Deramciclane in the treatment of generalized anxiety disorder: A placebo-controlled, double-blind, dose-finding study

Abstract Deramciclane, a camphor derivative, is a novel anxiolytic agent with a unique mechanism of action. It acts as a potent and specific antagonist at serotonin 5-HT 2A/2C receptors, and exhibits anxiolytic efficacy in animal models. The aim of this double-blind, placebo-controlled, parallel-group study was to evaluate the efficacy, safety, and tolerability of a range of doses of deramciclane in patients with generalized anxiety disorder (GAD). Adult patients with a diagnosis of GAD (DSM-IV) and a Hamilton Anxiety Rating Scale (HAM-A) total score ≥ 18; a score ≥ 2 for the HAM-A items ‘Anxious Mood’ and ‘Tension’; a score ≥ 4 on the Clinical Global Impression of Severity of Illness (CGI-S) Scale; and a score ≤ 20 on the Montgomery–Asberg Depression Rating Scale (MADRS) were enrolled in the study. Following a 1–2 week placebo run-in period, patients were randomized to receive deramciclane (10, 30, or 60 mg/day in two divided doses) or placebo for 8 weeks, followed by a 2-week placebo wash-out period. The primary efficacy measure was change in HAM-A score from baseline to week 8. Adverse events were monitored throughout the study. Withdrawal reactions were assessed at the end of the study (week 8) and during the placebo wash-out period using the Physician's Withdrawal Checklist (34 items). In the intent-to-treat population ( n  = 208), both the deramciclane 30 mg/day and 60 mg/day doses provided clinically relevant improvements in HAM-A total score after 8 weeks of treatment, reaching statistical significance compared with placebo in the 60 mg/day dose group ( p  = 0.024) and a clear trend in the 30 mg/day group ( p  = 0.059). On the HAM-A psychic anxiety factor, significant improvements were seen in patients in the deramciclane 30 mg/day and 60 mg/day treatment groups compared with those in the placebo group ( p