Assembly Biosciences (NASDAQ: ASMB) is a clinical-stage biopharmaceutical company focused on developing antiviral therapeutics. Since its inception, the company has generated no revenue from product sales, funding operations through equity financings and collaboration agreements rather than commercial activity. Its primary commercial relationship is with Gilead Sciences, which held approximately 29.9% of ASMB's outstanding voting common stock as of late 2024 and exercises board designation rights. Revenue is recognized through a collaboration arrangement with Gilead under a cost-based input method tied to research and development services. In December 2025, Gilead exercised its option to exclusively license ASMB's helicase-primase inhibitor (HPI) program, representing a material milestone under the 2023 Gilead Collaboration Agreement. The company was audited by its current auditor since 2015 and files on a calendar fiscal year basis. Cash is held in cash equivalents and marketable securities, with no disclosed debt financing since its 2010 IPO era.

Revenue model

Collaboration revenue from Gilead Sciences, recognized over time using a cost-based input method tied to R&D services performed under the 2023 Gilead Collaboration Agreement. No product sales revenue as of FY2025. Additional revenue events include option exercises by Gilead, such as the December 2025 HPI program license.

Products and services

Helicase-primase inhibitor (HPI) program, exclusively licensed to Gilead Sciences in December 2025. Antiviral drug discovery and development services conducted under the Gilead collaboration. AI is used in a limited capacity to assist in selecting chemical compounds for evaluation.

Customers and end markets

Gilead Sciences is the sole disclosed collaboration partner and the source of all collaboration revenue. Gilead held approximately 29.9% of ASMB's outstanding voting common stock as of December 2024 and designated two directors to ASMB's board. End market is antiviral therapeutics.

Value-chain role

Preclinical and clinical-stage drug discovery and development organization. ASMB conducts nonclinical and clinical research, then licenses programs to larger pharmaceutical partners such as Gilead for further development and commercialization.

Geographic exposure

U.S.-headquartered. Engages European contract research organizations (CROs) for clinical trials, bringing EU GDPR and UK GDPR obligations into scope. EU AI Act compliance is under active assessment as of the filing date (2026-03-19).

Source: SEC 10-K, filed 2026-03-19

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