AB Science SA announced that it has taken the decision to suspend inclusions and treatment initiation in its clinical studies with masitinib worldwide. This decision follows consultation with the French regulatory authorities (ANSM) and other regulatory agencies. This decision is relevant to three studies: phase 3 in mastocytosis (AB15003), phase 3 in amyotrophic lateral sclerosis (AB19001) and phase 2 in COVID (AB20001). To this end, AB Science has filed or will file without delay a request for a temporary study hold in all countries where these studies are ongoing. AB Science has identified a potential risk of ischemic heart disease with masitinib. This signal was detected in a retrospective analysis of controlled and unblinded studies of masitinib. Following its own internal procedures, AB Science has decided to suspend inclusion in ongoing studies with masitinib until the investigation of this potential safety issue is finished. AB Science is working closely with the ANSM and other regulatory agencies to complete the necessary additional analyses.