Real-world use of protein C concentrate for the treatment of patients with protein C deficiency: an international registry

Authors: Manco-Johnson, M; Brons, P; Knoebl, P; Wang, M; Siffel, C; Turecek, PL; Gazda, HT

Affiliations: Hemophilia and Thrombosis Center, University of Colorado Anschutz Medical Campus, Aurora, CO, USA. Department of Pediatric Hematology, Radboudumc Amalia Children’s Hospital, Nijmegen, Netherlands. Division of Hematology and Hemostasis, Medical University of Vienna, Vienna, Austria. Takeda Development Center Americas, Inc., Cambridge, MA, USA; College of Allied Health Sciences, Augusta University, Augusta, GA, USA. Baxalta Innovations GmbH, a Takeda company, Vienna, Austria.

Publication: Journal of thrombosis and haemostasis; 2025

ABSTRACT: BACKGROUND: Published reports on the real-world use of protein C concentrate have been limited to case reports or small case series. OBJECTIVES: To collect and assess data on the medical diagnoses, treatment regimens, safety outcomes, and treatment outcomes of patients receiving protein C concentrate in routine clinical practice. METHODS: This was a prospective, open-label, registry-based study conducted at 26 sites in Europe and the USA. Data was collected from the medical records of patients of all ages who received treatment with protein C concentrate. The primary endpoints were medical diagnoses associated with protein C concentrate treatment, treatment regimens, and the safety of protein C concentrate (incidence of related adverse events [AEs] and all serious AEs [SAEs]). RESULTS: Between June 23, 2010, and June 22, 2015, 43 patients, including 25 with severe congenital protein C deficiency (SCPCD) and 18 with severe acquired protein C deficiency, were enrolled in the study, all of whom were included in the analysis. In total, 306 treatment courses of protein C concentrate were documented during the study, for treatment of acute thrombotic episodes, short-term replacement, and long-term prophylaxis. Most patients (76%) with SCPCD were receiving long-term prophylaxis. Overall, 124 AEs were reported in 27 patients (63%); 17 patients experienced SAEs. Only 2 AEs (SAEs of abdominal pain and lower extremity pain) in 1 patient were considered possibly related to protein C concentrate. CONCLUSION: The results of this study provide insights into the real-world use of protein C concentrate in clinical practice in Europe and the USA.