Shares of Assembly Biosciences Inc (NASDAQ:ASMB) climbed 14.8% on Friday after the company disclosed plans to expand clinical development of ABI-6250 into cholestatic liver disorders, specifically primary biliary cholangitis (PBC) and primary sclerosing cholangitis (PSC).
The firm said it intends to start a Phase 2 basket study evaluating ABI-6250 in cholestatic liver diseases in the first quarter of 2027. This program extension builds on a completed Phase 1a study and ongoing work targeting chronic hepatitis delta virus (HDV) infection.
Mechanism and rationale
ABI-6250 is an investigational, orally administered small-molecule that inhibits the sodium taurocholate co-transporting polypeptide (NTCP). NTCP is a membrane protein responsible for transporting bile acids into hepatocytes and also functions as the entry receptor for HDV. By blocking NTCP, ABI-6250 reduces uptake of bile acids into liver cells - a mechanism that is directly relevant to cholestatic conditions where bile acid accumulation contributes to liver inflammation and injury.
Financing to support development
Alongside the clinical expansion, Assembly Biosciences priced an underwritten offering of 3,358,602 shares of common stock at $26.50 per share. The transaction also includes pre-funded warrants exercisable to purchase up to 415,000 shares at a price of $26.499 each. The company expects gross proceeds before expenses to be approximately $100 million.
Participation in the offering comes from a mix of new and existing investors, the company said, naming Gilead Sciences Inc, Commodore Capital, Farallon Capital Management and other healthcare-focused investors. Assembly Biosciences indicated it will use net proceeds to advance clinical development of its pipeline candidates and for general corporate purposes.
The company anticipates the offering to close on or about May 26, 2026.
Clinical timeline and regulatory interaction
Assembly Biosciences also plans a Phase 2 clinical study of ABI-6250 in HDV, expected to begin in the fourth quarter of 2026. The company recently held a pre-IND meeting with the U.S. Food and Drug Administration to discuss its planned development in cholestatic liver diseases.
Information provided by the company outlines the sequencing of these development activities but does not offer additional clinical data or timelines beyond the dates and milestones referenced above.
Summary of key details
- Planned Phase 2 basket study for PBC and PSC targeted for Q1 2027.
- ABI-6250 is an oral NTCP inhibitor, mechanism aims to reduce bile acid uptake linked to cholestatic liver damage.
- Underwritten offering: 3,358,602 common shares at $26.50 and pre-funded warrants for up to 415,000 shares at $26.499; expected gross proceeds about $100 million; expected close on or about May 26, 2026.
- Phase 2 study in HDV planned for Q4 2026; company completed a pre-IND meeting with the FDA regarding cholestatic indications.