ABI-1179: An Investigational Long-Acting Helicase-Primase Inhibitor for Recurrent Genital Herpes

1. Executive Summary

ABI-1179 is an investigational, orally administered, long-acting small molecule antiviral agent currently under development for the treatment of recurrent genital herpes (RGH). Originated by Gilead Sciences, Inc. and now being advanced by Assembly Biosciences, Inc., ABI-1179 functions as a highly potent inhibitor of the herpes simplex virus (HSV) helicase-primase enzyme complex, a mechanism distinct from current standard-of-care nucleoside analogues.[1]

Preclinical studies have demonstrated ABI-1179's significant in vitro potency against both HSV-1 and HSV-2, including strains resistant to acyclovir. It has shown a higher barrier to resistance compared to acyclovir and a favorable pharmacokinetic profile in animal models, supporting the potential for infrequent dosing.[4] Interim results from the Phase 1a portion of the ongoing Phase 1a/b clinical trial (NCT06698575) in healthy volunteers indicated that ABI-1179 is well-tolerated and exhibits a mean plasma half-life of approximately four days, supporting a once-weekly oral dosing regimen. Notably, target plasma concentrations for antiviral activity were exceeded even at the lowest dose tested (50 mg).[1]