Assembly Biosciences Presents New Data Highlighting Hepatitis D Virus Entry Inhibitor 

Assembly Biosciences, Inc. recently announced new data for ABI-6250, the company’s orally bioavailable, small molecule hepatitis D virus (HDV) entry inhibitor candidate, featured in a poster presentation at the European Association for the Study of the Liver (EASL) Congress in Milan, Italy.

The poster presentation Preclinical profiling of ABI-6250, a novel orally bioavailable small-molecule therapeutic candidate for the treatment of chronic hepatitis D highlights preclinical data that support the advancement of ABI-6250 into Phase 1 clinical studies.

Chronic HDV infection is considered the most serious form of viral hepatitis, and can result in liver cirrhosis, liver cancer, decompensated liver disease or death. ABI-6250 acts to prevent the entry of HDV into cells by blocking access to the sodium taurocholate cotransporting polypeptide (NTCP) bile acid transporter, which is a clinically validated target for HDV infection.

Results from preclinical evaluation included in this presentation demonstrate that ABI-6250 can effectively inhibit, at low nanomolar levels, HDV infection of the most prevalent genotypes (HDV-1,-2 and-3) in HepG2-NTCP cells. ABI-6250 also effectively inhibited NTCP-mediated bile acid uptake and demonstrated selectivity for the NTCP bile transporter versus other transporters in vitro. In vivo, ABI-6250 elevated total bile acids, indicating NTCP target engagement without increasing biomarkers for inhibition of other transporters, supporting the selectivity seen in vitro and providing a biomarker for target engagement in Phase 1a studies. The presentation also describes the preclinical pharmacokinetic (PK) profile of ABI-6250, which supports low, once-daily oral dosing in individuals with chronic HDV.

“Serious viral hepatitis caused by chronic HDV infection impacts millions of people globally, with limited treatment options available for this devastating disease,” said Anuj Gaggar, MD, PhD, Chief Medical Officer of Assembly Bio. “The preclinical data presented at EASL support the advancement of ABI-6250 into clinical development and underscore the early promise of the therapy as a once-daily, oral treatment option, which would represent an important therapeutic innovation similar to what we’ve seen for other chronic viral infections such as hepatitis B virus and HIV. We look forward to moving ABI-6250 into the clinic later this year and sharing further data with the liver disease community.”

Assembly Biosciences is a biotechnology company dedicated to the development of innovative small-molecule antiviral therapeutics designed to change the path of serious viral diseases and improve the lives of patients worldwide. Led by an accomplished team of leaders in virologic drug development, Assembly Bio is committed to improving outcomes for patients struggling with the serious, chronic impacts of herpesvirus, hepatitis B virus (HBV) and hepatitis delta virus (HDV) infections. For more information, visit