SK Biopharm's cenobamate completes Northeast Asia rollout with Japan launch

SK Biopharm's epilepsy drug cenobamate has officially launched in Japan, completing the company's commercial rollout across all three Northeast Asian markets — South Korea, China and Japan.

The expansion shifts the company's revenue base, long anchored in the United States and Europe, into Asia's core markets, accelerating its push toward global blockbuster status.

SK Biopharm announced Friday that its Japanese partner, Ono Pharmaceutical, has begun selling cenobamate locally under the brand name Ekiscopuri — roughly two months after Japan's Ministry of Health, Labour and Welfare granted approval for the drug in September.

The Japan launch follows cenobamate's entry into China in March and South Korea earlier this month, rounding out the company's Northeast Asia presence. The drug has now secured regulatory approval in about 50 countries and regions worldwide, building on its established foothold in Western markets to extend its commercial reach across Asia.

Industry observers say the completion of launches across South Korea, China and Japan goes beyond a simple expansion of sales territories and is expected to translate into tangible earnings growth and a stronger global profile for SK Biopharm.

Japan, the world's second-largest single-country epilepsy market, is now poised to become a meaningful revenue contributor. The country is estimated to have about 1 million epilepsy patients and is regarded as a market with high receptivity to new drugs and a stable drug-pricing framework.

SK Biopharm signed a technology licensing agreement with Ono Pharmaceutical in October 2020, and the Japan launch now triggers royalty payments tied to local sales. Combined with direct US sales, royalties from China and domestic revenue in South Korea, the company's regional earnings portfolio is set to become significantly more diversified.

Strong clinical data from trials conducted in East Asian populations also underpins the drug's prospects in the region. In a Phase 3 trial targeting adults with partial-onset seizures in South Korea, China and Japan whose seizures were not adequately controlled by existing anti-seizure medications, the complete seizure-freedom rate over a six-week maintenance period was 12.4 percent in the 100-milligram group, 30.1 percent in the 200-milligram group and 52.4 percent in the 400-milligram group — far exceeding the 2.6 percent recorded in the placebo group. Should medical professionals across the three countries share patient data and accumulate prescribing experience together, cenobamate could establish itself as a standard treatment across Northeast Asia.

"With launches now completed in South Korea, China and Japan, we have built a solid commercial foundation across the major Northeast Asian markets," SK Biopharm President Lee Dong-hoon said. "We will extend the success we have built in the United States to Asia and drive continued growth."