FDA Approves First Therapy for Acquired Thrombotic Thrombocytopenic Purpura in Adults

The FDA has approved caplacizumab-yhdp (Cablivi; Ablynx) for use in combination with plasma exchange and immunosuppressive therapy to treat adults with acquired thrombotic thrombocytopenic purpura (aTTP).

Caplacizumab-yhdp is the first therapy specifically indicated for patients with this rare and life-threatening disorder, was granted Orphan Drug designation by the FDA, and approved through the administration’s Priority Review process.

“Patients with aTTP endure hours of treatment with daily plasma exchange, which requires being attached to a machine that takes blood out of the body and mixes it with donated plasma and then returns it to the body. Even after days or weeks of this treatment, as well as taking drugs that suppress the immune system, many patients will have a recurrence of aTTP,” said Richard Pazdur, MD, Director of the FDA’s Oncology Center of Excellence, in a press statement.

“Cablivi is the first targeted treatment that inhibits the formation of blood clots. It provides a new treatment option for patients that may reduce recurrences,” he added.

This approval was based on the results of a clinical trial evaluating the efficacy of caplacizumab-yhdp in 145 patients who were randomized to receive the current standard of care of plasma exchange and immunosuppressive therapy plus caplacizumab-yhdp or placebo. Findings showed that platelet counts improved faster in patients who received caplacizumab-yhdp than in those who received placebo.

In addition, fewer patients in the caplacizumab-yhdp arm had aTTP-related death or aTTP recurrence during the treatment period than those in the placebo arm. Patients were also less likely to have at least 1 treatment-emergent major thrombotic event if they received caplacizumab-yhdp versus placebo.

Of note, the percentage of patients who had aTTP recurrence during the overall study period was lower with caplacizumab-yhdp than with placebo, a finding the investigators deemed as statistically significant (13% vs 38%, respectively).

Bleeding of the nose or gums and headache were side effects of caplacizumab-yhdp frequently reported in clinical trials of the drug.—Hina Khaliq

Source: US Food and Drug Administration. FDA approves first therapy for the treatment of adult patients with a rare blood clotting disorder. February 6, 2019. https://www.fda.gov/NewsEvents/Newsroom/PressAnnouncements/ucm630851.htm. Accessed February 6, 2019.