Vistagen Receives FDA 'Study May Proceed' Letter

Vistagen announced receipt of a "Study May Proceed" letter from the U.S. Food and Drug Administration under its U.S. Investigational New Drug application for refisolone nasal spray, the Company's non-hormonal, non-systemic product candidate in Phase 2 development for treatment of moderate to severe vasomotor symptoms due to menopause. The FDA's Study May Proceed letter enables the Company to pursue further Phase 2 clinical development of refisolone in the U.S. for a large unmet need in women's health, building on successful exploratory Phase 2a clinical studies for the treatment of menopausal hot flashes and premenstrual dysphoric disorder conducted in Mexico. In an exploratory randomized, double-blind, placebo-controlled Phase 2a clinical study in VMS due to menopause in menopausal women with eight or more daily hot flashes, refisolone was administered intranasally at a 3.2 undefined dose as needed up to five times daily for four weeks. Refisolone demonstrated statistically significant improvements versus placebo in both the frequency and severity of daily menopausal hot flashes, with hot flash frequency reduced by 80% in refisolone-treated patients compared to 36% in the placebo group. The reduction in the frequency of hot flashes was observed as early as one week in the refisolone population. Refisolone was well-tolerated in the study, with no serious drug-related adverse events. The exploratory Phase 2a study was conducted in Mexico by Pherin Pharmaceuticals, now a wholly owned subsidiary of Vistagen.