PH94B for Social Anxiety Disorder (SAD)

Social anxiety disorder (SAD) affects approximately 15 million American adults and is the second most commonly diagnosed anxiety disorder. 1 SAD is characterized by excessive fear and avoidance of everyday social or performance situations in which individuals feel scrutinized or evaluated by others and fear embarrassment, humiliation and rejection. SAD can significantly compromise academic, social, and work life and can predispose individuals to other anxiety disorders, depression, and substance use disorders.2 

There are no FDA-approved medications for on-demand, as-needed (PRN) treatment of SAD. While three antidepressants (two SSRIs and one SNRI) are FDA-approved for treatment of SAD, they take many weeks to work, if they work at all, must be taken chronically, and often present troubling side effects. Individuals affected by SAD need novel treatment alternatives with fast onset therapeutic benefits and far fewer side effects.

VistaGen’s PH94B neuroactive nasal spray is fundamentally different from all current treatments for SAD. Developed from proprietary compounds called pherines and administered as an odorless nasal spray, PH94B activates nasal chemosensory receptors that trigger neural circuits in the brain that suppress fear and anxiety. Specifically, PH94B engages nasal chemosensory receptors that trigger a subset of neurons in the main olfactory bulbs (OB).  OB neurons then stimulate inhibitory GABAergic neurons in the limbic amygdala, releasing anxiolytic neuropeptide S, decreasing release of norepinephrine, and facilitating fear extinction activity of the limbic-hypothalamic parasympathetic system. Its novel mechanism of pharmacological action, rapid-onset of therapeutic effects and exceptional safety and tolerability profile shown in clinical trials to date make PH94B neuroactive nasal spray an excellent product candidate with potential to become the first FDA-approved PRN treatment for SAD.

In a published randomized, double-blind, placebo-controlled Phase 2 clinical trial, which included both a public speaking and a social situation challenge, PH94B significantly improved the primary efficacy endpoint within 10 to 15 minutes of self-administration.3

In a 22-patient, four-week, randomized, double blind, placebo-controlled pilot Phase 3 crossover study, subjects receiving PH94B had a significantly greater decrease in average peak Subjective Units of Distress scores compared to placebo within one week of treatment. 4 There was also a significantly greater decrease in Liebowitz Social Anxiety Scale (LSAS) avoidance scores for subjects who received PH94B first, before crossing over to placebo. These data were presented in a poster session at the 2019 Anxiety and Depression Association of America (ADAA) Annual Conference.

In all clinical studies to date, PH94B was administered intranasally at microgram doses and without systemic exposure; PH94B's safety profile was excellent, with no serious adverse events. 

VistaGen is currently preparing for pivotal Phase 3 development of PH94B as a novel first-line PRN treatment for SAD.

Learn more about SAD from the U.S. National Institute of Mental Health here.

  2. American Psychiatric Association. (2013). Diagnostic and statistical manual of mental disorders (5th ed.). Arlington, VA: American Psychiatric Publishing.
  3. Liebowitz, MR, Salman, E, Nicolini, H, Rosenthal, N, Hanover, R, Monti. L (2014). Effect of an acute intranasal aerosol dose of PH94B on social and performance anxiety in women with social anxiety disorder. Am. J. Psychiatry 171:675-682.
  4. Liebowitz MR, Hanover R, Draine A, Lemming R, Careri J, Monti L (2016). Effect of as‐needed use of intranasal PH94B on social and performance anxiety in individuals with social anxiety disorder. Depress Anxiety 33: 1081-1089.