Assembly Biosciences (ASMB) investor relations material

Strategic focus and partnerships

• Advancing four clinical-stage investigational therapies targeting serious viral diseases with high unmet need and market potential.

• Collaboration with Gilead provides expertise, funding, and late-stage development/commercialization support.

• Gilead holds opt-in rights at key clinical milestones, with Assembly eligible for significant milestones and royalties or profit-sharing.

• $100M upfront from Gilead, with potential for $330M milestones per program and $75M in extension payments.

• Cash position of ~$227M supports operations into 2028.

Recurrent genital herpes program (ABI-5366 & ABI-1179)

• Both are long-acting helicase-primase inhibitors (HPIs) showing superior potency to standard of care in preclinical and clinical studies.

• Phase 1b trials demonstrated 91–97% reduction in virologically confirmed lesions and HSV-2 shedding versus placebo.

• Clean safety profiles with no serious adverse events or discontinuations.

• Gilead exercised option to license both programs after positive Phase 1b results; Phase 2 initiation expected by end of 2026.

• Market opportunity exceeds $2B for a weekly, superior-efficacy therapy.

Hepatitis D (ABI-6250) and Hepatitis B (ABI-4334) programs

• ABI-6250 is an oral entry inhibitor for HDV, showing strong PK/PD and safety in Phase 1a; Phase 2 planned for late 2026.

• Addresses a major unmet need, as current HDV therapies are limited and require injections.

• ABI-4334, a next-generation capsid assembly modulator for HBV, showed potent antiviral activity and favorable safety in Phase 1b.

• Seeking partners for next-phase development of ABI-4334.