Kaken Pharmaceutical is paying $16 million upfront for the Japanese rights to Astria Therapeutics’ phase 3-stage hereditary angioedema (HAE) drug.
Astria took the candidate, a monoclonal antibody inhibitor of plasma kallikrein called navenibart, into a late-stage study off the back of a phase 1b/2 trial last year that tied the drug to up to a 92% reduction in HAE attacks at six months.
In return for the rights to develop and commercialize navenibart in its home territory of Japan, Kaken is handing over $16 million upfront, with potentially another $16 million to follow in commercialization and sales milestones. Astria could also be in line for tiered royalties on net sales and partial reimbursement for its phase 3 costs.
“We are thrilled to partner with Kaken for the development and commercialization of navenibart in Japan, which advances our strategy to enable broad access to navenibart globally,” Astria CEO Jill Milne, Ph.D., said in an August 6 release.
“In addition to our shared values that put patients first, Kaken brings strong relationships with the Japanese medical community that we believe will support both our phase 3 Alpha-Orbit trial as well as the potential commercialization of navenibart in the future,” Milne added.
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.
CSL’s HAE preventative treatment Andembry was approved in Japan earlier this year, before gaining the go-ahead from the FDA in June. It set up CSL to take on Takeda’s blockbuster Takhzyro and BioCryst Pharmaceuticals’ fast-rising Orladeyo in a competitive market to treat patients with the rare genetic condition.
Today’s deal is a good fit for Tokyo-based Kaken, which scooped up the Japan rights to another late-stage HAE asset in April in the form of KalVista Pharmaceuticals’ sebetralstat. The drug was approved by the FDA last month under the brand name Ekterly.
Earlier in the year, Kaken also acquired the Japanese rights to develop Alumis’ late-stage tyrosine kinase 2 (TYK2) inhibitor as a dermatology treatment in Japan.
Kaken already markets a variety 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 and tildacerfont from Spruce Biosciences for congenital adrenal hyperplasia.
“Our partnership with Astria for the development and commercialization of navenibart supports our strategy of providing therapies that address unmet medical needs in the Japanese community,” Kaken’s president, Hiroyuki Horiuchi, said in today’s release.
“We believe that navenibart is a complementary fit with our HAE portfolio, providing patients in Japan with the potential for low-burden treatments to better manage their disease,” Horiuchi added.