Based on results from the phase II TITAN trial of caplacizumab treatment for patients with acquired thrombotic thrombocytopenic purpura (aTTP), the drug’s manufacturers have submitted a Marketing Authorisation Application (MAA) to the European Medicines Agency for approval. If approved, caplacizumab, (a first-in-class anti-von Willebrand factor [vWF] nanobody), would be the first available, on-label drug alternative to plasma exchange therapy for patients with aTTP.
The TITAN trial included 75 patients with aTTP who were randomized 1:1 to receive:
- caplacizumab plus standard of care (plasma exchange; n=36)
- placebo plus standard of care (n=39)
The study showed that caplacizumab reduced the time to platelet count normalization by approximately 40 percent and reduced TTP recurrences by 71 percent.
Overall, 11.4 percent of patients treated with caplacizumab and 43.2 percent of patients treated with placebo experienced ≥1 thromboembolic events or died (p=0.006). Two deaths related to TTP occurred in the placebo group (1 related to refractory TTP and 1 to cerebral hemorrhage), while no patients died in the caplacizumab cohort.
The phase III HERCULES trial of caplacizumab is ongoing, with results expected later this year.
The drug’s manufacturer, Ablynx, said it is targeting a possible launch for the first half of 2018, with a U.S. filing expected around the same time.
Source: Ablynx press release, February 6, 2017.