FDA grants priority review of Nucala for patients with Hypereosinophilic Syndrome (HES)

GlaxoSmithKline plc (GSK) announced that the US Food and Drug Administration (FDA) has granted a priority review for the company’s application seeking approval of Nucala (mepolizumab) in the treatment of patients with Hypereosinophilic Syndrome (HES) in the US.

If approval is obtained, it would make Nucala the first targeted biologic treatment for patients with this rare and life-threatening disease caused by eosinophilic inflammation. Treatment options are currently limited for patients with HES.

FDA has also granted both Fast Track and Orphan Drug designations for the use of Nucala in HES. These designations are often given to treatments that have the potential to address a high unmet need in patients with rare diseases.

The application is based on positive results from a pivotal phase 3 study that met its primary endpoint, demonstrating a statistically significant result of fewer patients experiencing a HES flare or withdrawal from the study when treated with mepolizumab, compared to placebo, when added to standard of care. All secondary endpoints were statistically significant in favour of mepolizumab compared to placebo.

FDA has previously approved Nucala for use as an add-on maintenance therapy for severe eosinophilic asthma and for the treatment of eosinophilic granulomatosis with polyangiitis (EGPA). Nucala is currently being investigated in several other eosinophil-driven diseases. It is not yet approved for use in HES anywhere in the world.