Biohaven in recent months has reported a clinical stumble in spinal muscular atrophy, alongside a Phase I readout for its protein degrader candidate that investors found underwhelming.
Biohaven on Monday delivered another underwhelming readout, announcing that its potassium channel activator BHV-7000 failed to elicit significant benefit in a Phase II/III bipolar mania study. The announcement came during the company’s fourth-quarter and full-year business report
Without providing specific data, Biohaven revealed that BHV-7000 “did not statistically differentiate from the comparator arm” on the study’s primary endpoint of 21-day improvement in the Young Mania Rating Scale, a validated tool used to measure manic symptoms over time. The study enrolled more than 250 patients with bipolar I disorder who were experiencing manic episodes. BHV-7000 was compared against placebo.
Biohaven is performing additional analyses of the data and promised to present complete data at an upcoming scientific meeting.
BHV-7000 is an investigational oral drug that works by selectively activating the Kv7.2/7.3 potassium channels. This mode of action allows the candidate to modulate pathological hyperexcitability that can play a role in various neuropsychiatric conditions, including mania. Unlike other potassium channel agonists, BHV-7000 elicits only minimal GABAA activation, which is a source of safety concerns for other drugs that treat bipolar mania.
Indeed, in the Phase II/III bipolar mania study, Biohaven touted a “highly favorable and differentiated” safety profile versus other anti-seizure medications. Even at its highest dose of 75 mg once daily, BHV-7000 did not have adverse effects on patients’ vital signs, electrocardiograms and blood laboratory findings, as per the biotech’s news release on Monday.
Despite the underwhelming mania data but buoyed by its encouraging safety and tolerability profile, Biohaven will push through with its ongoing Phase II/III studies of BHV-7000 in major depressive disorder, focal epilepsy and generalized epilepsy. A readout in depression is expected later this year, while data for focal epilepsy are scheduled for the first half of 2026.
As far as clinical performance goes, the last few months have been tough for Biohaven. In November 2024, the company reported a Phase III flop for its myostatin and activin receptor blocker taldefgrobep alfa, which was unable to significantly boost motor function in spinal muscular atrophy. Nevertheless, Biohaven reiterated its confidence in the asset, announcing at the time that it would push through with its Phase II trial in obesity.
A few months earlier, in May 2024, Biohaven also unveiled disappointing Phase I data for its lead protein degrader BHV-1300 for treating antibody-related conditions like rheumatoid arthritis, myasthenia gravis and systemic lupus erythematosus. While results showed a strong and rapid drop in autoantibody IgG concentrations, investors appeared to be underwhelmed, sending the company’s stocks crashing 12.6% in the readout’s aftermath.
