A Compassionate Use Open-Label Study of Anti IL-5 (Mepolizumab) Treatment in Subjects with Hypereosinophilic Syndrome

ID Number 07-1263

Principal Investigator(s)
Paula J Busse

Department(s) or Division(s)
Clinical Immunology


Mepolizumab is being developed by GlaxoSmithKline and is a type of biologic drug called a monoclonal antibody that can block the actions of a protein molecule called interleukin 5 (IL-5). IL-5 is thought to increase the level of eosinophils, a type of white blood cell, in the blood or tissues.  An elevated level of eosinophils in the blood is called hypereosinophilia.  Prolonged hypereosinophilia may lead to physical symptoms due to damage in different organ systems e.g. the lung. The combination of prolonged hypereosinophilia and eosinophil-related disease in at least one organ is called Hypereosinophilic Syndrome (HES).

GSK will sponsor this compassionate use trial of mepolizumab to treat subjects with HES who have significant clinical disease due to HES, are unresponsive to medication used to treat HES and those who have demonstrated clinical benefit with previous anti-IL-5 treatment.

The overall objective of this compassionate use supply program is to assess the safety and effectiveness of treatment with Mepolizumab in subjects with severe HES and subjects who previously benefited from anti-IL5 therapy.

Inclusion of a specific subject in this compassionate use supply program will be verified and approved by a GSK Medical Director or Clinician Committee based on the inclusion and exclusion criteria. After IRB/ethics committee approval is received, the investigator will complete a Subject Registration Form and send this to GSK via email or fax for review and approval of the subject’s eligibility. The Subject Registration Form will summarize the subject’s history of HES, current condition, previous HES therapies received and their outcome, and the rationale for inclusion in the compassionate use program.  Accrual of subjects will extend until mepolizumab receives regulatory approval and is commercially available.

Subjects will receive a supply of mepolizumab for up to monthly infusions with up to 10mg/kg (maximum dose 750 mg or 10mg/kg if body weight less than 45kg) mepolizumab IV for an initial three months of treatment. Increased duration and dose of treatment with mepolizumab will be determined based on the subject’s response to the initial three months of treatment as demonstrated by significant lowering of eosinophil level and/or decreased signs and symptoms of HES. Additional supplies of Mepolizumab will be shipped after GSK Medical Director receives and reviews the quarterly reports of subject progress and response to therapy. Clinical and laboratory assessments as per standard of care must be performed to evaluate disease response.

Contact Information
Monica Reiter-Wong
(212) 241-3092

Recruiting Patients: Yes