Real-world data confirm the effectiveness of caplacizumab in acquired thrombotic thrombocytopenic purpura

TLDR

Acquired thrombotic thrombocytopenic purpura is a rare, life‑threatening disorder, and in 2018 the nanobody caplacizumab was approved for adults with an acute episode in combination with plasma exchange and at least 30 days of post‑PEX immunosuppression. The authors recommend administering caplacizumab immediately to all acute aTTP patients, with plasma‑exchange decisions guided by clinical severity and risk factors, and note that plasma‑exchange may be omitted in selected cases. They conducted a retrospective, observational study of 60 patients from 29 German centers to evaluate caplacizumab use during acute disease management. Caplacizumab rapidly normalized platelet counts (median 3 days), was effective regardless of timing or adjunctive therapy, allowed plasma‑exchange‑free regimens in several patients, and only one death occurred after delayed initiation.

Abstract

Acquired thrombotic thrombocytopenic purpura (aTTP) is a rare but life-threatening condition. In 2018, the nanobody caplacizumab was approved for the treatment of adults experiencing an acute episode of aTTP, in conjunction with plasma exchange (PEX) and immunosuppression for a minimum of 30 days after stopping daily PEX. We performed a retrospective, observational analysis on the use of caplacizumab in 60 patients from 29 medical centers in Germany during acute disease management. Caplacizumab led to a rapid normalization of the platelet count (median, 3 days; mean 3.78 days). One patient died after late treatment initiation due to aTTP-associated complications. In 2 patients with initial disease presentation and in 4 additional patients with laboratory signs of an exacerbation or relapse after the initial therapy, PEX-free treatment regimens could be established with overall favorable outcome. Caplacizumab is efficacious in the treatment of aTTP independent of timing and ancillary treatment modalities. Based on this real-world experience and published literature, we propose to administer caplacizumab immediately to all patients with an acute episode of aTTP. Treatment decisions regarding the use of PEX should be based on the severity of the clinical presentation and known risk factors. PEX might be dispensable in some patients.