GSK's mepolizumab meets endpoints in phase 3 study

GSK said its mepolizumab treatment met co-primary efficacy endpoints and all secondary endpoints in a double-blind, placebo-controlled study on patients who have a form of vasculitis.

Published in the New England Journal of Medicine, the study found patients treated with mepolizumab had a significantly greater accrued time in remission over the 52-week treatment period compared to placebo, with 28% achieving remission for at least 24 weeks versus 3% on placebo, GSK said.

In addition, a higher proportion of patients in the mepolizumab group were in remission at both weeks 36 and 48 compared to the placebo group (32% vs 3%).

The patients had a small blood vessel condition known as eosinophilic granulomatosis with polyangiitis (EGPA) - a rare disease characterised by widespread inflammation in the walls of small blood vessels which may affect multiple organ systems and be associated with fatigue, fever and weight loss.

Principal investigator and lead author of the study Dr. Michael E Wechsler said EGPA patients suffer from recurrent relapses that place these patients at greater risk of permanent tissue and organ damage.

"There are currently no therapies specifically approved for EGPA. While systemic corticosteroids form the cornerstone of EGPA treatment, they can be associated with significant side effects."

"In this study, mepolizumab met several important clinical goals in the treatment of EGPA: it increased accrued time in remission, reduced frequency of relapse and exacerbation, and enabled patients to reduce corticosteroid dose. These data confirm the potential of mepolizumab as a future treatment option for patients with this rare disease."

Results of the study will support GSK's plans to submit regulatory applications, expected later in 2017, the company said, adding that mepolizumab is not approved for use anywhere in the world for EGPA.