Catalyst Pharmaceuticals has taken the first step to expand its commercial territory to cover Japan and get Firdapse (amifampridine phosphate) approved as a treatment for Lambert-Eaton myasthenic syndrome (LEMS) in the country.
The company announced it has amended the original license agreement of Firdapse, which was signed in October 2012 and only covered North America, to also include Japan.
Supported by this expanded coverage, Catalyst is planning to request orphan drug designation for Firdapse to treat LEMS in Japan. If successful, this new status will provide further regulatory and financial support to ensure that Firdapse will become the first approved therapy for LEMS in Japan.
“The available treatment options for LEMS patients in Japan are very limited and without an approved evidence-based therapy,” Patrick J. McEnany, chairman and CEO of Catalyst, said in a press release. “We are pleased to have expanded the scope of our license to include Japan and possibly other territories, as we believe that Japan represents an attractive strategic opportunity for Catalyst.”
“We look forward to working with the regulatory authorities in Japan to potentially advance Firdapse as a new treatment option for LEMS patients and their families,” he said.
The company also announced that upon the achievement of a certain milestone in Japan, it will have the option to expand its commercial territory further to also include most of Asia and Central and South America countries.
Firdapse was developed to block potassium channels in nerve cells, inducing the opening of slow voltage-dependent calcium channels and an influx of calcium in these cells. The therapy also has the ability to promote the release of more acetylcholine (Ach), a strong signaling molecule of nerve cells that is lacking in LEMS patients.
These biochemical mechanisms promote an increased responsiveness and activity of nerve cells and their communication with muscles.
Result from Phase 3 clinical studies demonstrated that treatment with Firdapse could effectively lead to clinically significant improvements in the outcomes of adult patients and a decrease in LEMS symptoms compared with a non-active placebo.
Firdapse is the only approved medication in Europe for the symptomatic treatment of adults with LEMS, and it was approved in November 2018 for the same indication in the United States.
In related news, Catalyst recently filed a lawsuit against the U.S. Food and Drug Administration and several related parties over the approval of Jacobus Pharmaceutical’s Ruzurgi (amifampridine) for the treatment of children with LEMS.
According to the lawsuit, Ruzurgi’s approval violated some regulations regarding labeling that resulted in misbranding in violation of the Federal Food, Drug, and Cosmetic Act. The lawsuit also alleges that this approval violates Catalyst’s rights to exclusivity for this therapeutic compound.
The company is seeking retraction of the FDA’s approval of Ruzurgi.