First positive U.S. Phase 3 study of an investigational therapy for social anxiety disorder in over 15 years

Statistically significant rapid-onset reduction in patient-reported Subjective Units of Distress Scale (SUDS) score compared to placebo in a public speaking challenge (primary endpoint, p=0.015)

Trial also met the secondary endpoint, demonstrating a statistically significant difference in proportion of responders compared to placebo as measured by the Clinical Global Impressions Improvement (CGI-I) scale (secondary endpoint, p=0.033)

Fasedienol was well-tolerated and demonstrated a favorable safety profile consistent with all prior trials of fasedienol in social anxiety disorder

Over 25 million Americans are living with social anxiety disorder and 188 million worldwide, including at least 11.3 million in China.^[1,2,3]

AffaMed Therapeutics ("AffaMed") announced today that its partner Vistagen Therapeutics ('Vistagen' - NASDAQ: VTGN), a clinical-stage biopharmaceutical company aiming to transform the treatment landscape for individuals living with anxiety, depression and other central nervous system (CNS) disorders, reported positive top-line results from its Phase 3 PALISADE-2 trial evaluating the efficacy, safety, and tolerability of fasedienol (PH94B) nasal spray in adults diagnosed with social anxiety disorder (SAD). The trial met its primary endpoint, with fasedienol demonstrating a statistically significant difference in average SUDS score during a public speaking challenge compared to placebo (p=0.015). The trial also met its secondary endpoint, demonstrating a statistically significant difference in the proportion of clinician-assessed responders between fasedienol and placebo as measured by the CGI-I scale (p=0.033). Fasedienol was well-tolerated and demonstrated a favorable safety profile consistent with all prior trials.

In June 2020, VistaGen entered into a strategic licensing and collaboration agreement with AffaMed Therapeutics for the clinical development and commercialization of PH94B in China, South Korea, and Southeast Asia.

"We are thrilled that these compelling top-line results from the Phase 3 PALISADE-2 trial confirm what was seen in the Phase 2 studies in social anxiety disorder and highlight the potential for fasedienol, with its novel and unique proposed mechanism of action, to transform what is possible for more than 25 million people living with social anxiety in the U.S. and millions more affected worldwide," stated Shawn Singh, Chief Executive Officer of Vistagen. "As a new class of medicines, our pherine nasal spray pipeline holds the potential to transform the treatment landscape across numerous therapeutic areas. At the head of that class, fasedienol's potential, as demonstrated in this Phase 3 trial, sets the stage for the first fundamentally new class of medicine for individuals living with SAD in more than 20 years."

Dr. Dayao Zhao, Chief Executive Officer of AffaMed commented: "We are extremely pleased to see the results from the PALISADE-2 trial demonstrating the potential for fasedienol in the treatment of social anxiety, and we look forward to working together with Vistagen to bring forward this new treatment option for the rapidly growing number of individuals living with SAD in China, South Korea, and Southeast Asia".

Primary Efficacy Endpoint

The PALISADE-2 trial (n=141) met its primary efficacy endpoint, the difference in mean SUDS score during the public speaking challenge at baseline (Visit 2) and treatment (Visit 3) for patients who received fasedienol (n=70) compared to placebo (n=71) at Visit 3. Fasedienol-treated patients demonstrated a statistically significant greater change in mean SUDS score (least-squares (LS) mean = -13.8) compared to placebo (LS mean = -8.0), for a difference between groups of -5.8 (p=0.015).

Secondary Efficacy Endpoint

The trial met its secondary endpoint, demonstrating a statistically significant difference in the proportion of clinician-assessed responders between fasedienol and placebo as measured by the CGI-I scale. Responders were identified as those who were rated 'very much less anxious' or 'much less anxious' with 37.7% (n=70) of fasedienol-treated patients rated as responders, as compared to 21.4% (n=71) of those treated with placebo (p=0.033).

Exploratory Efficacy Endpoints

The trial met an important exploratory endpoint of the difference in the proportion of patient-assessed responders between fasedienol and placebo as measured by the Patient's Global Impression of Change (PGI-C) scale. Responders were identified as those who self-rated 'very much less anxious' or 'much less anxious' with 40.6% (n=70) of fasedienol-treated patients rated as responders, as compared to 18.6% (n=71) of those treated with placebo (p=0.003).

The trial also met the exploratory endpoint of the difference in the proportion of patients in each treatment group with a 20-point improvement in patient-assessed SUDS score from baseline (Visit 2) to treatment (Visit 3). Of the fasedienol-treated patients, 35.7% (n=70) demonstrated this statistically significant and clinically meaningful improvement in SUDS score, as compared to 18.6% (n=71) in the placebo-treated group (p=0.020).

Safety

Fasedienol was observed to be well-tolerated in the study with no severe or serious adverse events (AEs) reported. All treatment-emergent adverse events reported for the overall study were mild or moderate. There were no AEs reported in the fasedienol treatment arm above 2% occurrence.