Assembly Biosciences Reports Second Quarter 2026 Financial Results and Recent Updates

– Expanded ABI-6250 clinical development into cholestatic liver diseases, including primary biliary cholangitis (PBC) and primary sclerosing cholangitis (PSC) –

– Completed $115 million gross financing to support advancement of pipeline programs through key development milestones –

– GS-1179 (formerly ABI-1179) selected to advance in HSV HPI program, with Phase 2 initiation expected by year-end 2026 –

– Cash runway projected into 2029, including first $75 million Gilead collaboration extension payment due in Q4 2026 –

SOUTH SAN FRANCISCO, Calif., Aug. 13, 2026 (GLOBE NEWSWIRE) -- Assembly Biosciences, Inc. (Nasdaq: ASMB), a biotechnology company developing innovative therapeutics targeting serious viral and liver diseases, today reported financial results for the second quarter ended June 30, 2026, and recent business updates.

“During the second quarter, we advanced several important strategic priorities, including expanding ABI-6250 into cholestatic liver diseases and strengthening our balance sheet through a successful financing to support the continued advancement of our pipeline," said Jason Okazaki, chief executive officer and president of Assembly Bio. "We were also pleased to receive Gilead’s clinical development plan for the HSV helicase primase inhibitor program, which includes plans for GS-1179 to advance into a Phase 2 clinical trial by the end of 2026. The plan also contemplates evaluation of GS-1179 across broader prevention settings, including in connection with HIV PrEP, further reinforcing the potential opportunity for this program. We expect to make our determination on whether to opt-in to the U.S. cost and profit share soon after we receive the commercial cost estimates from Gilead, which will complete the opt-in package.”

Second Quarter 2026 and Recent Updates

Anticipated Milestones and Events

Upcoming Conferences

GS-1179 and ABI-6250 are investigational product candidates that have not been approved anywhere globally, and their safety and efficacy have not been established. GS-1179 is exclusively licensed to Gilead under the collaboration between Assembly Bio and Gilead, and Gilead has the sole right and responsibility for further clinical development and commercialization of the HSV HPI program.

Second Quarter 2026 Financial Results

About Assembly Biosciences

Assembly Biosciences is a biotechnology company dedicated to the development of innovative small-molecule therapeutics aimed at advancing the treatment paradigm of serious viral and liver diseases and improving the lives of patients worldwide. Led by an accomplished leadership team in antiviral and liver disease drug development, Assembly Bio is committed to improving outcomes for people living with the chronic impacts of herpesvirus, hepatitis delta virus (HDV) infections, cholestatic liver diseases and hepatitis B virus (HBV). For more information, visit assemblybio.com.

Forward-Looking Statements

The information in this press release contains forward-looking statements that are subject to certain risks and uncertainties that could cause actual results to materially differ. These risks and uncertainties include: Assembly Bio’s ability to realize the potential benefits of its collaboration with Gilead, including all financial aspects of the collaboration and equity investments; Assembly Bio’s ability to initiate and complete clinical studies involving its therapeutic product candidates, including studies contemplated by Assembly Bio’s collaboration with Gilead, including studies conducted by Gilead, in the currently anticipated timeframes or at all; safety and efficacy data from clinical or nonclinical studies may not warrant further development of product candidates; clinical and nonclinical data may not differentiate product candidates from other companies’ candidates; Assembly Bio’s ability to maintain financial resources and secure additional funding necessary to continue its research activities, clinical studies, and other business operations; potential effects of changes in government regulation; results of nonclinical studies may not be representative of disease behavior in a clinical setting and may not be predictive of the outcomes of clinical studies; and other risks identified from time to time in Assembly Bio’s reports filed with the U.S. Securities and Exchange Commission (the SEC). You are urged to consider statements that include the words may, will, would, could, should, might, believes, hopes, estimates, projects, potential, expects, plans, anticipates, intends, continues, forecast, designed, goal or the negative of those words or other comparable words to be uncertain and forward-looking. Assembly Bio intends such forward-looking statements to be covered by the safe harbor provisions contained in Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended. More information about Assembly Bio’s risks and uncertainties are more fully detailed under the heading “Risk Factors” in Assembly Bio’s filings with the SEC, including its most recent Annual Report on Form 10-K, Quarterly Reports on Form 10-Q and Current Reports on Form 8-K. Except as required by law, Assembly Bio assumes no obligation to update publicly any forward-looking statements, whether as a result of new information, future events or otherwise.

Contacts:

Investors:

Patrick Till

Meru Advisors

(484) 788-8560

investor_relations@assemblybio.com

Media:

Jamie Strachota

Sam Brown LLC

(703) 819-7647

ASMBMedia@sambrown.com