Anavex provides update on Rett Syndrome Program

Anavex Life Sciences reported topline results from the randomized, double-blind, placebo-controlled, Phase 2/3 EXCELLENCE clinical trial, which evaluated the clinical efficacy, safety, and tolerability of 30 mg ANAVEX2-73 in 92 pediatric patients with Rett syndrome between the ages of 5 through 17 years. This was the very first study of ANAVEX2-73 in pediatric patients with Rett syndrome. After 12 weeks, the study showed improvement on the key co-primary endpoint Rett Syndrome Behaviour Questionnaire, which is a detailed 45-item questionnaire for assessing multiple Rett syndrome characteristics by the patients’ caregivers. The other co-primary endpoint, the Clinical Global Impression – Improvement scale, which represents a less granular assessment by the site investigators using a seven-point scoring, was not met. In an ad-hoc analysis, using the predefined mixed-effect model for repeated measure method, after 12 weeks of treatment, ANAVEX2-73-treated patients improved LS Mean -12.93 points on their RSBQ total score compared to LS Mean -8.32 points in placebo-treated patients. The LS Mean difference of -4.65 points between treated and placebo groups was statistically significant. When looking at other placebo-controlled Rett syndrome trials, ANAVEX2-73 compares favorably in terms of absolute RSBQ improvements, with the caveat that cross trials comparisons have their limitations. The key secondary endpoint, the Anxiety, Depression, and Mood Scale, trended favorably. In the same analysis, scores for all RSBQ and ADAMS subscales improved over the course of the study. Collectively, the RSBQ and ADAMS demonstrated improvements in multiple areas, impacting positively in particular repetitive movements, nighttime disruptive behaviors and social avoidance. In the EXCELLENCE study, a large placebo effect was observed which may have masked the compound’s therapeutic effect. Anavex believes to have identified the probable causes. A preliminary review of the safety results indicates there were no new safety signals in the EXCELLENCE study, reinforcing the favorable and manageable safety profile observed with ANAVEX2-73 to date. The most common treatment-related adverse events in the drug-treated group were somnolence and lethargy and were predominantly mild to moderate in severity. There were no clinically meaningful changes observed in SAEs associated with known risks of ANAVEX2-73. Over 91% of patients completing the trial continued into a 48-week open-label extension study, which is ongoing.