The U.S. Food and Drug Administration approved Adzynma, the recombinant (genetically engineered) protein product indicated for prophylactic (preventive) or on demand enzyme replacement therapy (ERT) in adult and pediatric patients with congenital thrombotic thrombocytopenic purpura (cTTP), a rare and life-threatening blood clotting disorder.
Adzynma is a purified recombinant form of the ADAMTS13 enzyme that works by providing a replacement for the low levels of the deficient enzyme in patients with cTTP. For prophylactic ERT, Adyznma is administered to help reduce the risk of disease symptoms. The product may also be administered as an on-demand ERT for treatment when the patient is experiencing an acute event. Adzynma is administered intravenously once every other week for prophylactic ERT, and once daily for on-demand ERT.
The safety and effectiveness of Adzynma were demonstrated in a global study evaluating prophylactic and on-demand ERT with Adzynma compared to plasma-based therapies in patients with cTTP.
The efficacy of Adzynma in the prophylactic treatment of patients with cTTP was evaluated in 46 patients who were randomized to receive 6 months of treatment with either Adzynma or plasma-based therapies (Period 1), then crossed over to the other treatment for 6 months (Period 2). The efficacy was demonstrated based on the incidence of thrombotic thrombocytopenic purpura (TTP) events, and TTP manifestations, as well as the incidence of the need for supplemental doses.
The efficacy of on demand ERT was evaluated based on the proportion of acute TTP events responding to Adzynma in both the prophylactic and the on-demand cohorts throughout the duration of the study. All acute and subacute TTP events resolved after treatment with either Adzynma or plasma-based therapies.
The most common side effects associated with Adzynma include headache, diarrhea, migraine, abdominal pain, nausea, upper respiratory tract infection, dizziness and vomiting. During the clinical studies, no adverse events, including allergic reactions, were observed during the administration of Adzynma.
The application was awarded a Rare Pediatric Disease Priority Review Voucher, and granted Priority Review, Fast Track and Orphan designations.