As KalVista Pharmaceuticals awaits an FDA decision on its hereditary angioedema (HAE) treatment sebetralstat, the company has sold the Japanese rights to the drug to Kaken Pharmaceutical for $11 million upfront.
Alongside the upfront fee, Tokyo-based Kaken has also agreed a further $11 million payment if a regulatory milestone is hit next year. There are additional commercial milestone payments tied to the deal should sebetralstat get approved in Japan, but KalVista didn’t go into details in its April 8 release.
Royalties tied to the deal would be based on the drug’s price in Japan, with a royalty rate “as a percentage of sales approximately in the mid-twenties,” KalVista explained.
HAE is a genetic disease marked by low levels or dysfunction of the C1 inhibitor. Patients can be struck with bouts of severe swelling across the body, and attacks can be fatal if they impact the lungs.
The FDA is expected to make a call on whether to approve sebetralstat, an oral plasma kallikrein inhibitor, in the U.S. in June as an on-demand treatment for HAE attacks in adult and pediatric patients aged 12 years and older. The application was based on a phase 3 study last year that showed patients who received either a 300-mg or 600-mg dose of sebeltralstat experienced quicker symptom relief by roughly four hours each compared to placebo.
KalVista has also submitted sebetralstat to regulators in Japan. If approved, it would be the first oral on-demand treatment for HAE available in the country, the biotech noted.
Kaken already markets an array of products in Japan, including hyaluronate sodium for osteoarthritis and Fiblast for skin ulcers. The company has also licensed a number of drugs from other companies, including seladelpar for primary biliary cholangitis from CymaBay Therapeutics, tildacerfont from Spruce Biosciences for congenital adrenal hyperplasia and—most recently—Alumis’ late-stage TYK2 inhibitor as a dermatology treatment
“We are pleased to partner with Kaken, whose expertise and demonstrated success in the region make them well-suited to work alongside our exceptional team to bring sebetralstat to the HAE community in Japan,” KalVista CEO Ben Palleiko said in the release.
“This collaboration is an important part of our strategy to expand the global reach of sebetralstat as we prepare for several commercial launches starting this year,” Palleiko added.
Even if sebetralstat gets the nod from the FDA in the June, it may only have a few weeks’ headstart on donidalorsen, Ionis Pharmaceuticals’ RNA-targeted medicine for preventing HAE attacks, which is expecting a decision in August. Meanwhile, CSL secured EU approval for its prophylactic HAE drug garadacimab in February, while Intellia has a CRISPR-based gene editing candidate in development.