Ab Science’s Potential Treatment for ALS, Masitinib, Named an Orphan Drug by EMA

AB Science announced that the European Medicines Agency’s (EMA) Committee for Orphan Medicinal Products (COMP) has granted Orphan Drug status to masitinib, a potential treatment for amyotrophic lateral sclerosis (ALS).

Masitinib is an orally administered tyrosine kinase inhibitor targeting mast cells and macrophages, key immune system cells, that works to prevent activation of the inflammatory process though its inhibitory actions on these cells. As such, it might be effective in treating inflammatory and central nervous system (CNS) diseases like ALS.

In a press release, AB Science said it considered COMP’s designation a recognition that masitinib in combination with riluzole (available as Rilutek in the U.S.) has demonstrated an ability to be a significant improvement in treatment compared riluzole alone. The decision was based on the results of the interim analysis in its ongoing Phase 2/3 clinical trial (NCT02588677), evaluating the efficacy and safety of masitinib in combination with riluzole in ALS patients.

Masitinib was previously designated an Orphan Drug by the U.S. Food and Drug Administration (FDA) for ALS. The criteria required for this status in Europe can be more stringent, however, and requires:

• where authorized medicinal products already exist, the sponsor provide justification for the assumption that the medicinal product for which the designation is being sought will be significantly better
• where significant is the basis of the application, a comparative study with previously treatments is required
• because orphan drug applications to COMP can be made at any point in development, available evidence must support claims of significant benefit

According an interim analysis in 192 patients released by AB Science earlier this year, reported in ALS News Today,  the trial met its primary outcome, the change from baseline to week 48 in the Amyotrophic Lateral Sclerosis functional rating scale (ALSFRS), a validated rating tool for monitoring disability progression in ALS patients.

“The granting of this orphan drug status is one more positive milestone from EMA after acceptance for the filing for conditional marketing authorization, still planned in September 2016,” Alain Moussy, AB Science’s chief executive officer, said in a press release.