(14) Bleed patterns in emicizumab-treated infants with hemophilia A: an exploratory analysis of the HAVEN 7 study

Location: Exhibit Hall D

Co-Author Not Presenting(s)

SC

Shannon L. Carpenter, MD, MS

Interim Division Director
Children’s Mercy Hospital
Kansas City, Montana, United States

First Author Presenting(s)

Dakota Rosenfelt, PharmD, RPh, MBA

Senior Medical Science Liaison
Genentech, Inc.
Atlanta, Georgia, United States

Co-Author Not Presenting(s)

ET

Eunice Tzeng, PharmD

Principal Medical Science Director
Genentech, Inc.
South San Francisco, California, United States
Elise Lim, PhD

Senior Statistical Scientist
Genentech, Inc.
San Francisco, California, United States
Steven W. Pipe, MD (he/him/his)

Professor of Pediatrics and Pathology
University of Michigan
Ann Arbor, Michigan, United States

Title: Bleed patterns in emicizumab-treated infants with hemophilia A: an exploratory analysis of the HAVEN 7 study

Abstract : Basis of inquiry: Emicizumab initiation in infants with hemophilia A (HA) may mitigate spontaneous/traumatic bleeding risk, including intracranial hemorrhage (ICH). In HAVEN 7 (NCT04431726), emicizumab demonstrated effective bleed control and was well tolerated in infants with severe HA without factor (F)VIII inhibitors.

Objective: To present an exploratory analysis of HAVEN 7 bleeding patterns.

Methods: Participants had no history of/minimal exposure (≤5 days) to FVIII-containing treatments, no prior emicizumab use, and no evidence of ICH. Bleeding patterns relative to age, type, and location were explored.
Findings: Fifty-five male infants completed 52 weeks of emicizumab at primary analysis (May 22, 2023). Median (range) treatment duration was 100.3 (52–118) weeks. At informed consent, median (range) age was 4.0 (9 days–11 months) months. Thirty (54.5%) participants were minimally treated; 25 (45.5%) previously untreated. Before emicizumab initiation, 36 (65.5%) participants reported 77 bleeds (25 [32.5%] spontaneous; 19 [24.7%] traumatic).
Overall, 195 bleeds occurred in 46 (83.6%) emicizumab-treated participants. Model-based annualized bleed rates (ABRs; 95% confidence interval) for treated and all bleeds were 0.40 (0.30–0.63) and 2.0 (1.49–2.66), respectively. Three (1.5%) bleeds occurred in participants aged 0– < 6 months; 5 (2.6%), 27 (13.8%), and 160 (82.1%) occurred in those aged 6– < 9, 9– < 12, and ≥12 months, respectively. Overall, 25/46 (54.3%) participants reported ≥1 treated bleed (42 overall, all traumatic); none in participants aged 0– < 6 months; 3 (7.1%), 10 (23.8%), and 29 (69.0%) in those aged 6– < 9, 9– < 12, and ≥12 months, respectively. No treated spontaneous bleeds occurred.
Most bleeds occurred on the head (151/195 [77.4%]); 94/151 (62.2%) were mouth/nose bleeds. No ICH occurred.

Conclusions: Emicizumab maintained low ABRs; all treated bleeds were traumatic. No treated spontaneous bleeds or ICH occurred. Bleeding patterns observed were similar to bruising/injury patterns in non-hemophilic infants. Bleeds increased with age as participants gained mobility.