N-Acetyl Glutamate Synthetase Deficiency

Product sales and royalty revenue of $7.0 million up 118% from Q3 2022, representing the eleventh straight quarter of sequential product sales and royalty revenue growthGenerated $0.9 million in positive cash flow from operations; ended quarter with $22.1 million of cash on handAcquired ultra-rare disease product Nitisinone CapsulesManagement to hold conference call today at 4:30pm ET DEER PARK, Ill., Nov. 09, 2023 (GLOBE NEWSWIRE) -- Eton Pharmaceuticals, Inc (“Eton” or “the Company”) (Nasdaq: ETON), an innovative pharmaceutical company focused on developing and commercializing treatments for rare diseases, today reported financial results for the quarter ended September 30, 2023. “The momentum continues for Eton, and we’re proud to report our eleventh straight quarter of product sales and royalty revenue growth, which has allowed us to reach cash flow break-even ahead of schedule. Sales of ALKINDI SPRINKLE® and Carglumic Acid remain strong, and we recently added a fourth commercial rare disease product to our portfolio, Nitisinone Capsules, which we expect to launch in early 2024,” said Sean Brynjelsen, CEO of Eton Pharmaceuticals. “Reaching cash flow break-even is an important milestone on our journey to becoming a highly profitable and industry leading rare disease company. I am proud of the hard work and dedication from our employees that made it possible. With strong organic growth prospects for our existing commercial products, the potential near-term launches of Nitisinone and ET-400, plus a strong balance sheet and favorable M&A environment, I couldn’t be more excited about Eton’s outlook for 2024 and beyond,” concluded Brynjelsen. Third Quarter and Recent Business Highlights Eleventh straight quarter of sequential growth in product sales and royalty revenue. Eton reported third quarter 2023 product sales and royalty revenue of $7.0 million, representing 118% growth over the prior year period and 8% growth over the second quarter of 2023. Recorded positive cash flow from operations solely from product sales and royalty revenue. During the quarter, cash on hand increased from $21.6 million to $22.1 million. Strong growth in product sales driven by ALKINDI SPRINKLE and Carglumic Acid. Both products posted strong year-over-year and quarter-over-quarter sales growth. The Company expects to launch an ALKINDI SPRINKLE physician sampling program in the coming weeks, which is expected to further accelerate the product’s growth. Acquired FDA-approved ultra-rare disease product Nitisinone. In October, Eton acquired Nitisinone capsules which will be Eton’s fourth commercial product, moving the company closer to its goal of reaching ten commercial products by the end of 2025. Eton expects to launch the product during the first quarter of 2024. First full quarter of commercial availability for Betaine Anhydrous. The launch of Betaine resulted in a significant increase in the company’s interactions with metabolic geneticists, which is expected to help drive Betaine revenue as well as potentially benefit Carglumic Acid and the company’s soon-to-be-launched Nitisinone product. Held pre-NDA meeting with FDA regarding product candidate ET-400. Last week, Eton held a pre-NDA meeting with the FDA regarding ET-400. Based on feedback from the meeting, the company plans to run an additional bioequivalence study and submit the NDA in the middle of 2024. ET-400 is a proprietary liquid formulation of hydrocortisone that, if approved, would complement ALKINDI SPRINKLE by providing patients with an additional treatment option. The Company believes that the combined peak sales of ET-400 and ALKINDI SPRINKLE could exceed $50 million annually. Third Quarter Financial Results Net Revenue: Net sales for the third quarter of 2023 were $7.0 million compared with $3.2 million in the prior year period, an increase of 118%. Net sales were comprised entirely of product sales and royalties in both periods. The year-over-year increase was primarily driven by growth in ALKINDI SPRINKLE and Carglumic Acid tablets. Product sales and royalty revenue for the third quarter of 2023 were up 8% over the second quarter of 2023. Gross Profit: Gross profit for the third quarter of 2023 was $4.4 million compared with $2.0 million in the prior year period. Research and Development (R&D) Expenses: R&D expenses for the third quarter of 2023 were $0.6 million compared to $0.7 million in the prior year period. The decrease was primarily due to decreased expenses associated with products sold to Dr. Reddy's in 2022. General and Administrative (G&A) Expenses: G&A expenses for the third quarter of 2023 were $4.3 million compared to $4.2 million in the prior year period. The slight increase in G&A expenses was mainly due to increased employee-related expenses related to sales force expansion offset by decreased sales and marketing expenses associated with third party sales commissions. Net Loss: Net loss for the third quarter of 2023 was $0.6 million or $0.02 per basic and diluted share compared to a net loss of $3.0 million, or $0.12 per basic and diluted share, in the prior year period. Cash Position: As of September 30, 2023, the Company had cash and cash equivalents of $22.1 million. Conference Call and Webcast Information As previously announced, Eton will host its third quarter 2023 conference call as follows: Date:Thursday, November 9, 2023Time:4:30 p.m. ET (3:30 p.m .CT)Register* (Audio Only) Click Here In addition to taking live questions from participants on the conference call, management will be answering emailed questions from investors. Investors can email questions to: investorrelations@etonpharma.com The live webcast can be accessed on the Investors section of Eton’s website at ir.etonpharma.com. An archived webcast will be available on Eton’s website approximately two hours after the completion of the event and for 30 days thereafter. * Conference call participants should register to obtain their dial-in and passcode details. Please be sure to register using a valid email address. Forward-Looking Statements Statements contained in this press release regarding matters that are not historical facts are "forward-looking statements" within the meaning of the Private Securities Litigation Reform Act of 1995, including statements associated with the expected ability of Eton to undertake certain activities and accomplish certain goals and objectives. These statements include but are not limited to statements regarding Eton’s business strategy, Eton’s plans to develop and commercialize its product candidates, the safety and efficacy of Eton’s product candidates, Eton’s plans and expected timing with respect to regulatory filings and approvals, and the size and growth potential of the markets for Eton’s product candidates. Because such statements are subject to risks and uncertainties, actual results may differ materially from those expressed or implied by such forward-looking statements. Words such as "believes," "anticipates," "plans," "expects," "intends," "will," "goal," "potential" and similar expressions are intended to identify forward-looking statements. These forward-looking statements are based upon Eton’s current expectations and involve assumptions that may never materialize or may prove to be incorrect. Actual results and the timing of events could differ materially from those anticipated in such forward-looking statements as a result of various risks and uncertainties, which include, without limitation, risks associated with the process of discovering, developing and commercializing drugs that are safe and effective for use as human therapeutics, and in the endeavor of building a business around such drugs. These and other risks concerning Eton’s development programs and financial position are described in additional detail in Eton’s filings with the Securities and Exchange Commission. All forward-looking statements contained in this press release speak only as of the date on which they were made. Eton undertakes no obligation to update such statements to reflect events that occur or circumstances that exist after the date on which they were made. About Eton Pharmaceuticals Eton is an innovative pharmaceutical company focused on developing, acquiring, and commercializing products to address unmet needs in patients suffering from rare diseases. The Company currently has four FDA-approved rare disease products, ALKINDI SPRINKLE® for the treatment of pediatric adrenocortical insufficiency, Carglumic Acid for the treatment of hyperammonemia due to N-acetylglutamate synthase (NAGS) deficiency, Betaine Anhydrous for the treatment of homocystinuria, and Nitisinone for the treatment of hereditary tyrosinemia type 1. The Company has three additional product candidates in late-stage development: ET-400 for the treatment of adrenocortical insufficiency, ET-600 for the treatment of diabetes insipidus, and ZENEO® hydrocortisone autoinjector for the treatment of adrenal crisis. For more information, please visit our website at www.etonpharma.com. Investor Relations:Lisa M. Wilson, In-Site Communications, Inc.T: 212-452-2793E: lwilson@insitecony.com Eton Pharmaceuticals, Inc.Condensed Statements of Operations(In thousands, except per share amounts)(Unaudited) For the three months ended For the nine months ended September 30, September 30, September 30, September 30, 2023 2022 2023 2022 Revenues: Licensing revenue $— $— $5,500 $5,000 Product sales and royalties 7,028 3,219 18,829 7,753 Total net revenues 7,028 3,219 24,329 12,753 Cost of sales: Licensing revenue — — — 990 Product sales and royalties 2,625 1,201 6,898 3,805 Total cost of sales 2,625 1,201 6,898 4,795 Gross profit 4,403 2,018 17,431 7,958 Operating expenses: Research and development 615 744 2,275 3,052 General and administrative 4,336 4,169 14,355 14,228 Total operating expenses 4,951 4,913 16,630 17,280 Income (loss) from operations (548) (2,895) 801 (9,322) Other income (expense): Other income — — 800 — Interest and other expense, net (31) (150) (281) (611)Total other income (expense) (31) (150) 519 (611) Income (loss) before income tax expense (579) (3,045) 1,320 (9,933) Income tax expense — — — — Net income (loss) $(579) $(3,045) $1,320 $(9,933)Net income (loss) per share, basic $(0.02) $(0.12) $0.05 $(0.40)Weighted average number of common shares outstanding, basic 25,719 25,365 25,613 25,066 Net income (loss) per share, diluted $(0.02) $(0.12) $0.05 $(0.40)Weighted average number of common shares outstanding, diluted 25,719 25,365 26,002 25,066 Eton Pharmaceuticals, Inc.Condensed Balance Sheets(in thousands, except share and per share amounts) September 30, 2023 December 31, 2022 (Unaudited) Assets Current assets: Cash and cash equivalents $22,070 $16,305 Accounts receivable, net 3,495 1,852 Inventories 1,051 557 Prepaid expenses and other current assets 541 1,290 Total current assets 27,157 20,004 Property and equipment, net 38 72 Intangible assets, net 4,210 4,754 Operating lease right-of-use assets, net 109 188 Other long-term assets, net 12 12 Total assets $31,526 $25,030 Liabilities and stockholders’ equity Current liabilities: Accounts payable $1,712 $1,766 Current portion of long-term debt 1,540 1,033 Accrued liabilities 7,141 3,662 Total current liabilities 10,393 6,461 Long-term debt, net of discount and including accrued fees 4,197 5,384 Operating lease liabilities, net of current portion 44 107 Total liabilities 14,634 11,952 Commitments and contingencies (Note 11) Stockholders’ equity Common stock, $0.001 par value; 50,000,000 shares authorized; 25,658,396 and 25,353,119 shares issued and outstanding at September 30, 2023 and December 31, 2022, respectively 26 25 Additional paid-in capital 118,680 116,187 Accumulated deficit (101,814) (103,134)Total stockholders’ equity 16,892 13,078 Total liabilities and stockholders’ equity $31,526 $25,030 Eton Pharmaceuticals, Inc.Condensed Statements of Cash Flows(In thousands)(Unaudited) Nine months ended Nine months ended September 30, 2023 September 30, 2022 Cash flows from operating activities Net income (loss) $1,320 $(9,933) Adjustments to reconcile net income (loss) to net cash provided by operating activities: Stock-based compensation 2,387 3,332 Depreciation and amortization 626 1,522 Debt discount amortization 90 96 Changes in operating assets and liabilities: Accounts receivable (1,643) 3,973 Inventories (494) 69 Prepaid expenses and other assets 749 2,129 Accounts payable (52) (720)Accrued liabilities 3,445 1,513 Net cash provided by operating activities 6,428 1,981 Cash flows from investing activities Purchases of product license rights — (2,750)Purchases of property and equipment — (26)Net cash used in investing activities — (2,776) Cash flows from financing activities Repayment of long-term debt (770) (385)Proceeds from employee stock purchase plan and stock option exercises 288 152 Payment of tax withholding related to net share settlement of stock option exercises (181) — Net cash used in financing activities (663) (233) Change in cash and cash equivalents 5,765 (1,028)Cash and cash equivalents at beginning of period 16,305 14,406 Cash and cash equivalents at end of period $22,070 $13,378 Supplemental disclosures of cash flow information Cash paid for interest $638 $545 Cash paid for income taxes $— $— Supplemental disclosures of non-cash transactions Adjustment of operating lease right-of-use assets and liabilities due to tenant allowance $29 $—

DEER PARK, Ill., Oct. 30, 2023 (GLOBE NEWSWIRE) -- Eton Pharmaceuticals, Inc. (Nasdaq: ETON), an innovative pharmaceutical company focused on developing, acquiring, and commercializing products to address unmet needs in patients suffering from rare diseases, today announced that it will report third quarter 2023 financial results on Thursday, November 9, 2023. Management will host a conference call and live audio webcast to discuss these results at 4:30 p.m. ET (3:30 p.m. CT). Register* (Audio Only) Click here In addition to taking live questions from participants on the conference call, management will be answering emailed questions from investors. Investors can email questions to: investorrelations@etonpharma.com.The live webcast can be accessed on the Investors section of Eton’s website at https://ir.etonpharma.com/. An archived webcast will be available on Eton’s website approximately two hours after the completion of the event and for 30 days thereafter. * Conference call participants should register to obtain their dial-in and passcode details. Please be sure to register using a valid email address. About Eton Pharmaceuticals Eton is an innovative pharmaceutical company focused on developing, acquiring, and commercializing products to address unmet needs in patients suffering from rare diseases. The Company currently has four FDA-approved rare disease products, ALKINDI SPRINKLE® for the treatment of pediatric adrenocortical insufficiency, Carglumic Acid for the treatment of hyperammonemia due to N-acetylglutamate synthase (NAGS) deficiency, Betaine Anhydrous for the treatment of homocystinuria, and Nitisinone for the treatment of hereditary tyrosinemia type 1. The Company has four additional product candidates in late-stage development: ET-400 for the treatment of adrenocortical insufficiency, ET-600 for the treatment of diabetes insipidus, ZENEO® hydrocortisone autoinjector for the treatment of adrenal crisis, and dehydrated alcohol injection for the treatment of methanol poisoning. For more information, please visit our website at www.etonpharma.com. Investor Relations: Lisa M. Wilson, In-Site Communications, Inc.T: 212-452-2793E: lwilson@insitecony.com Source: Eton Pharmaceuticals

Expect Q1 2024 product launch Nitisinone market estimated to be more than $50 million annually Eton will offer Eton Cares support program to all patients DEER PARK, Ill., Oct. 04, 2023 (GLOBE NEWSWIRE) -- Eton Pharmaceuticals (“Eton” or “the Company”) (Nasdaq: ETON), an innovative pharmaceutical company focused on developing, acquiring, and commercializing products to address unmet needs in patients suffering from rare diseases, today announced it has entered into an agreement to acquire an abbreviated new drug application for Nitisinone Capsules via Oakrum Pharma, LLC’s Chapter 11 bankruptcy proceeding. The transaction has been approved by the bankruptcy court and is expected to be effective on October 12, 2023. The acquired product was approved by the U.S. Food and Drug Administration (FDA) in May of 2023 for the treatment of hereditary tyrosinemia type 1 (HT-1) in combination with dietary restriction of tyrosine and phenylalanine. It is estimated that less than 500 patients in the United States suffer from this ultra-rare condition. “With a patient population of less than 500, Nitisinone is another opportunity for Eton to deliver on its mission of providing medicines to and supporting patients and families with rare conditions. Nitisinone is our fourth FDA-approved product, and further advances us toward our goal of having ten commercial rare disease products on the market by the end of 2025. Nitisinone also shares the same metabolic geneticist prescriber base as our Carglumic Acid and Betaine products, so this is an attractive opportunity to leverage our existing sales force and relationships with prescribers,” said Sean Brynjelsen, CEO of Eton Pharmaceuticals. Eton expects to launch the product in the first quarter of 2024 and plans to offer its Eton Cares support program to all patients. The program is designed to help patients access treatment, providing prescription fulfillment services, insurance benefits investigation, educational support, and help in obtaining financial assistance for qualified patients, among other services. The current Nitisinone market is estimated to be over $50 million annually, and Eton believes the Company’s commercial advantages, including its Eton Cares program, existing relationships with prescribers, and experienced sales force should allow it to capture a meaningful percentage of the market. USE and IMPORTANT SAFETY INFORMATION What is Nitisinone? Nitisinone is a prescription medicine used to treat adults and children with a hereditary disease called tyrosinemia type 1 (HT-1). Nitisinone should be taken along with a diet limiting tyrosine and phenylalanine. What is the most important information I should know about Nitisinone? Tell your doctor or nurse right away if you have any of these symptoms with Nitisinone: Increased levels of plasma tyrosine, eye symptoms, developmental delay, and skin changes: Inadequate restriction of tyrosine and phenylalanine intake can result in raising plasma tyrosine levels. Plasma tyrosine levels above 500 micromol/L may lead to eye signs and symptoms like corneal ulcers, corneal cloudiness, inflammation of the cornea (keratitis), pink eye (conjunctivitis), eye pain, and sensitivity to light (photophobia), intellectual disability and developmental delay or painful thickening of the skin (hyperkeratotic plaques) on the soles and palms. Your healthcare provider should not adjust Nitisinone dosage in order to lower the levels of tyrosine in the blood. Changes in blood pro > You may develop a reduction in the number of white blood cells, which form part of the immune system (leukopenia) and abnormally low levels of platelets, which help the blood to clot (severe thrombocytopenia). Do not take Nitisinone if: you are allergic to nitisinone or any other ingredients. Stop using Nitisinone and get medical help right away if you have any symptoms of a serious allergic reaction, including swelling of the face, lips, tongue, or throat; problems breathing or swallowing; severe rash or itching; fainting or feeling dizzy; or very rapid heartbeat. Before taking Nitisinone, tell your doctor if you: are pregnant or plan to become pregnant. Nitisinone may harm your unborn baby. Tell your doctor if you become pregnant or suspect you are pregnant during treatment with Nitisinone. are breastfeeding or plan to breastfeed. It is not known if Nitisinone passes into your breast milk. Talk to your doctor about the best ways to feed your baby during treatment with Nitisinone. are aged 65 and older. Your doctor may need to adjust the dose of Nitisinone based on your requirements. are taking other medicines since Nitisinone can interfere with their effect. Tell your doctor about all the medicines you take, including prescription and over-the-counter medicines, vitamins, dietary and herbal supplements. What are the possible side effects of Nitisinone? The most common side effects of Nitisinone (≥1%) include high tyrosine levels, low platelets (thrombocytopenia) or white cells in the blood (leukopenia), and complaints related to the eyes, including pink eye (conjunctivitis), corneal cloudiness, inflammation of the cornea, eye pain and extreme sensitivity to light (photophobia), nosebleed (epistaxis), itching (pruritus), skin inflammation (exfoliative dermatitis), rash (maculopapular rash), dry skin and hair loss (alopecia). For more detailed information, please refer to the full Prescribing Information. To report a suspected adverse event related to Nitisinone, contact Eton Pharmaceuticals, Inc. at: 1-855-224-0233 or the US Food and Drug Administration at or call 1-800-FDA-1088. About Eton Pharmaceuticals Eton is an innovative pharmaceutical company focused on developing, acquiring, and commercializing products to address unmet needs in patients suffering from rare diseases. The Company currently has three commercial rare disease products, ALKINDI SPRINKLE® for the treatment of pediatric adrenocortical insufficiency, Carglumic Acid for the treatment of hyperammonemia due to N-acetylglutamate synthase (NAGS) deficiency, and Betaine Anhydrous for the treatment of homocystinuria. The Company has four additional product candidates in late-stage development: dehydrated alcohol injection, which has received Orphan Drug Designation for the treatment of methanol poisoning, ZENEO® hydrocortisone autoinjector for the treatment of adrenal crisis, ET-400 for the treatment of adrenocortical insufficiency, and ET-600 for the treatment of diabetes insipidus. For more information, please visit our website at . Forward-Looking Statements Statements contained in this press release regarding matters that are not historical facts are "forward-looking statements" within the meaning of the Private Securities Litigation Reform Act of 1995, including statements associated with the expected ability of Eton to undertake certain activities and accomplish certain goals and objectives. These statements include but are not limited to statements regarding Eton’s business strategy, Eton’s plans to develop and commercialize its product candidates, the safety and efficacy of Eton’s product candidates, Eton’s plans and expected timing with respect to regulatory filings and approvals, and the size and growth potential of the markets for Eton’s product candidates. Because such statements are subject to risks and uncertainties, actual results may differ materially from those expressed or implied by such forward-looking statements. Words such as "believes," "anticipates," "plans," "expects," "intends," "will," "goal," "potential" and similar expressions are intended to identify forward-looking statements. These forward-looking statements are based upon Eton’s current expectations and involve assumptions that may never materialize or may prove to be incorrect. Actual results and the timing of events could differ materially from those anticipated in such forward-looking statements as a result of various risks and uncertainties, which include, without limitation, risks associated with the process of discovering, developing and commercializing drugs that are safe and effective for use as human therapeutics, and in the endeavor of building a business around such drugs. These and other risks concerning Eton’s development programs and financial position are described in additional detail in Eton’s filings with the Securities and Exchange Commission. All forward-looking statements contained in this press release speak only as of the date on which they were made. Eton undertakes no obligation to update such statements to reflect events that occur or circumstances that exist after the date on which they were made. Investor Relations: Lisa M. Wilson, In-Site Communications, Inc. T: 212-452-2793 E: lwilson@insitecony.com Source: Eton Pharmaceuticals.