SK Biopharmaceuticals Signs Up-to-$795 Million Biohaven Deal for Epilepsy Drug

SK Biopharmaceuticals has agreed to acquire exclusive global rights to Biohaven’s investigational epilepsy drug opakalim (BHV-7000), related Kv7 activators, and the underlying discovery platform.

The agreement is valued at up to $795 million:
$400 million in upfront cash—$350 million at closing and $50 million one year later—plus as much as $395 million in development and regulatory milestones. Royalties on future sales are additional.

Opakalim is a selective Kv7.2/7.3 potassium-channel activator being tested in Phase 2/3 trials for focal-onset epilepsy. Biohaven will continue running the trials, while SK covers development costs.

SK expects initial RISE3 trial results by the end of 2026, another data readout in 2028, and—if clinical and regulatory milestones are met—a U.S. launch as early as 2029 through SK Life Science.

The deal strengthens SK’s neurology portfolio beyond its established epilepsy treatment cenobamate (XCOPRI). Opakalim remains investigational and is not guaranteed to receive regulatory approval.