Beyond EOsinophils: proteoMICS to Identify Potential Biomarker of Organ Damage and Response to MEPOLIZUMAB in EGPA

Beyond Eosinophils: Proteomics to Identify Potential Biomarkers of Organ Damage and Response to MEPOLIZUMAB in EGPA

Aim of the study is to identify potential biomarkers, through a proteomic approach, which could be used to evaluate organ damage and predict the response to mepolizumab in a cohort of patients affected by EGPA. Proteomic analyses will be performed using a proteomic platform, based on a nano-HPLC- couplet to an high resolution ESI-MS device, on three types of biological matrices: blood, saliva and sputum samples in both EGPA and severe asthmatic patients (as controls) at baseline and at different time points after starting treatment with mepolizumab, an anti-IL-5 drug, in order to cluster patients and to analyze the effect of the therapy during treatment, assessing the disease progression on three key aspects: lung function and symptoms control, vasculitis and neuropathy. Plasma analysis will provide an overview of quantitative/qualitative proteomic variations at systemic level after drug administration; however, a less invasive procedure is often sufficient and would improve trial recruitment. On this regard, saliva is a biological fluid well suitable to be used in proteomic investigations for suggestion of potential disease biomarkers and includes various potential advantages compared with blood sample collection such as lower overall cost, lower infection risk, increased patient convenience, acceptability, compliance and uptake. Moreover, the protein composition of the human saliva includes both specific proteins of the oral cavity and proteins common to other tissues and bodily fluids, so saliva prognostic and diagnostic role is particularly interesting. Consequently, the plan is to compare the proteomic results of the non-invasive saliva testing to that of blood examination.

These data may be a further step to untangle the mechanisms of the disease and to characterize treatment's response, in the contest of a phenotype/endotype asthma management.

The investigators plan to collect blood, salivary and sputum samples in both EGPA and severe asthmatic patients (as controls) at baseline and at different timepoints after starting treatment with mepolizumab, an anti-IL-5 drug, in order to cluster patients and to analyse the effect of the therapy during treatment and assess the disease progression on three key aspects of the disease: lung function and symptoms control, vasculitis and neuropathy.

untangle the mechanisms of the disease and to characterize response to treatment, in the context of a phenotype/endotype asthma and EGPA management.

Inclusion Criteria:

• Informed Consent: Prior to start any study related activities, participants must be able and willing to provide written informed consent;
• Participants must have a current clinical diagnosis of asthma or EGPA;
• Physician decision to initiate treatment with mepolizumab.
• Patient has to be in treatment with medium-high dose ICS plus an additional controller in the least 6 months before screening and, if on OCS therapy, a stable dosage of prednisone (or equivalent dose of other steroids) in the 4 weeks before screening will be allowed. The above-indicated treatment has to be maintained by the patient all along the study.
• Adults aged 18 years or over.

Exclusion Criteria:

• Asthmatic patients receiving other biological treatment
• Participation in an interventional clinical trial in which the treatment regimen and/or monitoring is dictated by a protocol during the previous 12 months.
• Pregnant and breastfeeding woman