The British pharma giant is seeking approval for mepolizumab as an add-on treatment to inhaled corticosteroid-based maintenance treatment for reducing exacerbations in patients with COPD guided by blood eosinophil counts.
In a complete response letter (CRL), the FDA said that more clinical data was required to support the drug’s approval.
GSK said that it will work closely with the regulator to work out the next suitable steps for the supplementary biologics license application (sBLA) for mepolizumab.
The CRL from the FDA follows a decision taken in July by its Pulmonary Allergy Drugs Advisory Committee which voted against recommending the COPD drug for approval in the applied indication.
GSK then said that the committee had voted against mepolizumab on the basis of data presented which showed that the risk-benefit profile was not adequate to support its approval.
The committee also indicated that there was lack of substantial evidence of the efficacy although it agreed that there was adequate evidence of the safety of mepolizumab in the targeted patient population. It also suggested the company to come up with additional data to characterize the patient population that would be most likely to benefit from mepolizumab.
The GSK respiratory drug, which is a monoclonal antibody that targets IL-5, was first approved in 2015 in the US for treating severe eosinophilic asthma. In 2017, mepolizumab became the first drug to be approved by the FDA for Eosinophilic Granulomatosis with Polyangiitis (EGPA).
According to GSK, mepolizumab is believed to work by stopping IL-5 from binding to its receptor on the surface of eosinophils. Prevention of IL-5 binding in this way lowers blood eosinophils, said the British pharma company.
In another development, GSK last week said that it will lay off 650 employees in its US operations under a global restructuring strategy announced in July 2018.