VistaGen gets green light to restart phase 3 trial for social anxiety spray despite past failure

VistaGen Therapeutics has been given the all-clear to continue a phase 3 trial of its social anxiety nose spray after the biotech paused enrollment following poor results from a similar late-stage study.

After the failure of the spray, called PH94B, in the Palisade-1 trial for social anxiety disorder (SAD), the mental-health-focused company announced last month that in July it had paused enrolment for the Palisade-2 trial.

The company decided to bring in an independent biostatistician for an interim analysis of unblinded data from 140 Palisade-2 participants who had completed the study. VistaGen also said at the time that it would meet with the FDA to consider whether PH94B has a future in social anxiety disorder.

That interim analysis has now been completed, concluding that Palisade-2 should continue as planned, VistaGen said in a press release. The company will resume enrolling the trial up to its originally planned target of 208 patients, with top-line results expected to read out in the first half of 2023.

CEO Shawn Singh said the biotech was encouraged by the recommendation to proceed, adding that the company is preparing to meet with the FDA later in the year to discuss a proposed further phase 3 trial of PH94B in SAD.

Singh previously expressed confidence in the therapy—which VistaGen licensed from Pherin Pharmaceuticals—in a recent earnings report, pointing to preliminary data from an open-label trial where patients used PH94B as needed to address their social anxiety. The therapy is also backed up by phase 2 data showing it can reduce the severity of social anxiety on an acute, as-needed basis and improve everyday functioning, according to Singh.

VistaGen’s shares were trading up 6% at 17 cents apiece in the market’s opening hour Sept. 8. However, this remains a fraction of their September 2021 peak of $3.16.

The company has already reduced certain activities to cut cash burn and reduced other spending for the next year to come. VistaGen also has a second nasal spray called PH10 in phase 2 development for multiple depression disorders.