This U.S. multicenter, double-blind, placebo-controlled Phase 2 clinical trial is designed to evaluate the efficacy, safety, and tolerability of a repeat intranasal (i.n.) dose of Fasedienol Nasal Spray (fasedienol) (3.2 µg) to relieve symptoms of acute anxiety in adult subjects ages 18 through 65 with Social Anxiety Disorder induced by a public speaking challenge (PSC) in a clinical setting. In addition, safety and tolerability of i.n. administration of 3.2 µg of fasedienol, as-needed, up to 6 times per day for up to 12 months, will be assessed in those subjects who complete PH94B-CL036 and choose to enter the distinct open-label extension phase of the study.

Inclusion Criteria:

• Written informed consent provided prior to conducting any study-specific assessment.
• Male and female adults, 18 through 65 years of age, inclusive.
• Current diagnosis of SAD as defined in the Diagnostic and Statistical Manual of Mental Disorders, 5th Edition, and confirmed by the Mini-International Neuropsychiatric Interview (MINI).
• Clinician-rated Liebowitz Social Anxiety Score (LSAS) total score ≥70 at Screening (Visit 1).
• Clinician-rated Hamilton Depression Rating Scale (HAM-D) (17-items) total score <16.
• Female subjects of childbearing potential must be able to commit to the consistent and correct use of an effective method of birth control throughout the study
• Subjects must have normal olfactory function

Exclusion Criteria:

• Any history of bipolar disorder (I or II), schizophrenia, schizoaffective disorder, psychosis, anorexia or bulimia, premenstrual dysphoric disorder, autism spectrum disorder, or obsessive-compulsive disorder.
• Any other current principal or personality disorder (previously known as Axis I or Axis II disorders), except for specific phobias or generalized anxiety disorder, provided that these are not the primary diagnosis.
• Subjects who meet criteria for moderate or severe alcohol use disorder within the 1 year prior to study entry, or any use of illicit substances or tetrahydrocannabinol ("THC") within 2 months prior to study entry.
• In the opinion of the investigator, the subject has a significant risk for suicidal behavior during the course of their participation in the study, or the subject is considered to be an imminent danger to themself or others.
• Clinically significant nasal pathology or history of significant nasal trauma, nasal surgery, total anosmia, or nasal septum perforation that may have damaged the nasal chemosensory epithelium.
• Two or more documented failed adequate treatment trials with a registered medication approved for SAD.
• Currently receiving cognitive-behavioral therapy (CBT), exposure therapy, or acceptance and commitment therapy.
• Subjects taking psychotropic medications within 30 days before Visit 2.
• Use of any over-the-counter product, prescription product, off-label treatment, cannabidiol ("CBD"), or herbal preparation for treatment of the symptoms of anxiety or social anxiety within 30 days before Visit 2.
• Prior participation in a clinical trial involving fasedienol.
• Participation in any other clinical trial within the last 30 days or during the course of the current trial.
• Subjects with a positive urine drug screen.
• Women who have a positive urine pregnancy test.
• Women who are currently breastfeeding are not eligible unless they are willing to stop breastfeeding for the duration of the study.
• Subjects who have tested positive and/or have exhibited symptoms consistent with SARS-CoV-2 infection during the 4 weeks prior to Screening (Visit 1).
• Any clinically significant medical history or findings as determined by the Investigator that could interfere with the objectives of the study or put the participant at risk.