MEPSEVII

Reevaluation.

Unfavourable opinion for reimbursement in the treatment of non-neurological manifestations of Mucopolysaccharidosis VII (MPS VII; Sly syndrome).

Role in the care pathway?

MPS VII is a multisystemic disease that requires multidisciplinary, global management tailored to each patient, the primary objectives of which are:

• to improve or slow down the multisystemic progression of the disease;
• to improve the patient’s quality of life and social, school or professional integration.

Recourse to hematopoietic stem cell transplantation (HSCT) is not mentioned in the French national diagnostic and care protocol (PNDS) for MPS VII patients. No studies have demonstrated the effect of HSCT in these patients. Only a few clinical cases have been published in the literature, with no robust demonstration and with heterogeneous results from one patient to another. According to expert opinion, this can sometimes be performed in the absence of any alternative, in certain situations only, since it is a complex and restrictive therapy, requiring chemotherapy and a compatible donor.

Role of the medicinal product in the care pathway:

Considering:

• on the basis of the available data, demonstration of efficacy solely with respect to a biological endpoint - i.e., a reduction in urinary excretion of GAG (dermatan sulfate) - with MEPSEVII (vestronidase alfa), with no demonstrated benefit on a clinically relevant endpoint,
• the absence of an established correlation between the reduction in urinary excretion of GAG and a clinical benefit,
• the absence of efficacy of MEPSEVII (vestronidase alfa) on neurological symptoms, which are an important component of the disease,
• the safety profile of MEPSEVII (vestronidase alfa) characterised by infusion reactions, including hypersensitivity reactions, which are important identified risks in the risk management plan, as well as adverse effects such as diarrhoea, ataxia, confusion, abdominal pain, vomiting, febrile convulsion,
• the restriction related to the method of administration, as an intravenous infusion every 2 weeks,
• the absence of demonstration of a benefit in terms of quality of life of patients treated with MEPSEVII (vestronidase alfa),

MEPSEVII (vestronidase alfa) has no role in the care pathway for non-neurological manifestations of Mucopolysaccharidosis VII (MPS VII; Sly syndrome).