BioMarin Presents Five-Year Phase 3 Results Reinforcing Long-Term Efficacy and Safety of ROCTAVIAN at International Society on Thrombosis and Haemostasis 2025 Congress

Published: 2025-06-25 06:04:12 ET BMRN

Published on 06/25/2025 at 06:04

SAN RAFAEL - BioMarin Pharmaceutical Inc. (Nasdaq: BMRN) announced new data underscoring the long-term efficacy and safety of ROCTAVIAN were presented at the 33rd Congress of the International Society on Thrombosis and Haemostasis (ISTH) in Washington, D.C., June 21-25, 2025.

The Phase 3 GENEr8-1 trial demonstrated that durable bleed control and sustained factor VIII (FVIII) expression were maintained five years after treatment with ROCTAVIAN. FVIII activity remained consistent with previously reported results, and no new safety signals were observed. Across the entire trial, no participants developed FVIII inhibitors or experienced thromboembolic events, and there were no treatment-related malignancies across the five years of the study.

'I am impressed that the strong efficacy and safety results for ROCTAVIAN are sustained five years after individuals with severe hemophilia A received gene therapy, with only one adult returning to prophylaxis since the last data cut,' said Andrew Leavitt, M.D., director of the University of California San Francisco's program for noncancerous blood disorders and Adult Hemophilia Treatment Center. 'These results highlight the role that gene therapy may play in addressing the burdens of chronic disease management in people living with hemophilia A, while maintaining excellent bleed control.'

Among the 134 individuals who received ROCTAVIAN in the study, the rollover population of 112 patients from the 270-902 noninterventional lead-in study had baseline annualized bleeding rate (ABR) data prospectively collected during a period of at least six months while on routine FVIII prophylaxis prior to receiving ROCTAVIAN, and two of the 112 patients discontinued the study prior to year five.

After five years, FVIII activity was nearly stable compared to year four, with mean FVIII activity in the mild hemophilia range (one-stage assay = 24.0 IU/dL; chromogenic assay = 13.7 IU/dL); 73.5% of participants had FVIII levels in the mild hemophilia to normal range. The mean ABR for treated bleeds for the rollover population was 0.6 bleeds/year after year five. During year five, 77.8% of the remaining participants (n=108) in the rollover population had zero treated bleeds. At the end of year five, 81.3% (n=109) of participants remained off prophylaxis. Additionally, clinically relevant changes in health-related quality of life measures were observed over five years.

'We hope these results demonstrating the long-term durability of gene therapy equip individuals with severe hemophilia A with the knowledge to make informed decisions regarding treatment,' said Dawn Rotellini, Chief Operating Officer at the National Bleeding Disorders Foundation. 'It is meaningful for the bleeding disorders community to see a continued commitment to highlighting the benefits of hemophilia A gene therapy.'

Additional data presented at the meeting described a framework for the measurement of the 'hemophilia-free mind' in people who have received a ROCTAVIAN infusion, which represents an easing of the physical and psychological burden of hemophilia. Researchers leveraged clinical data as well as questionnaires to assess a number of quality of life outcomes from baseline to week 104. The analysis showed that people who received ROCTAVIAN in the Phase 3 GENEr8-1 study experienced improvements across all measures, including bleeding risk, joint pain, injection schedule, physical activity, travel, employment and education, and impact on family members and caregivers.

'These five-year data reinforce our confidence in ROCTAVIAN's profile, showing that people living with severe hemophilia A can experience long-term bleed control without the need for prophylaxis, meaningfully impacting the mental and clinical burdens of this condition,' said Greg Friberg, M.D., Executive Vice President and Chief Research & Development Officer at BioMarin. 'We remain committed to supporting the medical community and individuals living with severe hemophilia A in the clinical adoption of this gene therapy so they can experience the benefits that this treatment can offer.'

About Hemophilia A

Hemophilia A, also called factor VIII (FVIII) deficiency or classic hemophilia, is an X-linked genetic condition caused by missing or defective FVIII, a clotting protein. Although it is passed down from parents to children, about one-third of cases are caused by a spontaneous mutation, a new mutation that was not inherited. Approximately 1 in 10,000 people have hemophilia A.

About ROCTAVIAN

ROCTAVIAN is an adeno-associated virus vector-based gene therapy used for the treatment of adults with severe hemophilia A who do not have antibodies to adeno-associated virus serotype 5 (AAV5), which is determined by a blood test. The one-time infusion works by delivering a functional gene that is designed to enable the body to produce FVIII on its own, reducing the need for ongoing prophylaxis.

The European Commission (EC) granted conditional marketing authorization to ROCTAVIAN on August 24, 2022. The U.S. Food and Drug Administration (FDA) approved ROCTAVIAN on June 29, 2023.

About BioMarin

BioMarin is a global biotechnology company dedicated to translating the promise of genetic discovery into medicines that make a profound impact on the life of each patient. The San Rafael, California-based company, founded in 1997, has a proven track record of innovation with eight commercial therapies and a strong clinical and preclinical pipeline. Using a distinctive approach to drug discovery and development, BioMarin seeks to unleash the full potential of genetic science by pursuing category-defining medicines that offer new possibilities for people living with genetically defined conditions around the world.

Forward-Looking Statements

This press release contains forward-looking statements about the business prospects of BioMarin Pharmaceutical Inc. (BioMarin), including without limitation, statements about: data presented at the 33rd Congress of the International Society on Thrombosis and Haemostasis (ISTH), including the oral and poster presentations; ROCTAVIAN's efficacy, safety and benefits to individuals with hemophilia A, including health-related quality of life and BioMarin's commitment to supporting the medical community and individuals living with severe hemophilia A in the clinical adoption of ROCTAVIAN. These forward-looking statements are predictions and involve risks and uncertainties such that actual results may differ materially from these statements. These risks and uncertainties include, among others: BioMarin's success in the commercialization of ROCTAVIAN; results and timing of current and planned pre-clinical studies and clinical trials of ROCTAVIAN; any potential adverse events observed in the continuing monitoring of the patients in the clinical trials; the content and timing of decisions by the U.S. Food and Drug Administration, the European Commission, and other regulatory authorities and those factors detailed in BioMarin's filings with the Securities and Exchange Commission, including, without limitation, the factors contained under the caption 'Risk Factors' in BioMarin's Quarterly Report on Form 10-Q for the quarter ended March 31, 2025, as such factors may be updated by any subsequent reports. Stockholders are urged not to place undue reliance on forward-looking statements, which speak only as of the date hereof. BioMarin is under no obligation, and expressly disclaims any obligation to update or alter any forward-looking statement, whether as a result of new information, future events or otherwise.

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Katherine Powell

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