Assembly Biosciences (ASMB) Jefferies Global Healthcare Conference 2026 summary

Key program updates and catalysts

• Two HSV molecules, ABI-5366 and ABI-1179, showed strong Phase I-B proof of concept; Gilead has opted in and now leads development and commercialization, with a clinical development plan expected soon and a mid-year opt-in decision on a 40/60 US profit share.

• ABI-6250 for hepatitis delta showed positive Phase I-A data; Phase II study to start by end of year with data expected in the second half of next year.

• ABI-6250 program expanded to include PBC and PSC, supported by KOL feedback and a recent pre-IND meeting with FDA; funding secured through end of Phase II.

• Phase II studies for PBC and PSC to begin Q1 2027, with data anticipated in the first half of 2028.

• Commercial and development decisions for all programs are data-driven, with flexibility for standalone or combination therapies and ongoing discussions with Gilead regarding opt-in logistics.

Clinical strategy and trial design

• Gilead's clinical development plan for HSV programs will inform cost, profit share, and milestone decisions, with a focus on long-term value and NPV analysis.

• ABI-6250's mechanism as an NTCP inhibitor supports its use in cholestatic liver diseases; basket Phase II study will enroll both PBC and PSC patients for operational efficiency and faster proof of concept.

• The PBC/PSC trial will have three arms: standalone ABI-6250, third-line on top of PPAR, and a focus on biochemical endpoints (alkaline phosphatase, ALT, bilirubin), non-invasive fibrosis markers, and quality of life.

• For PBC, biochemical endpoints are approvable; for PSC, clinical outcomes are required, but Phase II will focus on directional biomarker changes.

• Safety profile for ABI-6250 is strong, with no significant pruritus observed; ongoing monitoring will focus on intrahepatic bile acid and IL31 levels.

Commercial positioning and future plans

• ABI-6250 offers flexibility as a standalone or add-on to PPARs, with potential for co-formulation and broad application in cholestatic liver diseases.

• Commercial strategy for PSC is data-dependent, with potential for first-mover advantage in a largely untapped market.

• Gilead holds opt-in rights for ABI-6250 across indications, with opt-ins triggered after Phase II data; logistics for multiple indications are under discussion.

• Expansion into other rare cholestatic liver diseases is possible after proof of concept in PBC and PSC.

• Pricing strategy will consider dose, indication, and market comparables, with flexibility due to low cost of goods for small molecules.