Biohaven Ltd. and SK Biopharmaceuticals Co., Ltd. have announced a strategic global licensing and collaboration agreement under which SK Biopharmaceuticals will obtain an exclusive worldwide license to Biohaven’s Kv7 ion channel platform, led by opakalim (BHV-7000), a next-generation, selective Kv7.2/7.3 potassium channel activator currently in Phase 2/3 development for focal epilepsy. The announcement was made on August 26, 2026, from New Haven, Connecticut and Seoul, South Korea.
The agreement positions opakalim for an established global development and commercialization pathway, combining Biohaven’s innovative science with SK Biopharmaceuticals’ proven track record in bringing antiseizure medicines to patients worldwide.
Deal Structure and Financial Terms
Under the terms of the agreement, SK Biopharmaceuticals will make upfront and milestone payments totaling up to $795 million related to the Kv7 platform deal, along with tiered royalties to Biohaven ranging from the mid-teens to the low twenties on U.S. net sales of opakalim.
Biohaven will receive $400 million in near-term cash consideration, structured as $350 million payable at closing and an additional $50 million payable in 2027. Beyond the upfront payments, Biohaven is eligible to receive a further $150 million in development and regulatory milestone payments, in addition to royalties on global net sales of opakalim.
On ex-U.S. net sales, Biohaven will receive a mid-single digit royalty. As part of the transaction, SK Biopharmaceuticals will also assume responsibility for Kv7 program costs going forward, including certain specified Knopp Biosciences and future Kv7 milestone obligations totaling $245 million, comprising up to $185 million payable to Knopp Biosciences upon U.S. and EU approval and a mid-single digit worldwide royalty to Knopp Biosciences, plus up to $60 million in additional milestones related to future Kv7 pipeline programs..
About Opakalim and the Kv7 Platform
Opakalim is the lead asset in Biohaven’s Kv7 platform. As a next-generation, selective Kv7.2/7.3 potassium channel activator, it targets a clinically validated mechanism of action for the treatment of epilepsy. It is differentiated from both first- and second-generation Kv7 activators by its high selectivity for the Kv7.2/7.3 heteromeric channels — the predominant regulators of neuronal excitability — with substantially less activity at GABA receptors. This selectivity profile is hypothesized to contribute to the compound’s favorable tolerability, including low rates of somnolence, dizziness, and fatigue observed in clinical studies to date.
Opakalim is designed to offer a once-daily oral treatment without the need for titration and with a low incidence of burdensome CNS side effects. It has been studied in more than 1,200 participants across multiple clinical trials.
Biohaven is currently conducting two Phase 2/3 randomized, double-blind, placebo-controlled studies evaluating opakalim versus placebo as adjunctive therapy for refractory focal onset epilepsy, along with an open-label extension study assessing long-term efficacy and safety. Topline results from the RISE3 trial are expected in the second half of 2026.
Leadership Perspectives on the Partnership
Vlad Coric, M.D., Chairman and Chief Executive Officer of Biohaven, stated, “This is a landmark partnership that has the potential to deliver a novel treatment for millions of patients with epilepsy who still need better seizure control without exacerbating CNS adverse effects. Opakalim is one of the most exciting assets we have advanced; a selective Kv7.2/7.3 activator designed to deliver meaningful efficacy without the burdensome central nervous system side effects, including sedation and dizziness, associated with so many antiseizure medicines. SK Biopharmaceuticals is an ideal partner having launched XCOPRI and is the only company to bring a new antiseizure medicine for partial-onset (focal) seizures to patients in the U.S. since 2016. Pairing our scientific innovation with SK Biopharmaceuticals’ established epilepsy development and commercialization expertise gives opakalim, if approved, its fastest and strongest path to patients worldwide. This partnership also brings $400 million in near-term, non-dilutive capital to Biohaven while preserving substantial long-term upside for our shareholders.”
Dr. Coric further added, “Beyond opakalim, this transaction validates Biohaven’s strategy of building differentiated, novel platforms that create value for patients and investors while pursuing monetization pathways beyond typical public-market equity raises. With such a robust pipeline, Biohaven has the potential to create value in numerous ways, including an outright sale, license agreements and partnerships with companies looking to expand their clinical-stage pipelines. Rather than stand up a commercial organization of our own for opakalim, we structured a partnership with a leading strategic partner in epilepsy to drive long-term revenue potential of this novel mechanism. This structure allows Biohaven to receive an upfront payment for our development efforts while sharing in future upside of opakalim through milestones and royalties. A strengthened balance sheet, coupled with a meaningfully lower go-forward burn and a world-class partner, lets us sharpen our focus and invest in the next wave of Biohaven innovation, from our MoDE and TRAP extracellular protein degraders in immunology to our programs in neuroscience, metabolic conditions, and rare diseases. We are building a diversified, self-sustaining engine for long-term value creation.”
Donghoon Lee, President and Chief Executive Officer of SK Biopharmaceuticals, commented, “Our experience building XCOPRI into a therapy for epilepsy patients worldwide, from clinical development through global commercialization, has given us a deep understanding of what it takes to bring a differentiated CNS medicine to patients. We see opakalim as a highly complementary addition to our epilepsy portfolio, with a mechanism and tolerability profile that could extend our ability to serve patients who may benefit from additional treatment options. We look forward to a close, collaborative partnership with the Biohaven team through NDA submission and beyond.”
SK Biopharmaceuticals’ Epilepsy Commercial Footprint
SK Biopharmaceuticals brings more than 30 years of history to this collaboration and is recognized as the first global biopharmaceutical company in more than a decade, and the first Korean company, to independently discover, develop, and commercialize a novel antiseizure medicine. Through its U.S. subsidiary SK Life Science, Inc., the company markets XCOPRI® (cenobamate) for partial-onset (focal) seizures in adults in the United States, where it has established a dedicated epilepsy commercial organization with a purpose-built neurology field force of over 150 professionals and strong epilepsy-center and neurologist coverage.
This mature commercial infrastructure, paired with SK Biopharmaceuticals’ global development, regulatory, and commercialization capabilities, has driven the steady, double-digit growth of XCOPRI and expanded patient reach worldwide. The Kv7 platform deal gives opakalim direct access to this proven platform without Biohaven needing to build its own capital-intensive commercial infrastructure.
Transaction Closing Conditions and Advisors
The closing of the licensing and collaboration agreement is contingent on the completion of review under applicable regulatory and antitrust laws, including the Hart-Scott-Rodino (HSR) Antitrust Improvements Act of 1976 in the U.S., along with other customary closing conditions.
J.P. Morgan Securities LLC is serving as exclusive financial advisor and Sullivan & Cromwell LLP is serving as legal advisor to Biohaven. Nomura Securities International, Inc. is serving as exclusive financial advisor and Paul Hastings LLP is serving as legal counsel to SK Biopharmaceuticals.
