• Received FDA Fast Track Designation for pevifoscorvir sodium for the treatment of chronic hepatitis B virus infection
• HBeAg- cohort sample size increased to optimize powering; futility criteria not met
• Study drugs were well-tolerated by participants
• Topline data expected in 2027, guidance remains unchanged
  
  

 Aligos Therapeutics, Inc. (Nasdaq: ALGS, “Aligos”) a clinical stage biopharmaceutical company focused on improving patient outcomes through best-in-class therapies for liver and viral diseases, announced the first interim analysis results of the Phase 2 B-SUPREME study of pevifoscorvir sodium in participants with chronic hepatitis B virus (HBV) infection for the Part 2a (HBeAg- cohort) where the independent Data Safety Monitoring Review Board (DSMB) has recommended continuation of the study with an increase in sample size for this cohort in order to optimize statistical powering; futility criteria for the cohort was not met. Additionally, Aligos announced that the United States Food and Drug Administration (FDA) has granted Fast Track Designation to pevifoscorvir sodium, a potential best/first-in-class capsid assembly modulator (CAM-E) under investigation for the treatment of chronic hepatitis B virus (HBV) infection.

Interim Analysis

The study design for the Phase 2 B-SUPREME study includes pre-specified sample size re-estimations for both Parts 1a and 2a to ensure sufficient power to demonstrate a statistically significant treatment effect at the primary endpoint. The first pre-specified interim analysis of the Phase 2 B-SUPREME study was performed after approximately 60% of HBeAg- participants (N=34, Part 2a) reached Week 12 or later. In addition, safety data was reviewed for all participants enrolled in the study (N=174) at the time the interim analysis was performed.

Findings from the first interim analysis include:

• The DSMB recommended increasing the sample size of Part 2a from 74 currently enrolled to 100 participants. A futility analysis was performed; the prespecified futility criteria was not met, per the statistical analysis plan.
• The study drugs were well-tolerated with no clinically concerning laboratory, physical examination, vital sign, or ECG abnormalities. No viral breakthrough related to study drugs has been observed in the study to date.
  
  

Aligos remains blinded to participant-level data. Completion of enrollment in the HBeAg- cohort is expected in the second half of 2026. Currently, there are 74 participants enrolled in the HBeAg- cohort (Part 2a), with 103 participants enrolled in the HBeAg+ cohort (Part 1a). Topline data remains on track for 2027.

“We are encouraged by this recommendation from the DSMB to increase the sample size in order to increase the probability for success of the study’s primary endpoint,” stated Lawrence Blatt, Ph.D., M.B.A., Chairman, President, and Chief Executive Officer at Aligos Therapeutics. “We believe we can enroll the necessary study participants in the coming months, with topline data on track for 2027. Additionally, I am thrilled to share that pevifoscorvir sodium has been granted Fast Track Designation. Aligos’ mission since its founding has been to improve outcomes for patients with unmet needs in liver and viral diseases and being granted Fast Track Designation for pevifoscorvir sodium is the next step in our journey to make this a reality. As we progress the Phase 2 B-SUPREME study, we look forward to working with regulators to determine the appropriate path forward.”

Fast Track Designation

The FDA Fast Track Designation was supported by the 96-Week Phase 1 (NCT04536337) data evaluating pevifoscorvir sodium monotherapy in patients with chronic HBV infection, which were presented at The Liver Meeting® 2025, along with the 8-Week nucleoside analog follow-up data. This study demonstrated that pevifoscorvir sodium was well tolerated by study participants and the data demonstrated potential best-in-class reductions across clinically relevant viral markers.

Fast Track Designation is a process designed to facilitate the development and expedite the review of drugs to treat serious conditions and fill an unmet medical need. It enables more frequent meetings and communication with the FDA to ensure alignment on development plans and the collection of clinical data needed to support approval. Furthermore, clinical programs with Fast Track Designation may be eligible for Rolling Review, Accelerated Approval and Priority Review if relevant criteria are met. For conditions where an available treatment exists, a drug candidate must show some advantage over available therapy, such as superior effectiveness, to be granted Fast Track Designation¹.