US drugmaker Merck has gained Breakthrough Therapy Designation (BTD) from the US Food and Drug Administration (FDA) for Keytruda to treat patients with classical Hodgkin lymphoma (cHL). The designation is based on data from ongoing Phase 1 studies, which Roger Perlmutter, president of Merck Research Laboratories, said were quite promising.

Lymphoma is a type of blood cancer affecting the lymphatic system, which removes excess fluids from the body and produces immune cells. It is estimated that more than 8,500 people will be diagnosed with Hodgkin lymphoma this year in the US alone – cHL accounts for 95% of all cases.

This is the fourth breakthrough status granted for Keytruda – the others were for advanced melanoma, advanced non-small cell lung cancer and advanced colorectal cancer. Keytruda is a humanized monoclonal antibody that works by increasing the ability of the immune system to help detect and fight tumor cells.

Perlmutter said Merck has launched an ambitious clinical development program examining the efficacy of Keytruda in a broad range of solid and blood cancers.