SK Biopharmaceuticals(326030) has picked the epilepsy drug candidate "opacalim (BHV-7000)" as its next growth engine, and executives are buying company shares one after another. The moves are seen as an effort to reduce reliance on "Xcopri" and secure a follow-up growth driver.
SK Biopharmaceuticals said on the 31st that Chief Executive Lee Dong-hoon bought 2,000 of the company's shares on the 27th at an average of 90,899 won per share. The total purchase amount is about 1.8 billion won.
The purchase came a day after SK Biopharmaceuticals disclosed the in-licensing of opacalim. Yoo Chang-ho, head of strategy who led the opacalim in-licensing, also bought 500 company shares after the main terms of the related agreement were made public.
SK Biopharmaceuticals said on the 26th that it signed an opacalim in-licensing deal worth up to $795 million (about 1.0995 trillion won) with U.S. biotech company Biohaven. The upfront payment is about $400 million.
Opacalim is a once-daily oral therapeutic candidate that selectively activates the Kv7.2 and Kv7.3 potassium channels, which regulate signal transmission in brain neurons. Phase 2/3 "RISE-2" and "RISE-3" trials are under way in adults with focal-onset seizures. If the trials and approval process proceed as planned, the target is a U.S. launch as early as 2029.
The in-licensing is seen as a card that can ease SK Biopharmaceuticals' concern over relying on a "Xcopri-only" strategy. Rather than pushing to expand into new disease areas, the strategy is to secure a second product in epilepsy, where the company already has a sales base. If opacalim is approved, a strength is that it can leverage the U.S. sales and marketing infrastructure built through Xcopri.
The key is how much opacalim proves actual seizure-suppressing efficacy and tolerability in clinical trials.
Uncertainty over the Kv7 mechanism itself has eased as "azetucalner," a competing Kv7-class investigational drug from U.S. company Xenon Pharmaceuticals, showed efficacy in a phase 3 trial. Accordingly, opacalim needs to demonstrate competitiveness in real-world therapeutic effect and safety rather than novelty of mechanism.
Epilepsy treatments are often taken long term, making tolerability important. The crux is how much it can reduce central nervous system (CNS) side effects such as dizziness and fatigue while securing seizure-suppressing efficacy.
Data disclosed so far are positive. In the open-label extension (OLE), 54% of patients given 75 mg of opacalim saw seizure frequency decrease by at least 50% for six consecutive months. CNS-related side effects were observed at relatively low levels.
However, the OLE has no placebo control group. It is still early to judge that it outperforms competing drugs. Ultimately, efficacy and tolerability must be confirmed in randomized, double-blind, placebo-controlled trials (RCTs).
The first watershed will be RISE-3, with results expected in the second half of this year. It compares 50 mg and 75 mg of opacalim with placebo.
Opacalim previously failed to meet the primary endpoint in a phase 2 trial for major depressive disorder (MDD) and did not succeed in a late-stage trial for bipolar disorder. While disease areas, trial designs and endpoints differ, making it hard to judge the epilepsy trial's outcome based on those results alone, they remain reference points.
If the expected efficacy or safety is not demonstrated in trials, the burden on SK Biopharmaceuticals, which paid a large upfront, will inevitably grow.