Last reviewed · How we verify
Mepsevii (VESTRONIDASE ALFA)
Mepsevii works by replacing the deficient enzyme beta-glucuronidase in patients with MPS-VII.
Mepsevii (Vestronidase alfa) is a small molecule lysosomal beta glucuronidase enzyme replacement therapy developed by Ultragenyx Pharmaceuticals. It is used to treat Mucopolysaccharidosis type VII (MPS-VII), a rare genetic disorder caused by a deficiency of the enzyme beta-glucuronidase. Mepsevii is FDA-approved and remains a patented product. Key safety considerations include potential infusion reactions and the risk of antibody formation. As a replacement therapy, Mepsevii aims to restore normal enzyme function in patients with MPS-VII.
At a glance
| Generic name | VESTRONIDASE ALFA |
|---|---|
| Sponsor | Ultragenyx Pharm Inc |
| Drug class | Lysosomal beta Glucuronidase [EPC] |
| Modality | Enzyme |
| Therapeutic area | Metabolic |
| Phase | FDA-approved |
| First approval | 2017 |
Mechanism of action
Mucopolysaccharidosis VII (MPS VII or Sly syndrome) is lysosomal disorder characterized by the deficiency of GUS that results in GAG accumulation in cells throughout the body leading to multisystem tissue and organ damage. Vestronidase alfa-vjbk is recombinant form of human GUS and is intended to provide exogenous GUS enzyme for uptake into cellular lysosomes. Mannose-6-phosphate (M6P) residues on the oligosaccharide chains allow binding of the enzyme to cell surface receptors, leading to cellular uptake of the enzyme, targeting to lysosomes and subsequent catabolism of accumulated GAGs in affected tissues.
Approved indications
- Mucopolysaccharidosis, MPS-VII
Boxed warnings
- WARNING: ANAPHYLAXIS Anaphylaxis has occurred with MEPSEVII administration, as early as the first dose [see Warnings and Precautions ( 5.1 )] , therefore appropriate medical support should be readily available when MEPSEVII is administered. Closely observe patients during and for 60 minutes after MEPSEVII infusion [see Dosage and Administration ( 2.2 ), Warnings and Precautions ( 5.1 )]. Immediately discontinue the MEPSEVII infusion if the patient experiences anaphylaxis [see Dosage and Administration ( 2.2 ), Warnings and Precautions ( 5.1 )]. WARNING: ANAPHYLAXIS See full prescribing information for complete boxed warning. Anaphylaxis has occurred with MEPSEVII administration, as early as the first dose ( 5.1 ), therefore appropriate medical support should be readily available when MEPSEVII is administered. Closely observe patients during and for 60 minutes after MEPSEVII infusion ( 2.2 , 5.1 ). Immediately discontinue the MEPSEVII infusion if the patient experiences anaphylaxis ( 2.2 , 5.1 ).
Common side effects
- Infusion site extravasation
- Diarrhea
- Rash
- Anaphylaxis
- Infusion site swelling
- Peripheral swelling
- Pruritus
- Febrile Convulsion
- Immunogenicity
- Anti-vestronidase alfa-vjbk antibodies (ADA)
- Neutralizing antibodies (NAb)
Key clinical trials
- Mucopolysaccharidosis VII Disease Monitoring Program
- PEARL (PrEnAtal Enzyme Replacement Therapy for Lysosomal Storage Disorders) (PHASE1)
- Expanded Access to Mepsevii
- A Study of UX003 Recombinant Human Beta-Glucuronidase (rhGUS) Enzyme Replacement Therapy in Subjects With Mucopolysaccharidosis Type 7, Sly Syndrome (MPS 7) (PHASE3)
- A Phase 3 Study of UX003 Recombinant Human Betaglucuronidase (rhGUS) Enzyme Replacement Therapy in Patients With Mucopolysaccharidosis Type 7 (MPS 7) (PHASE3)
- Study of UX003 Recombinant Human Beta-Glucuronidase (rhGUS) Enzyme Replacement Treatment in Mucopolysaccharidosis Type 7, Sly Syndrome (MPS 7) Patients Less Than 5 Years of Age (PHASE2)
- An Open-Label Phase 1/2 Study to Assess the Safety, Efficacy and Dose of Study Drug UX003 Recombinant Human Beta-glucuronidase (rhGUS) Enzyme Replacement Therapy in Patients With Mucopolysaccharidosis Type 7 (MPS 7) (PHASE1,PHASE2)
- An Open-Label Treatment Protocol With UX003 rhGUS Enzyme Replacement Therapy for an Advanced Stage MPS 7 Patient
Patents
| Patent | Expiry | Type |
|---|---|---|
| Biologic Exclusivity |
Primary sources
Every claim on this page is sourced from regulatory or scientific primary sources. See our editorial policy for full methodology.
| Source | Used for |
|---|---|
| FDA label | Mechanism, indications, dosing, boxed warnings, drug interactions |
| ClinicalTrials.gov | Trial enrolment, design, endpoints, results |
| FDA Orange Book | Patents + exclusivity |
Competitive intelligence
For the full competitive landscape — auto-detected comparators, recent regulatory actions across the set, upcoming PDUFA, patent timeline, sponsor landscape:
- Mepsevii CI brief — competitive landscape report
- Mepsevii updates RSS · CI watch RSS
- Ultragenyx Pharm Inc portfolio CI