Aligos Therapeutics completes enrolment in Phase 2 HBV study
Aligos Therapeutics has announced the completion of enrolment in the B-SUPREME Phase 2 study of pevifoscorvir sodium, a capsid assembly modulator in development for chronic hepatitis B virus (HBV) infection. The South San Francisco company said a total of 245 participants have been enrolled across two cohorts: 131 HBeAg-positive participants in Part 1a and 114 HBeAg-negative participants in Part 2a. Topline safety and efficacy data are expected in the late third quarter of 2027.
The trial, registered as NCT06963710, is a randomised, double-blind, active-controlled study comparing pevifoscorvir sodium monotherapy against tenofovir disoproxil fumarate (TDF) over 48 weeks in treatment-naive adults. The primary endpoint in the HBeAg-positive cohort is HBV DNA below the lower limit of quantification at a threshold of 10 IU/mL, while the HBeAg-negative cohort uses the more stringent target-not-detected criterion. Secondary endpoints include reductions in HBV surface antigen and other viral markers.
Aligos noted that enrolment in Part 1a exceeded the original target, which means the planned second interim analysis for sample-size re-estimation will be skipped. That is a logistical consequence of over-enrolment rather than a scientific readout, and it does not change the 48-week efficacy endpoints.
About the candidate
Pevifoscorvir sodium, previously known as ALG-000184, is an oral small-molecule capsid assembly modulator of the E-type class, derived from intellectual property originally licensed from the laboratory of Raymond Schinazi at Emory University. Phase 1 data reported by Aligos showed the compound was well-tolerated at doses up to 300 mg once daily for up to 96 weeks, with linear pharmacokinetics and reductions across multiple HBV markers, including HBV DNA, RNA, HBsAg, HBeAg, and HBcrAg. The FDA, EMA, and China's NMPA have all acknowledged a regulatory path for the compound through the chronic suppressive pathway.
Lawrence Blatt, chairman, president and chief executive of Aligos, said completion of enrolment "advances our mission to develop transformative therapies for chronic hepatitis B virus infection and to reduce the burden of end-stage liver disease and hepatocellular carcinoma."
Market context
The chronic HBV space is one of the more active areas in antiviral drug development, driven by a large global patient population: the World Health Organisation estimates 240 million people live with chronic HBV infection, with around 1.1 million deaths attributed to related complications in 2024. Existing nucleoside and nucleotide analogues such as TDF and entecavir suppress viral replication effectively but rarely achieve functional cure, leaving a significant unmet need for agents that can reduce cccDNA or induce HBsAg loss.
Capsid assembly modulators have attracted particular attention as potential components of combination regimens aimed at functional cure. Several large pharmaceutical groups and specialist biotechs are active in this space, including programmes exploring CAMs alongside RNA interference agents and immune modulators. Aligos's decision to run B-SUPREME as a monotherapy comparison against TDF will provide a clean efficacy signal, though combination strategies may ultimately define how pevifoscorvir sodium is used commercially if it reaches approval. Investors will focus on the HBsAg reduction data when topline results arrive, as antigen decline is increasingly accepted by regulators as a surrogate for functional cure potential.