An HBV cure program built on ingenuity, vision and experience

Assembly Bio has the goal and unique capabilities to improve cure rates for individuals with chronic hepatitis B (HBV) in our lifetime. Our strong scientific expertise in discovering small molecules targeting the HBV core protein has made us a leader in the field.

HBV—one of the world’s most prevalent diseases

Chronic hepatitis B virus (HBV) is a debilitating infectious disease of the liver that afflicts over 250 million people worldwide and is a leading cause of chronic liver disease and liver transplants. The Centers for Disease Control (CDC) reports approximately 1.5 million people in the US are chronically infected with HBV. It is a global epidemic that affects more people than hepatitis C virus (HCV) and HIV infection combined—with a higher morbidity and mortality rate. An estimated 500,000 to one million people worldwide die every year from HBV-related causes.

Currently there are no curative therapies available for HBV. The current standard of care is life-long suppressive treatment with medications that reduce, but do not eliminate, the virus, resulting in very low cure rates. The unmet need is enormous.

Our unique approach attacks HBV at multiple points in its lifecycle

Assembly Bio is advancing a number of Core Inhibitors (CIs) into preclinical and clinical development. Each of these CI candidates has been derived from distinct and novel chemical scaffolds to optimize their ability to effectively interrupt multiple points in the HBV lifecycle. Our CI drug candidates appear to disrupt both viral replication and prevent both establishment and replenishment of new cccDNA—unlike the current standard of care which can only inhibit production of new virus – and which may do so incompletely.1

1Marcellin, et al, AASLD 2014, Poster 1861

Advancing a novel class of oral antivirals to cure HBV.

Assembly Bio’s lead molecule, ABI-H0731 (731), has shown encouraging and potent activity across multiple HBV genotypes. 731 has been demonstrated to be well tolerated while achieving substantial reductions in both HBV DNA and RNA—distinguishing it from standard-of-care nucleoside therapy. Our 731 program is currently in Phase 2a clinical studies.

Our second CI candidate, ABI-H2158, has completed a Phase 1a study in healthy subjects and is currently being evaluated in a Phase 1b study in HBV patients. Additionally, we selected a third CI candidate, ABI-H3733, for clinical development. With our breakthrough scientific platform and deep research capabilities, we feel well positioned to be part of the curative therapy for individuals with chronic HBV.

More information about our clinical trials can be found at