GlaxoSmithKline (GSK) has initiated a Phase III trial of an investigational IL-5 antagonist mepolizumab for the treatment of patients with eosinophilic granulomatosis with polyangiitis (EGPA), previously known as Churg-Strauss syndrome.
EGPA is characterised by widespread inflammation in the walls of small blood vessels (vasculitis). It can affect multiple organs, including the heart, lungs, skin, gastrointestinal tract, kidneys, and nervous system, with varying symptoms.
The main goal in the treatment of the disease, which can be life-threatening for some patients, is to induce and maintain remission, while reducing the use of corticosteroids and other immunosuppressive therapies.
The Phase III study, MEA115921, is designed to evaluate the efficacy and safety of a 300mg dose of mepolizumab given every 4 weeks compared with placebo over a 52-week study treatment period in patients with relapsing or refractory EGPA receiving standard of care therapy including background corticosteroid therapy with or without immunosuppressive therapy.
It is a randomised, double-blind trial that is being carried out as part of a deal between GSK and the National Institute of Allergy and Infectious Diseases (NIAID), part of the US National Institutes of Health, under which the mechanisms that underlie EGPA will also be investigated, with potential future benefits for patients.
GSK disease area head Richard Philipson said: "There are currently limited treatment options for patients with EGPA and our plan to start this Phase III study was achieved in collaboration with the NIAID."
In the US and five European countries, around 4,300 people are affected with EGPA, which is one of the rarest systemic vasculitic (inflammation of blood vessel walls) diseases.
The company said that symptoms of EGPA differ from one patient to another, while almost all have asthma or nasal sinus polyps and blood eosinophilia.
The existing approach to disease management is mainly based on reduction of active inflammation and suppression of the immune response through the use of corticosteroid therapy with concomitant immunosuppressive therapy.
Mepolizumab is an investigational fully humanised IgG monoclonal antibody specific for interleukin 5 (IL-5) being developed for diseases, which include EGPA, severe asthma with eosinophilic inflammation, hypereosinophilic syndrome, eosinophilic esophagitis and nasal polyposis.