Vaxart reports PhII defeat for a legacy antiviral from Aviragen — shares slide

When Vaxart picked Aviragen Therapeutics for the reverse merger that got it on the Nasdaq, the South San Francisco biotech highlighted a Phase II treatment for condyloma caused by HPV as particularly interesting among the antiviral programs it was inheriting. Seven months later, Vaxart is finding out the drug, like many of Aviragen’s previous therapies, might be a failure after all.

Wouter Latour

Vaxart reports today that teslexivir (BTA074) has flunked the primary efficacy endpoint: complete clearance of baseline condyloma, or small bumps on genitals, by week 16. In a double blind trial evaluating the teslexivir 5% gel in 218 patients, only 30.6% of the drug arm — not a statistically significant difference from 23.3% in the placebo group — completely cleared baseline condyloma by week 16.

The news sent Vaxart’s stock $VXRT down 18.7% in pre-market trading, despite the company’s efforts to shine what positive light they had on the data.

Some of the patients who cleared all condyloma within the predetermined period have entered a three-month follow-up period to assess the recurrence efficacy endpoints. That’s part of the secondary efficacy endpoints, which include various assessments of clearance, time to clearance, and wart area reduction for both baseline warts and post-baseline emergent warts.

The company attempted to salvage the situation with a preliminary subgroup analysis of female patients and those with large condylomas, while noting neither of the results are significant. Female patients on teslexivir saw a 37.5% clearance rate versus 23.3% among those on placebo; for patients with large condylomas, the numbers were 30.0% (drug) and 15.4% (placebo).

“While this trial did not achieve the primary efficacy endpoint, we were pleased with the benign safety profile and positive efficacy trends in certain patient subpopulations,” said CEO Wouter Latour in a statement. “We are currently in the follow-up phase of the study and data collection should continue for a few more weeks. During this period, we will conduct further analysis of the results, which should inform us about the future steps with the teslexivir program. In the meantime, we will continue to focus on the advancement of our oral vaccine platform through the clinic.”

Under the leadership of new CMO David Taylor, Vaxart is marching onward with its signature oral vaccines intended to replace the injectables in use. It had a positive Phase II readout in January for its prophylactic influenza pill, and is hoping to do the same with a norovirus program.

The best place to read Endpoints News? In your inbox.

Comprehensive daily news report for those who discover, develop, and market drugs. Join 47,900+ biopharma pros who read Endpoints News by email every day.

Free Subscription

Research Scientist - Immunology
Recursion Pharmaceuticals Salt Lake City, UT
Director of Operations
Atlas Venture Cambridge, MA

Visit Endpoints Careers ->