The US Food and Drug Administration (FDA) has approved the use of GlaxoSmithKline’s (GSK) Nucala (mepolizumab) for the treatment of eosinophilic granulomatosis with polyangiitis (EGPA) in adults.

Formerly known as Churg-Strauss syndrome, EGPA is a rare autoimmune disease leading to inflammation in the wall of blood vessels.

Nucala is an interleukin-5 antagonist monoclonal antibody (IgG1 kappa) developed using recombinant DNA technology in Chinese hamster ovary cells and is said to be the first targeted treatment approved for EGPA.

It is given once in every four weeks as a subcutaneous injection to the upper arm, thigh or abdomen.

The firm received priority review and orphan drug designations for the supplemental biologics licence application (sBLA) submitted for mepolizumab to the FDA in June this year.

“This approval follows the positive results of the largest prospective treatment study conducted in EGPA to date, and now for the first time physicians have a targeted treatment option for this debilitating condition.”

GSK Global Respiratory Franchise senior vice-president and head Eric Dube said: “This approval follows the positive results of the largest prospective treatment study conducted in EGPA to date, and now for the first time physicians have a targeted treatment option for this debilitating condition.”

The FDA approval is based on the results obtained from the 52-week Phase III MIRRA clinical trial that evaluated 300mg of Nucala in 136 patients who were on stable daily oral corticosteroids (OCS) therapy.

Results showed favourable co-primary and six secondary endpoints with mepolizumab treatment.

Patients are reported to have demonstrated significantly greater accrued time in remission when compared to placebo.

The most common Nucala-related adverse reactions observed during the trials were headache, injection site reaction, back pain and fatigue.