According to a late-breaking abstract at the 2017 American Society of Hematology (ASH) Annual Meeting in Atlanta, Georgia, caplacizumab improves outcomes among patients with acquired thrombotic thrombocytopenic purpura (aTTP), including time to resolution, recurrence rates, aTTP-related death rates, and rates of major thromboembolic events during treatment.1
For the double-blind phase 3 HERCULES study (ClinicalTrials.gov Identifier: NCT02553317), investigators randomly assigned 145 patients to receive daily plasma exchange and corticosteroids plus caplacizumab 10 mg or placebo.
Caplacizumab was administered intravenously prior to the first round of plasma exchange and then subcutaneously during each plasma exchange for 30 days thereafter. In the presence of ongoing disease, the study period was extended by 4 weeks with immunosuppression, followed by a 4-week treatment free period.
Compared with patients in the placebo arm, patients in the caplacizumab arm were more than 50% as likely to have a platelet response during treatment (platelet count normalization rate, 1.55; 95% CI, 1.10-2.20; P < .01), and had a 74% reduction in TTP-related death, TTP recurrence, or major thromboembolic events (P < .0001).
A 67% reduction in recurrence was observed among patients treated with caplacizumab vs placebo (9 vs 28; P < .001). All 6 patients who received caplacizumab that relapsed during the follow-up period had evidence of ongoing disease at the end of the treatment period.
Caplacizumab treatment trended towards faster normalization of the 3 organ damage markers: lactate dehydrogenase (LDH), cardiac troponin I, and serum creatinine.
The most frequently reported adverse events associated with caplacizumab were epistaxis, gingival bleeding, and bruising.
The authors concluded that “caplacizumab, through rapid blocking of vWF-mediated platelet aggregation, represents a novel treatment option for patients with aTTP.”
- Scully M, Cataland SR, Peyvandi F, et al. Results of the randomized, double-blind, placebo-controlled, phase 3 HERCULES study of caplacizumab in patients with acquired thrombotic thrombocytopenic purpura. Oral presentation at: American Society of Hematology 59th Annual Meeting & Exposition; December 9-12, 2017; Atlanta, GA.
This article originally appeared on Cancer Therapy Advisor