The US Food and Drug Administration (FDA) has approved GlaxoSmithKline (GSK)’s Blenrep (belantamab mafodotin-blmf) as monotherapy to treat relapsed or refractory multiple myeloma.

Blenrep is the first anti-B-cell maturation antigen (BCMA) drug approved globally. It obtained breakthrough therapy designation from the FDA in 2017.

The drug is for use in adults who had at least four previous therapies, including an anti-CD38 monoclonal antibody, a proteasome inhibitor and an immunomodulatory agent.

GSK said that the FDA granted authorisation under accelerated approval based on response rate; continued approval may come from data from confirmatory trials.

GSK chief scientific officer and R&D president Dr Hal Barron said: “As the second most common form of blood cancer in the US, multiple myeloma is an incurable and devastating disease.

“Blenrep is the first approved anti-BCMA therapy and has the potential to transform the treatment of patients with relapsed or refractory myeloma who have limited treatment options today.’’

The drug exhibits a multi-faceted mechanism of action and targets BCMA, a cell-surface protein involved in the plasma cells survival and expressed on multiple myeloma cells.

FDA approved the drug based on six-month primary data from the pivotal DREAMM-2 clinical trial performed in patients with relapsed or refractory multiple myeloma that actively progressed and worsened even after the current standard of care.

Results showed that a 2.5mg kg every three weeks dose of the drug led to a clinically meaningful overall response rate (ORR) of 31% in participants who received at least seven lines of treatment previously.

Though the median duration of response (DoR) had not been reached at the six-month analysis, 73% of responders were found to have achieved a DoR equal to or greater than six months.

In June, the company received Japan’s Ministry of Health, Labour and Welfare approval for Duvroq (daprodustat) to treat anaemia caused by chronic kidney disease (CKD).