Background: There are no medications approved for as-needed use for feared situations for individuals with social anxiety disorder (SAD). In the present study, intranasal PH94B was provided for use as needed during stressful events.
Methods: Twenty-two subjects were randomized (double-blind) to 2 weeks of treatment with intranasal PH94B or placebo. Following self-administration of medication prior to a feared event, peak levels of anxiety were recorded using the Subjective Units of Distress Scale (SUDS). After 2 weeks, subjects were crossed over to the opposite treatment for 2 weeks. Average peak SUDS during treatment with PH94B and placebo were compared using a paired t-test.
Results: Significant differences in favor of PH94B were found on the primary outcome measure: mean peak SUDS change from baseline for all subjects receiving PH94B was 15.6 points versus 8.3 points for placebo (paired t = 3.09, P = .006, effect size of .658). PH94B showed less superiority over placebo when placebo was given second rather than first, likely due to a carryover effect. Looking between groups at just the first 2 weeks of treatment, PH94B also showed trend superiority to placebo on the Liebowitz Social Anxiety Scale (LSAS) (P = .07) and a significant difference on the Patient Global Impression of Change (P = .024) and the LSAS Avoidance subtotal (P = .02).
Conclusions: While further study is needed, these results, combined with earlier findings, suggest that PH94B could represent a useful as-needed treatment for SAD, and continue to validate the nasal chemosensory system as a novel mechanism for medication delivery.
Trial registration: ClinicalTrials.gov NCT02622958.
Keywords: SAD/social anxiety disorder/social phobia; anxiety/anxiety disorders; pharmacotherapy; phobia/phobic disorders; treatment.
© 2016 Wiley Periodicals, Inc.