Mepolizumab As a Steroid-sparing Treatment Option in the Churg Strauss Syndrome

Phase 1

Completed

Brief Summary: The purpose of this study is to determine whether Mepolizumab (a monoclonal antibody against interleukin-5) is a safe and well-tolerated therapy that will allow for steroid tapering in patients with steroid-dependent Churg-Strauss Syndrome (CSS).

Detailed Description: Specific Aims:

1. Document the safety of mepolizumab therapy in patients with CSS.

2. Demonstrate the steroid sparing effect of mepolizumab therapy by decreasing corticosteroid dosage while using this anti-IL5 therapy.

3. Demonstrate the efficacy of anti-IL5 therapy in improving the signs and symptoms of CSS by:

1. Measuring serum markers of CSS disease activity, including: peripheral eosinophilia, erythrocyte sedimentation rate, anti- neutrophil cytoplasmic antigen, C-reactive protein and IgE levels.

2. Assessing the activity level of vasculitis via the Birmingham Vasculitis Activity Score

3. Evaluating asthmatic response via serial peak flow and FEV1 measurements as well as asthma symptom scores using the Juniper scale.

4. Assessing changes in novel parameters such as fractional excretion of nitric oxide and IL-5 levels.

Recruitment & Eligibility

Inclusion Criteria

Age >18 years old
Diagnosis of Churg Strauss Syndrome
Maintained on stable corticosteroid dose of at least prednisone 10mg daily (or equivalent) prior to enrollment in study
If on cyclophosphamide, azathioprine or methotrexate, must be on a stable dose and be able to maintain that dose for the duration of the study

Exclusion Criteria

Hypereosinophilic Syndrome
Wegener's Granulomatosis
Malignancy
Parasitic Disease
Pregnant or nursing
If female and of child-bearing potential, must have negative pregnancy test prior to each infusion of study medication and must adhere to acceptable method of contraception (with <1% failure rate)
Any other medical illness that precludes study involvement

Arm && Interventions

Group	Intervention	Description
Mepolizumab	Mepolizumab	Subjects will receive open-label mepolizumab

Primary Outcome Measures

Name	Time	Method
Number of Participants With Indicated Side Effects	Participants were followed for the duration of the study, approximately 44 weeks	Side effects experienced by participants 1 to 2 days after Mepolizumab infusion.
Number of Participants Who Experienced Specific Symptoms	44 weeks	Number of participants who experienced specific symptoms during the trial.

Secondary Outcome Measures

Name	Time	Method
Steroid Dosing During Trial	20 weeks
Evaluate Overall Positive Change in Churg-Strauss Syndrome Via the Measures Outlined in Study Aims	20 weeks	The Asthma Control Questionnaire (ACQ) was one measure used to assess the prevalence of asthma symptoms the participant was having during the study. It is a series of 7 questions assessing how often, over the past two weeks, the participant wakes up from their asthma, how bad their symptoms were, etc. The greater the prevalence of symptoms, the higher the score. Each of the 7 questions is scored 0-6. The total score is calculated by adding the individual question scores and dividing the sum by 7.
Efficacy- Exacerbation Rate	Treatment period (12 weeks)	Quantified the exacerbation rate (total number of exacerbations per day) of the participants during treatment with mepolizumab and without treatment. Exacerbations were characterized as any worsening of clinical disease requiring an increase of systemic corticosteroid therapy (e.g. prednisone) for asthma, respiratory symptoms, or underlying vasculitis.