Vosoritide Adverse Events: What the Label and Studies Report

How This Page Frames Vosoritide

Vosoritide is a prescription medicine, a modified analogue of C-type natriuretic peptide (CNP) that acts on natriuretic peptide receptor B to dampen overactive FGFR3 signalling in the growth plate. Its approved indication, at label level, is the treatment of achondroplasia in children who still have open epiphyses. A regulatory review of its approval pathway described vosoritide as the first disease targeted pharmacological option authorised for achondroplasia, with approvals granted in multiple regions following the pivotal randomised programme (PMID 38024582). Any population outside that approved indication, including hypochondroplasia, is investigational.

This page summarises adverse events as they appear in product labeling and in published trials. It does not contain dosing directions, administration steps or product sourcing information. This page is for educational purposes only and is not medical advice; consult a licensed physician about any symptom, medicine or treatment decision.

Boxed Warning Status

Labeling for the approved vosoritide product does not carry a boxed warning. Because prescribing information is revised as new data accumulate, the current approved labeling held by a prescriber or dispensing pharmacy is the authoritative version, and this page should not be treated as a substitute for it.

Warnings and Precautions in Labeling: What Studies Report

Decreased blood pressure

The principal labeling warning for vosoritide concerns transient decreases in blood pressure, which may present with symptoms such as dizziness, fatigue or nausea. The pharmacological basis is the vasodilatory activity shared across the natriuretic peptide family; a review of non growth hormone agents in short stature described vosoritide as a CNP analogue developed specifically to restrain FGFR3 driven growth plate inhibition, with the natriuretic peptide class carrying known cardiovascular activity (PMID 34196930). Labeling also directs attention to children with significant cardiac or vascular disease, for whom blood pressure effects warrant closer clinician oversight. Questions about blood pressure, dizziness or fainting belong with the prescribing clinician rather than with any general reference page.

Use once growth plates close

The approved indication is limited to children with open epiphyses, and labeling frames continued treatment after epiphyseal closure as outside the authorised use. A systematic literature review of the burden and treatment of achondroplasia discussed how growth plate status defines the treatable window for CNP analogue therapy and how unmet needs persist beyond that window (PMID 37382866).

Injection site reactions

Because vosoritide is given by subcutaneous injection, local reactions are the most consistently described adverse reaction category in both labeling and trials. A narrative review of clinical and real-world evidence reported that injection site reactions dominated the adverse event profile across available datasets and were generally described as mild and self limiting (PMID 40821249).

Common Adverse Reactions Grouped by Body System: What Studies Report

The table below groups the adverse reaction categories that appear in approved labeling and in published safety reporting. Frequencies are presented only where a cited source described them; percentages are not reproduced where the cited sources did not supply them.

Trial Safety Reporting by Study: What Studies Report

Phase 3 randomised trial in children aged 5 to under 18 years

The study was a randomised, double blind, placebo controlled, multicentre phase 3 trial of once daily subcutaneous vosoritide at 15 micrograms per kilogram per day, and researchers reported an adjusted mean difference in annualised growth velocity of 1.57 cm per year favouring vosoritide over placebo at 52 weeks (PMID 32891212). In the same trial, researchers described adverse events as mostly mild, with injection site reactions among the events reported most often (PMID 32891212).

Phase 3 extension

An ongoing phase 3 extension study reported sustained growth promoting effects with continued daily treatment in children with achondroplasia, and researchers described the safety profile over extended exposure as consistent with the controlled phase (PMID 39740666).

Phase 2 trial in infants and young children aged 3 to 59 months

A multinational, randomised, double blind, placebo controlled phase 2 trial evaluated daily subcutaneous vosoritide in children with achondroplasia aged 3 to 59 months, a group in which cardiovascular and feeding related tolerability is of particular interest given age and body size, and researchers reported safety and growth outcomes for that younger cohort (PMID 37984383).

Investigational use in hypochondroplasia

Use of vosoritide in hypochondroplasia is investigational and is not an approved indication. A phase 2 trial examined vosoritide treatment in children with hypochondroplasia and researchers reported growth and safety outcomes for that exploratory population (PMID 38813446). Findings from an investigational population do not extend the approved labeling.

Real-World Reports: What Studies Report

Post approval datasets add observational context to the randomised findings. A systematic review and meta analysis of multinational real-world clinical evidence pooled post approval cohorts and reported growth outcomes alongside tolerability observations broadly aligned with the registration trials (PMID 41424367). A single centre real-world cohort study described growth outcomes in children with achondroplasia treated with vosoritide in routine care, a setting where adherence, injection burden and local reactions are observed outside protocol conditions (PMID 42238253). A review of clinical and real-world evidence summarised both strands and reported that the tolerability signal has remained centred on injection site events (PMID 40821249).

Preclinical Signals in the CNP Class: What Studies Report

Preclinical work on the CNP pathway informs mechanism but does not establish human adverse event rates. In a mouse model of streptozotocin induced type 1 diabetes, researchers reported that vosoritide produced phosphodiesterase 2 sensitive anti arrhythmogenic effects in isolated hearts, underlining that CNP receptor signalling is active in cardiac tissue as well as cartilage (PMID 40965622). Separately, researchers reported that a collagen binding CNP construct enhanced chondrogenesis and osteogenesis in preclinical models, illustrating continued engineering of the peptide class for skeletal targets (PMID 41433092). Neither animal or laboratory finding describes clinical safety in children.

Limits of the Published Safety Picture

• Exposure duration. Controlled randomised data cover a defined treatment period, with longer observation coming from an open label extension in which researchers reported continued growth effects (PMID 39740666).
• Population breadth. Trials enrolled defined age ranges, including a dedicated cohort aged 3 to 59 months (PMID 37984383), so event rates may not generalise beyond those groups.
• Background disease. Achondroplasia itself carries orthopaedic, otological and respiratory complications, which a systematic literature review catalogued as part of the condition's burden and which complicate attribution of events to treatment (PMID 37382866).
• Observational design. Real-world cohorts and pooled analyses lack randomisation and blinding, a limitation acknowledged in a systematic review and meta analysis of multinational evidence (PMID 41424367).

Where Symptom Questions Belong

Nothing on this page assesses whether any particular event is expected, acceptable or manageable for a particular child. Labeling frames blood pressure effects and injection site reactions as items for clinician monitoring, and published trials reported events under protocol supervision (PMID 32891212). Questions about symptoms, monitoring, treatment continuation or alternatives are for the prescribing clinician, who holds the current labeling and the clinical history.

References

• Once-daily, subcutaneous vosoritide therapy in children with achondroplasia: a randomised, double-blind, phase 3, placebo-controlled, multicentre trial (Lancet, 2020)
• Vosoritide therapy in children with achondroplasia aged 3-59 months: a multinational, randomised, double-blind, placebo-controlled, phase 2 trial (The Lancet Child & Adolescent Health, 2024)
• Sustained growth-promoting effects of vosoritide in children with achondroplasia from an ongoing phase 3 extension study (Med, 2025)
• Vosoritide treatment for children with hypochondroplasia: a phase 2 trial (EClinicalMedicine, 2024)
• Real-world outcomes of vosoritide in achondroplasia: A systematic review and meta-analysis of multinational clinical evidence (Genetics in Medicine, 2026)
• Real-world growth outcomes of vosoritide in children with achondroplasia: a single-center cohort study (Journal of the Endocrine Society, 2026)
• Vosoritide (Voxzogo) for Achondroplasia: A Review of Clinical and Real-World Evidence (Cureus, 2025)
• Burden and Treatment of Achondroplasia: A Systematic Literature Review (Advances in Therapy, 2023)
• Vosoritide, a miracle drug, covering unmet need in achondroplasia: A regulatory update (Intractable & Rare Diseases Research, 2023)
• Non-GH Agents and Novel Therapeutics in the Management of Short Stature (Indian Journal of Pediatrics, 2021)
• The CNP analogue vosoritide mediates PDE2-sensitive anti-arrhythmogenic effects in mouse hearts with STZ-induced type 1 diabetes (Basic Research in Cardiology, 2025)
• Collagen-binding C-type natriuretic peptide enhances chondrogenesis and osteogenesis (JCI Insight, 2026)