PB1183 - Treatment Outcomes of First-Line Immunosuppressive Treatments in Patients with Acquired Hemophilia A: A 25-year Cohort Experience and Network Meta-Analysis

Tuesday, June 25, 2024

13:45 – 14:45 ICT

Room: Exhibition Hall

Presenting Author(s)

Tarinee Rungjirajittranon

Lecturer
Department of Medicine, Faculty of Medicine Siriraj Hospital, Mahidol University
Bangkok, Krung Thep, Thailand

Co-Author(s)

Bundarika Suwanawiboon, MD

Assistant Professor
Department of Medicine, Faculty of Medicine Siriraj Hospital, Mahidol University
Bangkok, Krung Thep, Thailand
YN

Yupa Nakkinkun

Technician
Faculty of Medicine Siriraj Hospital, Mahidol Univerisity
Bangkok, Krung Thep, Thailand
NL

Nattawut Leelakanok

Pharmacist
Department of Clinical Pharmacy, Faculty of Pharmaceutical Sciences, Burapha University,
Chonburi, Chon Buri, Thailand
TK

Thanapon Kaokunakorn

Fellow
, Department of Medicine, Faculty of Medicine Siriraj Hospital, Mahidol University
Bangkok, Krung Thep, Thailand
YC

Yingyong Chinthammitr

Assistant Professor
Siriraj hospital
Bangkok, Krung Thep, Thailand
WO

Weerapat Owattanapanich

Associate Professor
Department of Medicine, Faculty of Medicine Siriraj Hospital, Mahidol University
Bangkok, Krung Thep, Thailand
TR

Theera Ruchutrakool

Associate Professor
Department of Medicine, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
Bangkok, Krung Thep, Thailand

Background: Acquired hemophilia A (AHA), characterized by life-threatening bleeding events, requires interventions that promptly stop bleeding and eliminate antibodies through immunosuppressive treatments (IST).

Aims: To evaluate treatment outcomes: complete remission rate (CR) and relapse rate (RR) for each IST

Methods: Seventy-six newly diagnosed AHA patients were enrolled. The primary outcomes were CR, RR, and mortality rates, while identifying factors associated with treatment outcomes served as a secondary aim. Subsequently, a systematic review and network meta-analysis compared CR and RR for each IST were conducted.

Results: Patients were equally divided based on inhibitor intensity (cut-off level of 20 Bethesda units). Cyclophosphamide and prednisolone (CP) were the primary first-line IST (64), followed by steroid monotherapy (6), rituximab-based (4), CVP regimen (1), and no IST (1). Although our study showed non-significant differences in CR, RR, and mortality rates among various ISTs, the low-titer inhibitor group achieved a significantly higher CR rate than the high-titer group (86.8% vs. 62.2%, P = 0.014). Inhibitor intensity significantly influenced the CR rate, with an odd ratio of 0.26 (P = 0.021). The overall median relapse-free survival (RFS) was 37.13 months, with CP demonstrating protective effects against relapse (RFS 43.1 vs. 22.6 months in the non-CP group, hazard ratio 0.24, P = 0.002). Network meta-analysis, including 1,476 patients for CR and 636 patients for RR, confirmed the superior efficacy of CP and rituximab-based regimens over steroid monotherapy (risk differences (RD) 0.15 for both groups, P < 0.05), and lower RR ( RD -0.13 and -0.15, P < 0.05) than those receiving steroid monotherapy. CP and rituximab-based regimens exhibited comparable CR and RR (RD 0.00 and -0.02, P > 0.05).

Conclusion(s): Our study highlights adverse outcomes associated with high-titer inhibitors in AHA, emphasizing the limited effectiveness of steroid monotherapy. CP emerged as an effective first-line IST, especially for patients with restricted access to rituximab.