Presenting Author: Jennifer Wang, PharmD, Sanofi, Cambridge, MA
Co-Authors: Laurence Pollissard, MSc, Sanofi, Gentilly, France; Jennifer Wang, MA Statistics, Sanofi, Cambridge, MA; Marco Rossetti, BSBA, and Synne Wing, MSW, EmpiraMed, A StoryCatch Partners Company, Maynard, MA
BACKGROUND: Immune thrombotic thrombocytopenic purpura (iTTP) is a rare, life-threatening autoimmune disorder that results from severe ADAMTS13 deficiency.1 Real-world data on long-term patient-reported outcomes (PROs) and health-related quality of life (HRQOL) in iTTP remain limited.
OBJECTIVE: To describe long-term PROs in patients newly diagnosed with iTTP in the United States after hospital discharge and the first iTTP episode who received caplacizumab plus therapeutic plasmatic exchange (TPE) and immunosuppression (ie, the caplacizumab group) or standard therapy TPE plus immunosuppression (ie, the TPE group).
METHODS: This 24-month prospective, observational study planned to enroll approximately 100 adults newly diagnosed with iTTP (≥18 years) into caplacizumab (enrolled within 1 month after discharge) and TPE (enrolled within 12 months after discharge) group. The data were collected using validated instruments, including the PROMIS-Cognition Short Form 8a; Headache Impact Test-6; EQ-5D-5L; Short-Form 36 Health Survey, Version 2 (SF-36v2); Hospital Anxiety and Depression Scale; and Work Productivity and Activity Impairment Questionnaire. Descriptive analyses were conducted and presented as means (standard deviation [SD]) unless otherwise specified.
RESULTS: This analysis included 35 patients in the caplacizumab group with a mean age of 38 years (SD, 11.48). Patients were enrolled 15 (SD, 9.42) days after receiving their first dose of caplacizumab. The TPE group (n=3) was too small for meaningful analysis, and the results are not shown. From baseline to 24 months, cognitive function remained stable and slightly above the general population norms, with PROMIS T-scores improving from 52.90 (SD, 9.79) to 55.62 (SD, 8.01). QOL improved across all SF-36v2 domains, with a physical component summary score that increased from 40.12 (SD, 8.74) to 50.23 (SD, 9.46) and mental component summary score that increased from 41.68 (SD, 12.41) to 48.72 (SD, 8.98), approaching population norms. Headache severity decreased from 52.30 (SD, 8.80) to 46.25 (SD, 9.11). EQ-5D-5L health utility scores improved from 0.73 (SD, 0.24) to 0.88 (SD, 0.17). Anxiety and depression scores decreased from 9.36 (SD, 5.17) to 7.25 (SD, 4.79) and from 5.00 (SD, 3.48) to 2.75 (SD, 2.50), respectively. Over 24 months, significant improvements were observed in work productivity measures, including activity impairment that decreased from 71.11 (SD, 36.44) to 16.67 (SD, 5.77), overall productivity loss that decreased from 91.67 (SD, 7.64) to 16.67 (SD, 5.77), presenteeism that decreased from 76.67 (SD, 20.82) to 16.67 (SD, 5.77), and absenteeism that decreased from 84.00 (SD, 33.15) to 0 (SD, 0).
CONCLUSION: This study highlights improvements in PROs over 24 months in patients with iTTP receiving caplacizumab plus TPE at initial diagnosis, providing first real-world evidence of long-term QOL outcomes. However, limitations such as underrecruitment, small TPE group size, and high dropout rates prevent attributing these gains directly to caplacizumab. Larger studies that have well-matched comparator groups are needed to assess caplacizumab’s impact on HRQOL in patients with iTTP.
- Scully M, Cataland SR, Peyvandi F, et al. Caplacizumab treatment for acquired thrombotic thrombocytopenic purpura. N Engl J Med. 2019;380:335-346.