XENE · Xenon Pharmaceuticals Inc.

Summary

Xenon Pharmaceuticals Inc. announced positive topline data from the Phase 3 X-TOLE2 study of azetukalner in focal onset seizures, meeting primary endpoint with -53.2% median percent change in monthly FOS frequency for 25 mg dose (p=0.000000000006) versus -10.4% for placebo, and plans NDA submission to FDA in Q3 2026.

Key takeaways

• X-TOLE2 met primary endpoint: -53.2% MPC (25 mg), -34.5% MPC (15 mg), -10.4% placebo (p<0.0001)
• Placebo-adjusted MPC -42.7% (25 mg) outperformed Phase 2b X-TOLE (-34.6%)
• RR50: 54.8% (25 mg), 37.6% (15 mg), 20.8% placebo (p<0.01)
• Safety profile consistent with X-TOLE; dizziness 20.5% (azetukalner) vs 3.2% placebo
• NDA submission to FDA planned Q3 2026 for FOS
• 380 participants randomized; median 5 prior ASMs, baseline 12.75 FOS/month