FDA Grants Orphan Drug Status to AB Science’s Masitinib Drug For ALS

Pharmaceutical company AB Science SA received orphan drug designation from the U.S. Food and Drug Administration (FDA) for its investigational therapy for amyotrophic lateral sclerosis (ALS), called masitinib. The drug is a protein kinase inhibitor (PKI) and was granted the status in order to accelerate its development and address a rare condition with severely unmet needs.

Masitinib was selected to receive the orphan drug designation based on applications reviewed by the Office of Orphan Drug Products Development at the FDA. The status is granted to promising medications focused on treating a condition that affects less than 200,000 patients in the U.S.

AB Science will be granted seven years of marketing exclusivity in the country after regulatory approval due to the designation, and may now qualify for a series of research grants to support phase I and II clinical trials, tax and fee reductions, and FDA support during the regulatory process. The FDA noted, however, that it does not change the need for fulfillment of the standard regulations regarding the safety and efficacy of the drug.

Masitinib is an orally administered therapy that works by targeting the mast cells and macrophages, which are crucial for the immune system, and by inhibiting a determined amount of kinases. It has a unique mechanism of action and is expected to improve the quality of life of patients with inflammatory diseases, as well as conditions of the central nervous system, by reducing both the burden of the symptoms and the progression of the disease.

AB Science is currently evaluating masitinib for the treatment of ALS in a phase 3 multicentered, double-blinded, randomized and international study. With the main purpose of assessing the safety and efficacy of the drug, it is given to patients that have been treated previously with a known and stable dose of riluzole. Researchers measured the efficacy of the compound after 48 weeks of treatment, using the Amyotrophic Lateral Sclerosis Functional Rating Scale (ALSFRS-Revised).

In addition, the external Data and Safety Monitoring Board (DSMB) recommended the company’s phase 3 study of masitinib in ALS be continued, which was supported by the drug’s latest safety reports. The DSMB was established as part of the AB Science’s clinical study to assess masitinib.