The FDA has put enrollment in trials of Biohaven’s epilepsy drug candidate BHV-7000 on hold in response to findings from rodent tests, dealing a blow to an asset covered by a pending $350 million deal.
Biohaven contacted the FDA about metabolites of BHV-7000, also called opakalim, seen in rodent tests. There is too little information to tell what threat the metabolites—a substance generated when the body breaks down the drug—pose to humans, the company said, but the FDA hit the program with a partial clinical hold. The FDA’s action precludes the recruitment of new patients but permits the treatment of participants who have already enrolled in a pair of pivotal studies.
The FDA imposed the hold days after Biohaven agreed to license BHV-7000 to SK Biopharmaceuticals. Late last month, SK agreed to pay Biohaven $350 million upfront, plus another $50 million next year, for the worldwide license to the asset. The deal also features up to $150 million in milestones and makes SK responsible for Biohaven’s obligations to Knopp Biosciences, the drug candidate’s original developer.
All clinical and nonclinical data, including results related to the metabolite characterization submitted to global regulatory authorities, were fully disclosed to SK before the licensing deal was signed, Biohaven said. The business partners will continue working to complete the deal, the company added.
The affected studies are testing BHV-7000, a selective activator of Kv7.2/7.3 potassium channels, in focal epilepsy. Because enrollment in one of the trials is complete, Biohaven continues to expect to report topline data from the study this year.
Enrollment in the second study is paused pending nonclinical data that Biohaven is generating to assess what, if any, risk the metabolites pose to humans. The company expects to have the data in the coming weeks. The nonclinical findings may be specific to rodents and not relevant to the safety of humans.