In October 2020, the Company renewed its office lease for a two-year period through March 31, 2023 and recorded $195 in ROU assets and $195 in operating lease liabilities in association with the lease extension. In November 2022, the Company renewed its office lease for a two-year period through March 31, 2025 and recorded $188 in ROU assets and $188 in operating lease liabilities in association with the lease extension. On March 7, 2018, the Company entered into a lease for laboratory space at a complex in Lake Zurich, Illinois. The lease commenced on March 7, 2018 and was scheduled to expire in February 2021. In November 2020, this laboratory lease was extended to June 2021 and was not extended after that date as the Company completed an evaluation its laboratory operations requirements and determined it would discontinue the laboratory activities and outsource its requirements.

The Company does not have any lease contracts that contain: (1) an option to extend that the Company is reasonably certain to exercise, (2) an option to terminate that the Company is reasonably certain to exercise, or (3) an option to extend (or not to terminate) in which exercise of the option is controlled by the lessor. Additionally, the Company does not have any leases with residual value guarantees or material restrictive covenants. Lease liabilities and their corresponding right-of-use assets have been recorded based on the present value of the future lease payments over the expected lease term. One of the Company’s lease agreements contains provisions for escalating rent payments over the term of the lease.

The Company’s leases do not contain readily determinable implicit discount rates, and therefore, the Company was required to use its incremental borrowing rate of 7.8% to discount the future lease payments based on information available at lease commencement. In October 2020, the new discount rate for the office lease extension was estimated at 5.4%. In November 2022, the new discount rate for an additional office lease extension was estimated at 8.6%. The incremental borrowing rate was estimated by determining the rate of interest that the Company would have to pay to borrow on a collateralized basis over a similar term an amount equal to the lease payments in a similar economic environment.

The Company’s operating lease cost as presented in the “Research and Development” and “General and Administrative” captions in the statements of operations was $0, $9 and $55 and $82, $86 and $84 for the years ended December 31, 2022, 2021 and 2020, respectively. For the years ended December 31, 2022, 2021, and 2020, the Company recorded $87, $113, and $139, respectively, in rent expense. Cash paid for amounts included in the measurement of operating lease liabilities was $88 and $83 for years ended December 31, 2022 and 2021, respectively. The ROU asset amortization for years ended December 31, 2022, 2021, and 2020 was $82, $88 and $129, respectively, and is reflected in depreciation and amortization in the Company’s statements of cash flows. As of December 31, 2022, the weighted-average remaining lease term was 2.25 years, and the weighted-average discount rate was 8.6%.

Eton Pharmaceuticals, Inc.

NOTES TO FINANCIAL STATEMENTS

(in thousands, except share and per share amounts)

Note 11 — Leases (continued)

The table below presents the lease-related assets and liabilities recorded on the balance sheet as of December 31, 2022:


Assets	Classification
Operating lease right-of-use assets	Operating lease right-of-use assets, net	$	188
Total leased assets		$	188
Liabilities
Operating lease liabilities, current	Accrued liabilities	$	75
Operating lease liabilities, noncurrent	Operating lease liabilities, net of current portion		107
Total operating lease liabilities		$	182

The Company’s future annual lease commitments as of December 31, 2022 are as indicated below:

Schedule of Future Lease Commitments

	Total			2023		2024		2025
Undiscounted lease payments	$	201		$	88	$	90	$	23
Less: Imputed interest		(19	)
Total lease liabilities	$	182

Share-Based Payment Awards (Details Narrative) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended		12 Months Ended
	Apr. 30, 2021	Apr. 30, 2020	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Jan. 02, 2022	Jan. 02, 2021	Jan. 02, 2020	Dec. 31, 2019	Jan. 02, 2019	Dec. 31, 2018	May 31, 2017
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Common stock, shares outstanding			25,353,119	24,626,004
Modification expense			$ 104
Stock-based compensation expense			4,218	$ 3,381	$ 2,576
Proceeds from stock option exercised			251	541	367
Employees contribution amount			172	154	117
Share-Based Payment Arrangement, Option [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Unrecognized compensation costs			$ 3,868
Weighted average period			2 years
Restricted Stock Units (RSUs) [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Unrecognized compensation costs			$ 858
Weighted average period			3 years 6 months
Stock-based compensation expense			$ 114
General and Administrative Expense [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Modification expense			244
Stock-based compensation expense			3,954	2,838	2,295
Research and Development Expense [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Stock-based compensation expense			$ 264	$ 543	$ 281
Common Stock [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Stock-based compensation, shares					15,190
Stock option exercises, shares			25,000	144,233	194,878
Stock Options [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Stock option intrinsic value			$ 31
Stock option exercises, shares			25,000
Proceeds from stock option exercised			$ 35
RSA To New Employee [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Stock-based compensation, shares		15,190
Restricted stock vested percentage	100.00%	25.00%
Product Consultant [Member] \| Common Stock [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Stock options expiration period			10 years
Number of stock options issued to purchase common stock			50,000
Stock options expiration period			5 years
Board of Directors [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Exercise price, minimum			$ 1.37
Exercise price, maximum			$ 8.61
Employee Stock Purchase Plan [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Number of shares available for issuance			560,296
Stock option exercises, shares			69,884	49,155
2017 Equity Incentive Plan [Member] \| Maximum [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, number of shares authorized												5,000,000
2018 Equity Incentive Plan [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Number of shares available for issuance			239,167
Share reserve increased						985,040	972,512	715,099		704,317
Common stock, shares outstanding				24,626,004	24,312,808				17,877,486		17,607,928
Stock option exercises, shares			25,000	144,233
2018 Equity Incentive Plan [Member] \| January 1, 2019 and Through January 1, 2028 [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Percentage for total number of shares outstanding			4.00%
2018 Employee Stock Purchase Plan [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Number of shares available for issuance											150,000
Stock-based compensation expense			$ 128	$ 73	$ 71
Share based compensation for initial shares reserve, description			The Company’s ESPP provides for an initial reserve of 150,000 shares and this reserve is automatically increased on January 1 of each year by the lesser of 1% of the outstanding common shares at December 31 of the preceding year or 150,000 shares, subject to reduction at the discretion of the Company’s board of directors
Description for deductions to purchase stock at price per share			The terms of the ESPP permit employees of the Company to use payroll deductions to purchase stock at a price per share that is at least the lesser of (1) 85% of the fair market value of a share of common stock on the first date of an offering or (2) 85% of the fair market value of a share of common stock on the date of purchase. After the initial offering period, subsequent twelve-month offering periods automatically commence over the term of the ESPP on the day that immediately follows the conclusion of the preceding offering, each consisting of two purchase periods approximately six months in duration ending on or around June 10 and December 10 each year, subject to a restart feature if the Company’s stock price drops at the end of a six-month period within the twelve-month offering period
Weighted average grant date fair value issued			$ 1.17	$ 2.50	$ 2.32
Employees contribution amount			$ 234	$ 205
Accrued liabilities for remaining employee contributions			$ 23	$ 22

Schedule of Deferred Tax Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Income Tax Disclosure [Abstract]
Net operating losses	$ 17,183	$ 15,871
Stock-based expenses	3,090	2,135
Accruals and other	1,359	542
Total deferred tax assets	21,632	18,548
Valuation allowance	(21,632)	(18,548)
Net deferred tax assets

Income Taxes (Details Narrative) - USD ($) $ in Thousands	12 Months Ended
Income Taxes (Details Narrative) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2017
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Percentage for valuation reserve against deferred tax assets	100.00%	100.00%
Deferred tax assets, gross	$ 21,632	$ 18,548
Operating loss carryforwards	$ 60,281		$ 5,652
Net operating loss carryforward expiration	expire in 2029
Minimum [Member] \| Ownership [Member]
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Equity ownership percentage	50.00%
After December 31, 2017 [Member]
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Operating loss carryforwards	$ 54,629

Summary of Significant Accounting Policies (Policies)

12 Months Ended

Dec. 31, 2022

Accounting Policies [Abstract]

Basis of Presentation

Basis of Presentation

The Company has prepared the accompanying financial statements in accordance with GAAP.

Eton Pharmaceuticals, Inc.

NOTES TO FINANCIAL STATEMENTS

(in thousands, except share and per share amounts)

Note 3 — Summary of Significant Accounting Policies (continued)

Use of Estimates

Use of Estimates

Segment Information

Segment Information

Cash and Cash Equivalents

Cash and Cash Equivalents

Accounts Receivable

Accounts Receivable

Inventories

Inventories

Property and Equipment

Property and Equipment

Maintenance and repairs are charged to expense as incurred, while renewals and improvements are capitalized.

Eton Pharmaceuticals, Inc.

NOTES TO FINANCIAL STATEMENTS

(in thousands, except share and per share amounts)

Note 3 — Summary of Significant Accounting Policies (continued)

Intangible Assets

Intangible Assets


Year	Amortization Expense
2023	$	725
2024		725
2025		725
2026		725
2027		608
Thereafter		1,246
Total estimated amortization expense	$	4,754

Impairment of Long-Lived Assets

Impairment of Long-Lived Assets

Debt Issuance Costs and Debt Discount and Detachable Debt-Related Warrants

Debt Issuance Costs and Debt Discount and Detachable Debt-Related Warrants

Eton Pharmaceuticals, Inc.

NOTES TO FINANCIAL STATEMENTS

(in thousands, except share and per share amounts)

Note 3 — Summary of Significant Accounting Policies (continued)

Leases

Leases

Patent Costs

Patent Costs

Concentrations of Credit Risk, Sources of Supply and Significant Customers

Concentrations of Credit Risk, Sources of Supply and Significant Customers

Eton Pharmaceuticals, Inc.

NOTES TO FINANCIAL STATEMENTS

(in thousands, except share and per share amounts)

Note 3 — Summary of Significant Accounting Policies (continued)

Revenue Recognition for Contracts with Customers

Revenue Recognition for Contracts with Customers

Eton Pharmaceuticals, Inc.

NOTES TO FINANCIAL STATEMENTS

(in thousands, except share and per share amounts)

Note 3 — Summary of Significant Accounting Policies (continued)

Eton Pharmaceuticals, Inc.

NOTES TO FINANCIAL STATEMENTS

(in thousands, except share and per share amounts)

Note 3 — Summary of Significant Accounting Policies (continued)

Cost of Product Sales

Cost of Product Sales

Research and Development Expenses

Research and Development Expenses

Income (Loss) Per Share

Income (Loss) Per Share

Stock-Based Compensation

Stock-Based Compensation

Eton Pharmaceuticals, Inc.

NOTES TO FINANCIAL STATEMENTS

(in thousands, except share and per share amounts)

Note 3 — Summary of Significant Accounting Policies (continued)

Income Taxes

Income Taxes

Fair Value Measurements

Fair Value Measurements

Eton Pharmaceuticals, Inc.

NOTES TO FINANCIAL STATEMENTS

(in thousands, except share and per share amounts)

Note 3 — Summary of Significant Accounting Policies (continued)

Impact of New Accounting Pronouncements

Impact of New Accounting Pronouncements

Summary of Warrants Outstanding (Details) - $ / shares	Dec. 31, 2022	Jun. 26, 2022	Dec. 31, 2021
No. of Shares	483,380	467,242	1,554,826
Exercise Price	$ 7.29	$ 3.00
Placement Agent Warrants - IPO [Member]
No. of Shares	414,000
Exercise Price	$ 7.50
SWK Warrants – Debt (Tranche #1) [Member]
No. of Shares	51,239
Exercise Price	$ 5.86
SWK Warrants – Debt (Tranche #2) [Member]
No. of Shares	18,141
Exercise Price	$ 6.62

Schedule of Provision for Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Current:
Federal
State
Total current expense
Deferred:
Federal	2,272	460	6,020
State	812	185	2,151
Change in valuation allowance	(3,084)	(645)	(8,171)
Total deferred expense
Total provision

Related-Party Transactions

12 Months Ended

Dec. 31, 2022

Related-Party Transactions

Note 10 — Related-Party Transactions

Harrow

The Chief Executive Officer of Harrow Health, Inc. (“Harrow”) was a member of the Company’s board of directors until March 17, 2021 when he retired from service with the board. The Company issued 25,000 shares to the Harrow CEO in April 2021 after his retirement from the Company’s board associated with RSUs that were previously fully vested. As of December 31, 2022, Harrow owned 1,982,000 shares of Eton’s common shares which represents 7.8% of the Company’s common shares outstanding.

In March 2021, the Company closed its laboratory operation in Lake Zurich, Illinois and in May 2021 it reached an agreement for Imprimis Pharmaceuticals, a subsidiary of Harrow, to purchase its lab equipment for $700 which was $181 above the Company’s net book value of the equipment.

Chief Executive Officer

The CEO has a partial interest in a company that the Company has partnered with for its EM-100/Alaway Preservative Free eye allergy product as described below.

The Company acquired the exclusive rights to sell the EM-100 product in the United States pursuant to a sales and marketing agreement (the “Eyemax Agreement”) dated August 11, 2017 between the Company and Eyemax LLC (“Eyemax”), an entity affiliated with the Company’s CEO. The Company also held a right of first refusal to obtain the exclusive license rights for geographic areas outside of the United States. Pursuant to the Eyemax Agreement, the Company was responsible for all costs of testing and FDA approval of the product, other than the FDA filing fee which was paid by Eyemax. The Company was also to be responsible for commercializing the product in the United States at its expense. The Company paid Eyemax $250 upon execution of the Eyemax Agreement, which was recorded as a component of R&D expense. Under the terms of the original agreement, the Company would pay Eyemax $250 upon FDA approval and $500 upon the first commercial sale of the product and pay Eyemax a royalty of 10% on the net sales of all products. The Eyemax Agreement was for an initial term of 10 years from the date of the Eyemax Agreement, subject to successive two-year renewals unless the Company elected to terminate the Eyemax Agreement.

On February 18, 2019, the Company entered into an Amended and Restated Agreement with Eyemax amending the Sales Agreement (the “Amended Agreement”). Pursuant to the Amended Agreement, Eyemax sold the Company all of its right, title and interest in EM-100, including any such product that incorporates or utilizes Eyemax’s intellectual property rights. Under the Amended Agreement, the Company assumed certain liabilities of Eyemax under its Exclusive Development & Supply Agreement with Excelvision SAS dated as of July 11, 2013, as amended (the “Excelvision Agreement”), with respect to certain territories and arising during certain time periods. Pursuant to the Amended Agreement, the Company paid Eyemax two milestone payments: (i) one milestone payment for $250 upon regulatory approval in the territory by the FDA of the first single agent product and (ii) one milestone payment for $500 following the first commercial sale of the first single agent product in the territory. Following payment of the milestones, the Company is entitled to retain all of the non-royalty transaction revenues and royalties up to $2,000 (the “Recovery Amount”). After the Company has retained the full Recovery Amount, it is entitled to retain half of all royalty and non-royalty transaction revenue. The Company has realized $1,818 of the non-royalty and royalty revenue as of December 31, 2022. The Amended Agreement also contains customary representations, warranties, covenants and indemnities by the parties. The EM-100 asset and its associated product rights were sold to Bausch Health on February 18, 2019 and future potential royalties of twelve percent on Bausch Health sales of the product, named Alaway® Preservative Free by Bausch, which was approved by the FDA in September 2020, will be split between Eyemax and the Company. The royalty from Bausch Health is subject to reduction if a competitive product with the same active pharmaceutical ingredient is launched in the U.S. or if the product’s U.S market share falls below a specified target percentage.

There were no amounts due to Eyemax under the terms of the Amended Agreement as of December 31, 2022 or December 31, 2021.

Share-Based Payment Awards

12 Months Ended

Dec. 31, 2022

Share-Based Payment Arrangement [Abstract]

Share-Based Payment Awards

Note 8 — Share-Based Payment Awards

The Company’s board of directors and stockholders approved the Eton Pharmaceuticals, Inc. 2017 Equity Incentive Plan in May 2017 (the “2017 Plan”), which authorized the issuance of up to 5,000,000 shares of the Company’s common stock. In conjunction with the Company’s IPO in November 2018, the Company’s stockholders and board of directors approved the 2018 Equity Incentive Plan, as amended (the “2018 Plan”) which succeeded the 2017 Plan. The Company has granted RSAs, stock options and RSUs for its common stock under the 2017 Plan and 2018 Plan as detailed in the tables below. There were 239,167 shares available for future issuance under the 2018 Plan as of December 31, 2022.

Eton Pharmaceuticals, Inc.

NOTES TO FINANCIAL STATEMENTS

(in thousands, except share and per share amounts)

Note 8 — Share-Based Payment Awards (continued)

Shares that are expired, terminated, surrendered or canceled without having been fully exercised will be available for future awards under the 2018 Plan. In addition, the 2018 Plan provides that commencing January 1, 2019 and through January 1, 2028, the share reserve will be increased by 4% of the total number of shares outstanding as of the preceding December 31, subject to a reduction at the discretion of the Company’s board of directors. On January 1, 2019, the share reserve was increased by 704,317 shares based on the 17,607,928 shares of common stock outstanding at December 31, 2018. On January 1, 2020, the share reserve was increased by 715,099 shares based on the 17,877,486 shares of common stock outstanding at December 31, 2019. On January 1, 2021, the share reserve was increased by 972,512 shares based on the 24,312,808 shares of common stock outstanding at December 31, 2020. On January 1, 2022, the share reserve was increased by 985,040 shares based on the 24,626,004 shares of common stock outstanding at December 31, 2021. The exercise price for stock options granted is not less than the fair value of common stock as determined by the board of directors as of the date of grant. The Company uses the closing stock price on the date of grant as the exercise price.

In April 2020, the Company issued 15,190 shares of its common stock as an RSA to a new employee. This RSA vested 25% every three months and was 100% vested in April 2021.

To date, all stock options issued have been non-qualified stock options, and the exercise prices were set at the fair value for the shares at the dates of grant. Options typically have a ten-year life, except for options to purchase 50,000 shares of the Company’s common stock granted to product consultants in July 2017 that expired, unexercised, in July 2022 as the Company was not able to file certain product submissions to the FDA prior to the five-year expiration date. Furthermore, these option awards to the Company’s product consultants would not vest unless certain product submissions are made to the FDA, and accordingly, the Company has not recorded any expense for these contingently vesting option awards to its product consultants.

In July 2022 and September 2022, the Company’s board of directors approved modifications of certain outstanding awards of two senior executives, one of whom retired in May 2022 and the other whose employment was terminated in July 2022. The combined awards had an exercise price range of $1.37 to $8.61 which were set to expire 90 days after retirement or termination as the case may be, and the Company extended the expiration dates to April 2023. No other terms were modified. Due to these modifications, the Company incurred a modification expense of approximately $104 that is included in general and administration expense on the Statement of Operations for the year ended December 31, 2022.

For the years ended December 31, 2022, 2021, and 2020, the Company’s total stock-based compensation expense was $4,218, $3,381 and $2,576, respectively. Of these amounts, $3,954, $2,838 and $2,295 was recorded in general and administrative expenses, respectively, and $264, $543 and $281 was recorded in R&D expenses, respectively.

Stock Options

The following table summarizes stock option activity during the year ended December 31, 2022:

Summary of Stock Option Activity

	Shares			Weighted Average Exercise Price		Weighted Average Remaining Contractual Term		Aggregate Intrinsic Value
Options outstanding as of January 1, 2022		3,513,719		$	5.22
Issued		1,333,770			3.72
Exercised		(25,000	)		1.38
Forfeited/Cancelled		(420,197	)		6.04
Options outstanding as of December 31, 2022		4,402,292		$	4.71		7.5	$	884
Options exercisable at December 31, 2022		3,037,846		$	4.68		7.0	$	800
Options vested and expected to vest at December 31, 2022		4,352,292		$	4.74		7.5	$	812

The aggregate intrinsic value of stock options is calculated as the difference between the exercise price of the stock options and the fair value of the Company’s common stock for those stock options that had strike prices lower than the fair value of the Company’s common stock at December 31. The intrinsic value of the options exercised during 2022 was $31.

Eton Pharmaceuticals, Inc.

NOTES TO FINANCIAL STATEMENTS

(in thousands, except share and per share amounts)

Note 8 — Share-Based Payment Awards (continued)

There were 25,000 shares issued for exercise of stock options during the year ended December 31, 2022 for proceeds of $35.

The assumptions used to calculate the fair value of options granted during the years ended December 31, , 2022, 2021, and 2020 under the BSM were as follows:

	December 31, 2022			December 31, 2021			December 31, 2020
Expected dividends		—	%		—	%		—	%
Expected volatility		70	%		70-80	%		95	%
Risk-free interest rate		1.5-3.9 %			0.9-1.4	%		0.4-0.7	%
Expected term		5.9 years			6.0 years			5.9 years
Weighted average fair value	$	2.32		$	5.64		$	3.06

Expected Term — The Company has opted to use the “simplified method” for estimating the expected term of options granted to employees and directors, whereby the expected term equals the arithmetic average of the vesting term and the original contractual term of the option (generally 10 years). The expected term of options granted to non-employees equals the contractual life of the options.

Expected Volatility — Due to the Company’s limited operating history and a lack of Company-specific historical and implied volatility data, the Company has based its estimate of expected volatility on the historical volatility of a group of similar companies that are publicly traded. The historical volatility data was computed using the daily closing prices for the selected companies’ shares during the equivalent period of the calculated expected term of the stock-based awards. The Company has also applied some limited weighting to its own volatility.

Risk-Free Interest Rate — The risk-free rate assumption is based on the U.S. Treasury instruments with maturities similar to the expected term of the Company’s stock options.

Expected Dividend — The Company has not issued any dividends in its history and does not expect to issue dividends over the life of the options and therefore has estimated the dividend yield to be zero.

Fair value of Common Stock —The Company uses the closing stock price on the date of grant for the fair value of the common stock.

As of December 31, 2022, there was a total of $3,868 of unrecognized compensation costs related to non-vested stock option awards which will be recognized over a weighted average period of 2 years.

Restricted Stock Units (RSUs)

The following table summarizes restricted stock unit activity during the year ended December 31, 2022:

	Number of Units			Weighted Average Grant-Date Fair Value Per Unit
Outstanding and unvested as of January 1, 2022		—		$	—
Granted		373,606		$	2.63
Vested		—			—
Forfeited		(4,000	)	$	2.63
Outstanding and unvested as of December 31, 2022		369,606		$	$2.63

Stock-based compensation related to RSUs was $114 for the year ended December 31, 2022. As of December 31, 2022, there was $858 of unrecognized stock-based compensation expense related to unvested RSUs which will be recognized over a weighted average period of 3.5 years.

Eton Pharmaceuticals, Inc.

NOTES TO FINANCIAL STATEMENTS

(in thousands, except share and per share amounts)

Note 8 — Share-Based Payment Awards (continued)

Employee Stock Purchase Plan

In December 2018, the Company’s board of directors adopted an initial offering of the Company’s common stock under the Company’s ESPP. The Company’s ESPP provides for an initial reserve of 150,000 shares and this reserve is automatically increased on January 1 of each year by the lesser of 1% of the outstanding common shares at December 31 of the preceding year or 150,000 shares, subject to reduction at the discretion of the Company’s board of directors.

The terms of the ESPP permit employees of the Company to use payroll deductions to purchase stock at a price per share that is at least the lesser of (1) 85% of the fair market value of a share of common stock on the first date of an offering or (2) 85% of the fair market value of a share of common stock on the date of purchase. After the initial offering period, subsequent twelve-month offering periods automatically commence over the term of the ESPP on the day that immediately follows the conclusion of the preceding offering, each consisting of two purchase periods approximately six months in duration ending on or around June 10 and December 10 each year, subject to a restart feature if the Company’s stock price drops at the end of a six-month period within the twelve-month offering period.

The Company recorded an expense of $128, $73 and $71 in 2022, 2021, and 2020, respectively, related to the ESPP. For the years ended December 31, 2022 and 2021, there were 69,884 and 49,155 share issuances, respectively, under the ESPP. The weighted average grant date fair value of share awards in 2022, 2021, and 2020 was $1.17, $2.50 and $2.32 per share, respectively. Employees contributed $234 and $205 to the ESPP during 2022 and 2021, respectively. Of these amounts, $23 and $22 at December 31, 2022 and 2021, respectively, are included in accrued liabilities in the accompanying balance sheets. As of December 31, 2022, there were 560,296 shares available for issuance under the ESPP.

Share-Based Payment Awards (Tables)

12 Months Ended

Dec. 31, 2022

Share-Based Payment Arrangement [Abstract]

Summary of Stock Option Activity

The following table summarizes stock option activity during the year ended December 31, 2022:

Summary of Stock Option Activity

	Shares			Weighted Average Exercise Price		Weighted Average Remaining Contractual Term		Aggregate Intrinsic Value
Options outstanding as of January 1, 2022		3,513,719		$	5.22
Issued		1,333,770			3.72
Exercised		(25,000	)		1.38
Forfeited/Cancelled		(420,197	)		6.04
Options outstanding as of December 31, 2022		4,402,292		$	4.71		7.5	$	884
Options exercisable at December 31, 2022		3,037,846		$	4.68		7.0	$	800
Options vested and expected to vest at December 31, 2022		4,352,292		$	4.74		7.5	$	812

Schedule of Assumptions Used to Calculate Fair Value of Options Granted

The assumptions used to calculate the fair value of options granted during the years ended December 31, , 2022, 2021, and 2020 under the BSM were as follows:

	December 31, 2022			December 31, 2021			December 31, 2020
Expected dividends		—	%		—	%		—	%
Expected volatility		70	%		70-80	%		95	%
Risk-free interest rate		1.5-3.9 %			0.9-1.4	%		0.4-0.7	%
Expected term		5.9 years			6.0 years			5.9 years
Weighted average fair value	$	2.32		$	5.64		$	3.06

Summary of Activity for Restricted Stock Awards

The following table summarizes restricted stock unit activity during the year ended December 31, 2022:

	Number of Units			Weighted Average Grant-Date Fair Value Per Unit
Outstanding and unvested as of January 1, 2022		—		$	—
Granted		373,606		$	2.63
Vested		—			—
Forfeited		(4,000	)	$	2.63
Outstanding and unvested as of December 31, 2022		369,606		$	$2.63

Schedule of Intangible Assets Amortization Expenses (Details) $ in Thousands	Dec. 31, 2022 USD ($)
Accounting Policies [Abstract]
2023	$ 725
2024	725
2025	725
2026	725
2027	608
Thereafter	1,246
Total estimated amortization expense	$ 4,754

Property and Equipment (Details Narrative) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Property, Plant and Equipment [Abstract]
Depreciation and amortization expense	$ 66	$ 155	$ 347

Common Stock

12 Months Ended

Dec. 31, 2022

Equity [Abstract]

Common Stock

Note 6 — Common Stock

The Company has 50,000,000 authorized shares of $0.001 par value common stock as per its Amended and Restated Certificate of Incorporation.

In March and April 2020, the Company entered into securities purchase agreements with various investors and sold an aggregate of 2,600,000 shares of its common stock at a price of $3.00 per share and received $7,756 in net proceeds after deducting issuance costs associated with the sale.

In March 2020, the Company issued 379,474 shares of its common stock to Diurnal Limited (“Diurnal”) as a milestone fee for acquiring the U.S. marketing rights to ALKINDI SPRINKLE®, an orphan drug product currently under review with the FDA (see Note 14). The shares were valued at $1,264 based on the Company’s closing stock price on the date of issuance and this amount was recorded as a component of the Company’s research and development expense and a corresponding increase to its additional paid-in-capital.

In October 2020, the Company issued 3,220,000 shares of its common stock in a public offering at an offering price of $7.00 per share and received net proceeds of $21,026.

Eton Pharmaceuticals, Inc.

NOTES TO FINANCIAL STATEMENTS

(in thousands, except share and per share amounts)

Note 6 — Common Stock (continued)

For the years ended December 31, 2022 and 2021, the Company issued 25,000 and 144,233 shares, respectively, of its common stock resulting from stock option exercises under its 2018 Equity Incentive Plan (see Note 8). For the years ended December 31, 2022 and 2021, the Company issued 69,884 and 49,155 shares, respectively, under the Company’s Employee Stock Purchase Plan (“ESPP”). In April 2020, the Company issued 15,190 shares of its common stock as an RSA to a new employee. This RSA vested 25% every three months and was 100% vested in April 2021. In April 2021, the Company issued 25,000 shares of its common stock to a member of its board of directors upon his retirement from the board in connection with previously vested RSUs. During 2022, there were 1,067,242 warrants exercised, a portion of which was a cashless exercise, resulting in 632,231 shares of common stock being issued by the Company.

- Definition

The entire disclosure for shareholders' equity comprised of portions attributable to the parent entity and noncontrolling interest, including other comprehensive income. Includes, but is not limited to, balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings, accumulated balance for each classification of other comprehensive income and amount of comprehensive income.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-URI https://asc.fasb.org/topic&trid=2208762

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 13
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=126973232&loc=SL123496158-112644

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 13
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+ Details

Summary of Rollforward of The Warrants Outstanding (Details)	12 Months Ended
	Dec. 31, 2022 shares
Common Stock Warrants
Balance as of the beginning of the year	1,554,826
Exercise of Placement Agent Warrants - 2017 Preferred Stock Offering	(1,067,242)
Exercise of Placement Agent Warrants - 2017 Preferred Stock Offering	(4,204)
Balance as of the end of the year	483,380

Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2022

Accounting Policies [Abstract]

Schedule of Intangible Assets Amortization Expenses


Year	Amortization Expense
2023	$	725
2024		725
2025		725
2026		725
2027		608
Thereafter		1,246
Total estimated amortization expense	$	4,754

Basic and Diluted Net Loss per Common Share (Details Narrative) - shares	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Earnings Per Share [Abstract]
Anti-dilutive securities excluded from calculation of diluted net loss per share	5,494,153	4,286,687	3,371,489

Summary of Significant Accounting Policies (Details Narrative)	1 Months Ended		3 Months Ended	12 Months Ended
	Sep. 30, 2022 USD ($)	Nov. 30, 2021 USD ($)	Mar. 31, 2022 USD ($)	Dec. 31, 2022 USD ($) Segment	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Jun. 30, 2022 USD ($)
Product Information [Line Items]
Number of reportable segments \| Segment				1
Allowances for doubtful accounts				$ 262,000	$ 96,000
Inventory write-down				62,000	1,414,000
Payments to acquire intangible assets				2,750,000	3,250,000
Accumulated amortization				1,996,000
Amortization of intangible assets				1,617,000	204,000	$ 150,000
Finance lease				$ 0	$ 0
Percentage for valuation reserve against deferred tax assets				100.00%	100.00%
Revenue Benchmark [Member] \| Customer Concentration Risk [Member] \| Customers [Member]
Product Information [Line Items]
Concentration risk, percentage				45.50%	9.00%
Accounts Receivable [Member] \| Customer Concentration Risk [Member] \| Customers [Member]
Product Information [Line Items]
Concentration risk, percentage				79.80%	6.40%
Betaine Anhydrous Product [Member]
Product Information [Line Items]
Payments to acquire intangible assets	$ 2,000,000
Finite-lived intangible asset, useful life	5 years
Carglumic Acid Product Rights [Member]
Product Information [Line Items]
Payments to acquire intangible assets		$ 3,250,000
Finite-lived intangible asset, useful life		10 years
Biorphen Product [Member]
Product Information [Line Items]
Payments to acquire intangible assets							$ 750,000
Finite-lived intangible asset, useful life							5 years
Biorphen [Member]
Product Information [Line Items]
Accumulated amortization				$ 75,000				$ 275,000
Rezipres Product [Member]
Product Information [Line Items]
Payments to acquire intangible assets			$ 750,000
Finite-lived intangible asset, useful life			5 years
Dr Reddys [Member]
Product Information [Line Items]
Accumulated amortization								$ 738,000
Computer Equipment [Member]
Product Information [Line Items]
Estimated useful lives for property and equipment				3 years
Furniture and Fixtures [Member]
Product Information [Line Items]
Estimated useful lives for property and equipment				5 years

Debt

12 Months Ended

Dec. 31, 2022

Debt Disclosure [Abstract]

Debt

Note 5 – Debt

SWK Loan

On November 13, 2019, the Company entered into a credit agreement (the “SWK Credit Agreement”) with SWK Holdings Corporation (“SWK”) which provided for up to $10,000 in financing. The Company received proceeds of $5,000 at closing and was able to borrow an additional $5,000 upon the FDA approval of a second product developed by the Company, excluding EM-100. In March 2020, in conjunction with the Company’s ALKINDI SPRINKLE® product licensing agreement (see Note 14) and the Company’s March 2020 sale of shares of its common stock (see Note 6), the Company and SWK amended the SWK Credit Agreement. The amendment provided the Company with the option to immediately draw $2,000 and the ability to borrow an additional $3,000 based upon the FDA approval of EM-100 and ALKINDI SPRINKLE® which subsequently occurred in September 2020. Accordingly, the Company borrowed an additional $2,000 on August 11, 2020. The term of the SWK Credit Agreement is for five years and borrowings bear interest at a rate of LIBOR 3-month plus 10.0%, subject to a stated LIBOR floor rate of 2.0%. A 2.0% unused credit limit fee is assessed during the first twelve months after the date of the SWK Credit Agreement and loan fees include a 5.0% exit fee based on the principal amounts drawn which is payable at the end of the term of the SWK Credit Agreement. The Company was required to maintain a minimum cash balance of $3,000, only pay interest on the debt until February 2022 and then pay 5.5% of the loan principal balance commencing on February 15, 2022 and then every three months thereafter until November 13, 2024 at which time the remaining principal balance is due. Borrowings under the SWK Credit Agreement are secured by the Company’s assets. The SWK Credit Agreement contains customary default provisions and covenants which include limits on additional indebtedness. In March 2020, SWK provided a waiver for the Company to obtain loans with the Small Business Association. In February 2021, the Company notified SWK that it will not require additional borrowing capacity under the SWK Credit Agreement and terminated the additional borrowing capacity with SWK.

In connection with the initial $5,000 borrowed in November 2019, the Company issued warrants to SWK to purchase 51,239 shares of the Company’s common stock with an exercise price of $5.86 per share. The relative fair value of these 51,239 warrants was $226 and was estimated using the Black-Scholes-Merton option pricing model with the following assumptions: fair value of the Company’s common stock at issuance of $5.75 per share; seven-year contractual term; 95% volatility; 0% dividend rate; and a risk-free interest rate of 1.8%.

In connection with the additional $2,000 borrowed in August 2020, the Company issued warrants for 18,141 shares of its common stock at an exercise price of $6.62 per share. The relative fair value of the 18,141 warrants was $94 and was estimated using the Black-Scholes-Merton option pricing model with the following assumptions: fair value of the Company’s common stock at issuance of $6.85 per share; seven-year contractual term; 95% volatility; 0% dividend rate; and a risk-free interest rate of 0.4%.

These warrants (the “SWK Warrants”) are exercisable immediately and have a term of seven years from the date of issuance. The SWK Warrants are subject to a cashless exercise feature, with the exercise price and number of shares issuable upon exercise subject to change in connection with stock splits, dividends, reclassifications and other conditions.

On April 5, 2022, the Company and SWK entered into an amendment to the SWK Credit Agreement which allowed for a deferral of loan principal payments until May 2023 and reduced the interest rate to LIBOR 3-month plus 8.0%, subject to a stated LIBOR floor rate of 2.0%. In accordance with the change, the Company has classified $1,033 as principal due in the next 12 months and the remainder classified as long-term debt in its balance sheet at December 31, 2022. Because LIBOR was intended to be phased out by the end of 2021, future borrowings under our Credit Agreement could be subject to reference rates other than LIBOR. However, the cessation date of LIBOR has been deferred to June 30, 2023 and we do not expect the planned discontinuation of LIBOR to have a material impact on interest payments incurred under the SWK Credit Agreement. The Company is in discussions with SWK regarding an alternate reference rate.

The Company recorded interest expense of $955, $1,042 and $884 in 2022, 2021 and 2020, respectively, which included $127, $148 and $121, respectively, of debt discount amortization. The Company had accrued interest of $231 and $134 as of December 31, 2022 and 2021, respectively, which is included in accrued liabilities in the accompanying balance sheets.

Eton Pharmaceuticals, Inc.

NOTES TO FINANCIAL STATEMENTS

(in thousands, except share and per share amounts)

Note 5 – Debt (continued)

The table below reflects the future annual payments for the SWK loan principal and interest as of December 31, 2022.

	Amount
2023	$	1,853
2024		6,595
Total payments		8,448
Less: amount representing interest		(1,833	)
Loan payable, gross		6,615
Less: current portion of long-term debt		(1,033	)
Less: unamortized discount		(198	)
Long-term debt, net of unamortized discount	$	5,384

PPP loan

On May 4, 2020, the Company received $361 in loan proceeds under the Paycheck Protection Program (“PPP”) from the Small Business Administration (“SBA”) through its banking relationship with Bank of America. On May 20, 2021, the Company received notice that the loan principal and cumulative interest of $4 was forgiven in full as permitted under the applicable SBA guidelines for PPP loans. The $365 gain on debt extinguishment is reflected in non-operating income for the year ended December 31, 2021.

EIDL loan

On July 21, 2020, the Company received $150 in loan proceeds under the Economic Injury Disaster Loan program (“EIDL”) from the SBA. The Company paid off the full EIDL loan principal and its cumulative interest of $6 in July 2021.

Leases (Tables)

12 Months Ended

Dec. 31, 2022

Leases

Schedule of Lease-related Assets and Liabilities

The table below presents the lease-related assets and liabilities recorded on the balance sheet as of December 31, 2022:


Assets	Classification
Operating lease right-of-use assets	Operating lease right-of-use assets, net	$	188
Total leased assets		$	188
Liabilities
Operating lease liabilities, current	Accrued liabilities	$	75
Operating lease liabilities, noncurrent	Operating lease liabilities, net of current portion		107
Total operating lease liabilities		$	182

Schedule of Future Lease Commitments

The Company’s future annual lease commitments as of December 31, 2022 are as indicated below:

Schedule of Future Lease Commitments

	Total			2023		2024		2025
Undiscounted lease payments	$	201		$	88	$	90	$	23
Less: Imputed interest		(19	)
Total lease liabilities	$	182

Liquidity Considerations (Details Narrative) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Accumulated deficit	$ 103,134	$ 94,113
Net loss	9,021	1,955	$ 27,970
Cash and cash equivalents	$ 16,305	$ 14,406

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

+ Details

Income Taxes

12 Months Ended

Dec. 31, 2022

Income Tax Disclosure [Abstract]

Income Taxes

Note 12 – Income Taxes

The provision for income taxes for the Company consists of the following for the years ended December 31, 2022, 2021 and 2020:

Schedule of Provision for Income Taxes

	Year ended			Year ended			Year ended
	December 31,			December 31,			December 31,
	2022			2021			2020
Current:
Federal	$	—		$	—		$	—
State		—			—			—
Total current expense		—			—			—

Deferred:
Federal		2,272			460			6,020
State		812			185			2,151
Change in valuation allowance		(3,084	)		(645	)		(8,171	)
Total deferred expense		—			—			—
Total provision	$	—		$	—		$	—

Deferred income taxes reflect the net tax effects of temporary differences between the carrying amounts of assets and liabilities for financial reporting purposes and the amounts used for income tax purposes.

Eton Pharmaceuticals, Inc.

NOTES TO FINANCIAL STATEMENTS

(in thousands, except share and per share amounts)

Note 12 – Income Taxes (continued)

The significant components of the Company’s deferred tax assets as of December 31, 2022 and 2021 are as follows:

Schedule of Deferred Tax Assets

	December 31,			December 31,
	2022			2021
Net operating losses	$	17,183		$	15,871
Stock-based expenses		3,090			2,135
Accruals and other		1,359			542
Total deferred tax assets		21,632			18,548
Valuation allowance		(21,632	)		(18,548	)
Net deferred tax assets	$	—		$	—

Based on the uncertainty of future taxable income at this time management believes a 100% valuation reserve for the $21,632 and $18,548 deferred tax assets at December 31, 2022 and 2021, respectively, is appropriate.

A reconciliation of the statutory federal tax rate to effective tax rate is shown below:

	Year ended December 31			Year ended December 31,			Year ended December 31,
	2022			2021			2020
Benefit at statutory rate		(21.0	)%		(21.0	)%		(21.0	)%
Permanent items (primarily warrants and stock compensation)		(3.3	)		(2.5	)		(0.5	)
State tax benefit		(8.7	)		(9.5	)		(7.7	)
Federal rate change		—			—			—
Other items		—			—			—
Increase in valuation allowance		33.0			33.0			29.2
Income tax expense		—	%		—	%		—	%

The Company has a federal and state NOL carryforward of $60,281 as of December 31, 2022. Under the Tax Act, federal NOLs incurred in taxable years ending after December 31, 2017 in the amount of $54,629 may be carried forward indefinitely and are subject to an 80% usage limitation. The deductibility of federal NOLs generated in tax years beginning before December 31, 2017 in the amount of $5,652 will expire in 2037. The state NOL carry forward will begin to expire in 2029.

In addition, under Sections 382 and 383 of the Internal Revenue Code of 1986, as amended, and corresponding provisions of state law, if a corporation undergoes an “ownership change,” which is generally defined as a greater than 50% change (by value) in its equity ownership over a three-year period, the corporation’s ability to use its pre-change NOL carryforwards and other pre-change tax attributes (such as research tax credits) to offset its post-change income may be limited.

- Definition

The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 21
-URI https://asc.fasb.org/extlink&oid=121826272&loc=d3e32857-109319

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
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-Section S99
-Paragraph 2
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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-Paragraph 17
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
-Topic 740
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-Section S99
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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-Subparagraph (SX 210.4-08(h)(2))
-URI https://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

+ Details

Income Taxes (Tables)

12 Months Ended

Dec. 31, 2022

Income Tax Disclosure [Abstract]

Schedule of Provision for Income Taxes

The provision for income taxes for the Company consists of the following for the years ended December 31, 2022, 2021 and 2020:

Schedule of Provision for Income Taxes

	Year ended			Year ended			Year ended
	December 31,			December 31,			December 31,
	2022			2021			2020
Current:
Federal	$	—		$	—		$	—
State		—			—			—
Total current expense		—			—			—

Deferred:
Federal		2,272			460			6,020
State		812			185			2,151
Change in valuation allowance		(3,084	)		(645	)		(8,171	)
Total deferred expense		—			—			—
Total provision	$	—		$	—		$	—

Schedule of Deferred Tax Assets

The significant components of the Company’s deferred tax assets as of December 31, 2022 and 2021 are as follows:

Schedule of Deferred Tax Assets

	December 31,			December 31,
	2022			2021
Net operating losses	$	17,183		$	15,871
Stock-based expenses		3,090			2,135
Accruals and other		1,359			542
Total deferred tax assets		21,632			18,548
Valuation allowance		(21,632	)		(18,548	)
Net deferred tax assets	$	—		$	—

Schedule of Reconciliation of Statutory Federal Tax Rate

A reconciliation of the statutory federal tax rate to effective tax rate is shown below:

	Year ended December 31			Year ended December 31,			Year ended December 31,
	2022			2021			2020
Benefit at statutory rate		(21.0	)%		(21.0	)%		(21.0	)%
Permanent items (primarily warrants and stock compensation)		(3.3	)		(2.5	)		(0.5	)
State tax benefit		(8.7	)		(9.5	)		(7.7	)
Federal rate change		—			—			—
Other items		—			—			—
Increase in valuation allowance		33.0			33.0			29.2
Income tax expense		—	%		—	%		—	%

Statements of Stockholders' Equity - USD ($) $ in Thousands	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Total
Beginning balance, value at Dec. 31, 2019	$ 18	$ 74,720	$ (64,188)	$ 10,550
Beginning balance, shares at Dec. 31, 2019	17,877,486
Stock-based compensation		2,576		2,576
Stock-based compensation, shares	15,190
Stock option exercises		255		255
Stock option exercises, shares	194,878
Employee stock purchase plan		112		112
Employee stock purchase plan, shares	25,780
Proceeds from sales of common stock, net of offering costs	$ 6	28,776		28,782
Proceeds from sales of common stock, net of offering costs, shares	5,820,000
Issuance of common stock for product candidate licensing rights		1,264		1,264
Issuance of common stock for product candidate licensing rights, shares	379,474
Relative fair value of warrants to purchase common stock issued in connection with debt		94		94
Net loss			(27,970)	(27,970)
Ending balance, value at Dec. 31, 2020	$ 24	107,797	(92,158)	15,663
Ending balance, shares at Dec. 31, 2020	24,312,808
Stock-based compensation		3,381		3,381
Stock-based compensation, shares
Stock option exercises	$ 1	338		339
Stock option exercises, shares	144,233
Employee stock purchase plan		202		202
Employee stock purchase plan, shares	49,155
Proceeds from sales of common stock, net of offering costs, shares	94,808
Net loss			(1,955)	(1,955)
Common stock issued related to restricted stock units
Common stock issued related to restricted stock units, shares	25,000
Stock warrant exercises
Stock warrant exercises, shares	94,808
Ending balance, value at Dec. 31, 2021	$ 25	111,718	(94,113)	17,630
Ending balance, shares at Dec. 31, 2021	24,626,004
Stock-based compensation		4,218		4,218
Stock-based compensation, shares
Stock option exercises		35		35
Stock option exercises, shares	25,000
Employee stock purchase plan		171		171
Employee stock purchase plan, shares	69,884
Net loss			(9,021)	(9,021)
Stock warrant exercises		45		45
Stock warrant exercises, shares	632,231
Ending balance, value at Dec. 31, 2022	$ 25	$ 116,187	$ (103,134)	$ 13,078
Ending balance, shares at Dec. 31, 2022	25,353,119

Schedule of Future Lease Commitments (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Nov. 30, 2022	Oct. 31, 2020
Leases
Undiscounted lease payments	$ 201
2023	88
2024	90
2025	23
Less: Imputed interest	(19)
Total lease liabilities	$ 182	$ 188	$ 195

Summary of Stock Option Activity (Details) - Equity Option [Member] $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2022 USD ($) $ / shares shares
Offsetting Assets [Line Items]
Shares, Options Outstanding, Beginning Balance \| shares	3,513,719
Weighted Average Exercise Price, Options Outstanding, Beginning Balance \| $ / shares	$ 5.22
Shares, Issued \| shares	1,333,770
Weighted Average Exercise Price, Issued \| $ / shares	$ 3.72
Shares, Exercised \| shares	(25,000)
Weighted Average Exercise Price, Exercised \| $ / shares	$ 1.38
Shares, Forfeited/Cancelled \| shares	(420,197)
Weighted Average Exercise Price, Forfeited/Cancelled \| $ / shares	$ 6.04
Shares, Options Outstanding, Ending Balance \| shares	4,402,292
Weighted Average Exercise Price, Options Outstanding, Ending Balance \| $ / shares	$ 4.71
Weighted Average Remaining Contractual Term, Options Outstanding, Ending Balance	7 years 6 months
Aggregate Intrinsic Value, Options Outstanding, Ending Balance \| $	$ 884
Shares, Options Exercisable, Ending Balance \| shares	3,037,846
Weighted Average Exercise Price, Options Exercisable, Ending Balance \| $ / shares	$ 4.68
Weighted Average Remaining Contractual Term, Options Exercisable, Ending Balance	7 years
Aggregate Intrinsic Value, Options Exercisable, Ending Balance \| $	$ 800
Shares, Options Vested and Expected to Vest, Ending Balance \| shares	4,352,292
Weighted Average Exercise Price, Options Vested and Expected to Vest, Ending Balance \| $ / shares	$ 4.74
Weighted Average Remaining Contractual Term, Options Vested and Expected to Vest, Ending Balance	7 years 6 months
Aggregate Intrinsic Value, Options Vested and Expected to Vest, Ending Balance \| $	$ 812

Schedule of Property and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Property, Plant and Equipment [Abstract]
Computer hardware and software	$ 177	$ 157
Furniture and fixtures	112	106
Equipment	52	132
Leasehold improvements	71	71
Construction in progress	12
Property and equipment, gross	424	466
Less: accumulated depreciation and amortization	(352)	(351)
Property and equipment, net	$ 72	$ 115

Common Stock Warrants (Tables)

12 Months Ended

Dec. 31, 2022

Common Stock Warrants

Summary of Warrants Outstanding

Listed below is a summary of warrants outstanding as of December 31, 2022:

Summary of Warrants Outstanding

Description of Warrants	No. of Shares		Exercise Price
Placement Agent Warrants - IPO		414,000	$	7.50
SWK Warrants – Debt (Tranche #1)		51,239	$	5.86
SWK Warrants – Debt (Tranche #2)		18,141	$	6.62
Total		483,380	$	7.29 (Avg)

Summary of Rollforward of The Warrants Outstanding

A rollforward of the warrants outstanding is listed in the table below:

	No. of Shares
Balance as of the beginning of the year		1,554,826
Exercise of Placement Agent Warrants – 2017 Preferred Stock Offering		(1,067,242	)
Expiration of Placement Agent Warrants – 2017 Preferred Stock Offering		(4,204	)
Balance as of the end of the year		483,380

Schedule of Lease-related Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Nov. 30, 2022	Dec. 31, 2021	Oct. 31, 2020
Leases
Total leased assets	$ 188	$ 188	$ 104	$ 195
Operating lease liabilities, current	$ 75
Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Accrued liabilities
Operating lease liabilities, noncurrent	$ 107		$ 15
Total operating lease liabilities	$ 182	$ 188		$ 195

Schedule of Reconciliation of Statutory Federal Tax Rate (Details)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Benefit at statutory rate	(21.00%)	(21.00%)	(21.00%)
Permanent items (primarily warrants and stock compensation)	(3.30%)	(2.50%)	(0.50%)
State tax benefit	(8.70%)	(9.50%)	(7.70%)
Federal rate change
Other items
Increase in valuation allowance	33.00%	33.00%	29.20%
Income tax expense

Summary of Activity for Restricted Stock Awards (Details) - Restricted Stock Units (RSUs) [Member]	12 Months Ended
	Dec. 31, 2022 $ / shares shares
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Number of units outstanding, Beginning \| shares
Weighted average grant date fair value per unit outstanding, Beginning \| $ / shares
Number of units, granted \| shares	373,606
Weighted average grant date fair value per unit, granted \| $ / shares	$ 2.63
Number of units, vested \| shares
Weighted average grant date fair value per unit, vested \| $ / shares
Number of units, forfeited \| shares	(4,000)
Weighted average grant date fair value per unit, forfeited \| $ / shares	$ 2.63
Number of units outstanding, Ending \| shares	369,606
Weighted average grant date fair value per unit outstanding, Ending \| $ / shares	$ 2.63

Schedule of Assumptions Used to Calculate Fair Value of Options Granted (Details) - $ / shares	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Share-Based Payment Arrangement [Abstract]
Expected dividends
Expected volatility	70.00%		95.00%
Expected volatility, minimum		70.00%
Expected volatility, maximum		80.00%
Risk-free interest rate, minimum	1.50%	0.90%	0.40%
Risk-free interest rate, maximum	3.90%	1.40%	0.70%
Expected term	5 years 10 months 24 days	6 years	5 years 10 months 24 days
Weighted average fair value	$ 2.32	$ 5.64	$ 3.06