Acadia Pharma Jumps After Rett Syndrome Candidate Aces Phase 3 Study

Acadia Pharmaceuticals Inc ACAD announced topline results from Phase 3 Lavender study of trofinetide in Rett syndrome.

• The 12-week study demonstrated a statistically significant improvement over placebo for both co-primary endpoints. 
• Rett syndrome is a rare genetic neurological and developmental disorder that typically affects girls. 
• The Rett Syndrome Behaviour Questionnaire (RSBQ) change from baseline to week 12 was -5.1 vs. -1.7 (p=0.0175; effect size=0.37). 
• The Clinical Global Impression–Improvement (CGI-I) score at week 12 was 3.5 vs. 3.8 (p=0.0030; effect size=0.47). 
• The RSBQ is a caregiver assessment of the core symptoms, and the CGI-I is a global physician assessment of worsening or improving of Rett syndrome.
• Additionally, trofinetide demonstrated a statistically significant separation over placebo on the scale of communication delay. The change from baseline to week 12 was -0.1 vs. -1.1 (p=0.0064; effect size=0.43).
• Study treatment discontinuation rates related to treatment-emergent adverse events (TEAEs) were 17.2% in the trofinetide group compared to 2.1% in the placebo group. 
• The most common adverse events were diarrhea (80.6% with trofinetide vs. 19.1% with placebo).
• Acadia is preparing for a pre-NDA meeting with the FDA in Q1 of 2022 and plans to submit a marketing application around mid-year 2022. 
• Price Action: ACAD shares are up 14% at $22.12 during the premarket session on the last check Tuesday.