NUCALA (mépolizumab) - Syndrome hyperéosinophilique

Key points

Favourable opinion for reimbursement as an add-on treatment for adult patients with inadequately controlled lymphocytic or idiopathic hypereosinophilic syndrome.

Unfavourable opinion for reimbursement in the other MA situations.

What therapeutic improvement?

Therapeutic improvement in the management of inadequately controlled lymphocytic or idiopathic hypereosinophilic syndrome.

Role in the care pathway?

Hypereosinophilic syndromes (HES) are a group of rare diseases associated with tissue damage related to eosinophil infiltration, in which the clinical manifestations are heterogeneous and of variable severity. The main objectives of treatment are to reduce symptoms and control eosinophilia. It is also essential to prevent any adverse effects of the treatments used in order to ensure control of the disease and prevent long-term complications.

The therapeutic management should be adapted based on the severity of the disease and the type of HES:

• for reactional HES with an identified cause (iatrogenic, parasitic or cancer-related), management is specific and tailored to the aetiology;
• for F/P-positive chronic eosinophilic leukaemia clonal neoplastic HES, imatinib is the first-line treatment in patients with this rearrangement; for F/P-negative chronic eosinophilic leukaemia clonal neoplastic HES or MDS/MPD, imatinib or, in some cases, hydroxyurea may be used;
• for lymphocytic and idiopathic HES, the management is as follows:
  • as first-line treatment: corticosteroids are generally administered at moderate or high doses (0.5 to 1 mg/kg of prednisone equivalent); corticosteroids usually enable normalisation of eosinophil levels and an improvement in clinical signs, but it is common for the disease to reappear on gradual dose tapering;
  • as second-line treatment: immunomodulatory therapies, such as PEGylated interferon alfa or hydroxyurea, are proposed as corticosteroid-sparing treatments; these are used off-label.

Role of the medicinal product in the care pathway

NUCALA (mepolizumab) is a first-line treatment in patients with lymphocytic or idiopathic hypereosinophilic syndrome inadequately controlled by corticosteroids and/or immunomodulators.

Since it has not been assessed in these subpopulations, NUCALA (mepolizumab) has no role in the care pathway for clonal neoplastic HES (in particular F/P+ chronic eosinophilic leukaemias) for which the first-line treatment is imatinib.

Special recommendations

Given the specificities of treatment of this rare disease and the implementation of long-term patient follow-up in the context of the national COHESion cohort, the Committee recommends that decisions to initiate and discontinue treatment with mepolizumab be taken after a documented proposal resulting from a multidisciplinary team meeting within the national network of specialists involved in the diagnosis and treatment of hypereosinophilic syndromes (Hypereosinophilic syndrome reference centre​ - CEREO). Regular follow-up of patients within one of these centres is essential to ensure the efficacy of treatment and monitor its safety.