FDA Approves Enzyme Replacement Therapy for Rare Clotting Disorder

The FDA has approved Takeda’s Adzynma (ADAMTS13, recombinant-krhn) to treat adults and children with congenital thrombotic thrombocytopenic purpura (cTTP).

cTTP is an ultra-rare, chronic blood clotting disorder caused by a deficiency in the ADAMTS13 enzyme. In TTP, blood clots form in small blood vessels, limiting the flow of blood to the brain, kidneys, and heart. When left untreated, acute TTP events have a mortality rate of more than 90%.

Adzynma is a therapy that replaces the deficient ADAMTS13 enzyme. It is expected to be available in December, and a price will be available at that time.

“In recent decades, significant progress has been made to better understand the link between ADAMTS13 deficiency and cTTP, ultimately leading to this moment where we finally have an FDA-approved treatment option for patients living with this rare disease,” Spero R. Cataland, M.D., professor of internal medicine at the Wexner Medical Center at The Ohio State University, co-director at the U.S. Thrombotic Microangiopathy Alliance (USTMA) and Adzynma clinical trial investigator, said in a press release.

The FDA approval was supported by the totality of the evidence provided by the analysis of efficacy, pharmacokinetic, safety and tolerability data from a phase 3 trial that enrolled 37 patients who received the enzyme therapy, as well as by data from the continuation trial. In the phase 3 trial, no patient treated with Adzynma experienced an acute TTP event.

The most common adverse reactions were headache, diarrhea, migraine, abdominal pain, nausea, upper respiratory tract infection, dizziness and vomiting.