The purpose of the study is to evaluate the effect of a single, acute dose of BNC210 compared to placebo on reducing the severity of anxiety provoked by a behavioral assessment task and measured using the Subjective Units of Distress Scale (SUDS) in adult patients with social anxiety disorder.

This is a randomized, double-blind, placebo-controlled, 2-arm, parallel-group, multi-center study. Participants will attend a Screening Visit to confirm eligibility and then return to the clinic within 21 days to be randomized into the study. Randomized participants will receive a single dose of their allocated study medication (225 mg BNC210 or placebo) and approximately 1 hour later participate in a behavioral assessment task. After 1 week, a safety follow-up assessment will be conducted by phone/video conference.

Inclusion Criteria:

• A current diagnosis of social anxiety disorder as defined in the DSM-5.
• A Liebowitz Social Anxiety Scale total score of ≥60.
• Suitable contraception use in line with protocol requirements.
• Ability to swallow tablets.

Exclusion Criteria:

• History of bipolar disorder, schizophrenia, schizoaffective disorder, psychotic disorders, anorexia or bulimia, body dysmorphic disorder, PTSD, autism-spectrum disorder or obsessive-compulsive disorder, or any other Axis I or II disorder which is currently the primary focus of treatment over social anxiety disorder.
• Hamilton Rating Scale for Depression score of ≥18.
• Moderate or severe alcohol-use disorder, or any other substance-use disorder (any severity) in the past 12 months.
• Use of psychotropic medications within 30 days of screening. Daily use of benzodiazepines within 90 days of screening.
• 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.