SAN RAFAEL, Calif., May 20, 2026
BioMarin Pharmaceutical Inc. announced positive topline results from the pivotal Phase 3 CANOPY-HCH-3 trial evaluating VOXZOGO® (vosoritide) in children with hypochondroplasia, a rare genetic skeletal disorder characterized by impaired bone growth and disproportionate short stature. The study successfully met its primary endpoint, demonstrating a highly statistically significant improvement in annualized growth velocity (AGV) compared with placebo after 52 weeks of treatment, marking a major milestone in the development of the first potential approved therapy for hypochondroplasia.
Phase 3 Study Shows Strong Growth Benefits
According to the company, children treated with VOXZOGO achieved an increase in annualized growth velocity of +2.33 cm/year versus placebo at week 52, with a highly significant p-value of p<0.0001. The study also demonstrated statistically significant improvements in standing height and height Z-score, further reinforcing the therapy’s potential to address growth deficits associated with hypochondroplasia.
Importantly, the trial also met a key secondary endpoint showing statistically significant improvements in arm span (p=0.004), a measurement closely associated with functional independence, daily activities, and physical reach. BioMarin emphasized that these improvements may translate into meaningful quality-of-life benefits for children living with the condition.
Dr. Andrew Dauber, lead investigator and Chief of Endocrinology at Children’s National Hospital in Washington, D.C., stated that the data represent a significant milestone for patients who previously had no approved treatment options. He noted that the findings may signal a new era in the clinical management of hypochondroplasia.
Safety Profile Consistent with Existing VOXZOGO Experience
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The company reported that the safety findings observed in the CANOPY-HCH-3 study were consistent with the established safety profile of VOXZOGO in achondroplasia, with no new safety signals identified during the trial. The most commonly reported side effects remained consistent with prior studies and included injection site reactions, vomiting, decreased blood pressure, stomach pain, and joint pain.
BioMarin highlighted that the therapy’s safety and tolerability profile continues to support its broader development strategy across skeletal dysplasia indications. The company plans to present the full dataset from the Phase 3 study at an upcoming medical conference later this year.
The randomized, double-blind, placebo-controlled global study enrolled 80 children aged 3 to 17 years with hypochondroplasia. The trial evaluated multiple endpoints, including growth velocity, standing height, arm span, body proportions, quality of life measures, and long-term safety assessments. Patients enrolled in the study will continue into a long-term extension phase to further evaluate durability and long-term outcomes.
Regulatory Filings Planned in U.S. and Europe
Following the positive pivotal data, BioMarin confirmed plans to submit a supplemental New Drug Application (sNDA) to the U.S. Food and Drug Administration (FDA) during the third quarter of 2026. Additional regulatory submissions to the European Medicines Agency (EMA) and other global health authorities are expected to follow.
Hypochondroplasia currently has no FDA- or EMA-approved therapies, making VOXZOGO a potentially first-in-class treatment option for affected children worldwide. The company believes the positive Phase 3 results could significantly expand the commercial and clinical impact of VOXZOGO beyond its current approved use in achondroplasia.
VOXZOGO is already approved in multiple global markets, including the United States, Europe, Japan, and Australia, for increasing linear growth in children with achondroplasia who have open growth plates. The therapy works by targeting pathways involved in bone growth regulation and has become one of the leading treatments in skeletal dysplasia.
BioMarin continues to strengthen its leadership position in rare genetic diseases and skeletal disorders, leveraging its expertise in precision therapies aimed at genetically defined conditions. The successful outcome of the CANOPY-HCH-3 study further expands the company’s pipeline momentum and reinforces growing interest in therapies addressing rare pediatric growth disorders.
Source: BioMarin press release
