Biohaven (BHVN) Cashes In On Its Biggest Epilepsy Bet

On August 26, Biohaven (NYSE:BHVN) and SK Biopharmaceuticals signed a global licensing agreement for opakalim, Biohaven's lead epilepsy candidate, worth up to $795 million plus royalties. Under the deal, SK Biopharmaceuticals gains exclusive worldwide rights to Biohaven's Kv7 ion channel platform, while Biohaven receives $400 million in immediate cash.

The timing coincides with a 2026 earnings report showing Biohaven still experiencing substantial quarterly losses. SK Biopharmaceuticals will pay up to $795 million in upfront and milestone payments, along with royalties on US net sales of opakalim. Biohaven will receive $350 million at closing and an additional $50 million in 2027, with up to $150 million more potential through development milestones and royalties on global sales.

SK Biopharmaceuticals also assumes Kv7 program costs, including obligations from Knopp Biosciences. CEO Vlad Coric emphasized the deal as proof that Biohaven can monetize its pipeline through partnerships. Opakalim showed promising results in a proof-of-concept study for idiopathic generalized epilepsy, reducing the time to a second generalized tonic-clonic seizure by 94 days compared to placebo, and 54% of patients in an extension study experienced a 50% reduction in seizure frequency over six months.

The partnership between Biohaven and SK Biopharmaceuticals, known for its focal-seizure drug XCOPRI, provides a commercial path for opakalim that Biohaven could not build alone. However, Biohaven is surrendering full ownership of an asset that could potentially be a major seller, with royalties of 15-20% of sales being a fraction of the value of outright ownership. The deal also comes with $50 million of the $400 million upfront payment not arriving until 2027.