AB Science S.A. received authorization from the French National Agency for the Safety of Medicines and Health Products to resume patient enrollment in the confirmatory Phase 3 study of masitinib (AB19001) in amyotrophic lateral sclerosis, and also authorization from the UK (MRHA) and Dutch (CCMO) National Agencies of Medicine in the confirmatory Phase 3 study of masitinib (AB15003) in mastocytosis. These authorizations follow the validation in July 2021 by the ANSM of the measures proposed by AB Science to reinforce patient safety related to cardiac risk in its ongoing studies. These authorizations follow those already received from European agencies, in amyotrophic lateral sclerosis (Norway) and in mastocytosis (France), and confirm a global resumption of these studies.