Emicizumab-kxwh is effective and safe in treating infants with severe hemophilia A

New positive, topline data for emicizumab-kxwh (Hemlibra; Chugai, Roche, and Genentech), an early preventive treatment for babies with hemophilia A was announced at the 65th American Society of Hematology (ASH) Annual Meeting and Exposition in San Diego, California.¹

The data demonstrated that emicizumab-kxwh achieved meaningful bleed control in babies aged up to 12 months and was well tolerated. Results were from the phase 3, descriptive, single-arm HAVEN 7 (NCT 04431726) study, evaluating the safety, efficacy, and pharmacokinetics of subcutaneous emicizumab-kxwh in infants with severe hemophilia A without factor VIII inhibitors.^1,2

Emicizumab-kxwh is a bispecific factor IXa- and factor X-directed antibody designed to bring factor IXa and factor X, proteins required to activate the natural coagulation cascade and restore the blood clotting process for hemophilia A patients, together.¹

The preventive treatment can be administered via injection of a ready-to-use subcutaneously solution once per week every 2 weeks or 4 weeks.¹

Standard of care for hemophilia is considered to be regular prophylaxis initiated at a young age by the World Federation of Hemophilia. For many babies with hemophilia A, because of the high treatment burden, prophylaxis is not started until after the first year of life.¹

Data results from 55 participants in the HAVEN 7 study revealed at nearly 2 year follow-up (101.9 weeks) 30 participants (54.5%) did not have any bleeds that required treatment. In addition, 9 patients (16.4%) did not have treated or untreated bleeds.¹

In all, 207 bleeds occurred in 46 study participants (83.6%). Among these individuals, 87.9% of these bleeds were as a result of trauma, according to a news release from Genentech. For treated bleeds, the model-based annualized bleeding rate (95% CI) was 0.4 (0.30-0.63).¹

No treatment-related serious adverse events, intracranial hemorrhages or deaths were reported, and no new safety signals were observed. Two participants (3.6%) tested positive for factor VIII inhibitors, and no individuals tested positive for anti-drug antibodies. Overall, results were consistent with interim analysis from previous phase 3 HAVEN studies.¹

“Hemophilia A can have a devastating impact on any patient, but this is especially true for infants, where the emotional and physical stress due to frequent hospital visits, treatment administration, and other worries can be distressing for babies and their parents and caregivers,” said Steven Pipe, M.D., professor of pediatrics and pathology, University of Michigan.

“These results reinforce the benefit of starting prophylaxis as soon as possible after birth, as well as for the use of subcutaneous treatments, which are especially valuable in young babies where access to veins can be very difficult.”¹

Also presented at ASH were results of additional research on biomarkers in the HAVEN 7 study. Results demonstrated that pharmacodynamic profiles of emicizumab-kxwh in babies were, “consistent with those previously observed in older children and adults with hemophilia A,” Genentech stated.¹

The most common side effects for emicizumab-kxwh include injection site reactions, joint pain, and headache.¹

According to the news release, emicizumab-kxwh was created by Chugai Pharmaceutical Co, and is being co-developed by Chugai, Roche Group, and Genentech.¹

References:

1. New data reinforce the benefit of early preventative treatment with Genentech’s Hemlibra (emicizumab-kxwh) for babies with severe hemophilia A. Genentech. Press release. December 9, 2023. Accessed December 12, 2023. https://www.gene.com/media/press-releases/15014/2023-12-09/new-data-reinforce-the-benefit-of-early-
2. A study to Evaluate the efficacy, safety, pharmacokinetics, and pharmacodynamics of subcutaneous emicizumab in participants from birth to 12 months of age with hemophilia A without inhibitors (HAVEN 7). Clinicaltrials.gov. Updated November 18, 2023. Accessed December 12, 2023. https://clinicaltrials.gov/study/NCT04431726