Approval for biomarker-based Keytruda a US FDA first

The US Food and Drug Administration (FDA) granted accelerated approval to Merck & Co.’s Keytruda indication, which is intended for patients whose cancers have a specific genetic feature, or biomarker.

“Until now, the FDA has approved cancer treatments based on where in the body the cancer started – for example, lung or breast cancers. We have now approved a drug based on a tumour’s biomarker without regard to the tumour’s original location,”​ said FDA acting director of the Office of Hematology and Oncology Products, Richard Pazdur.

The indication is designed for patients with solid tumours that have progressed following prior treatment, and lack alternative treatment options, as well as patients with colorectal cancer that has progressed despite undertaking chemotherapy treatments.

Merck says the decision may alter FDA approval processes in the future.

The decision “represents an important advance in the use of biomarkers to guide clinical decision-making and changes the paradigm for how cancer drugs may get approved moving forward,” ​said Merck’s Pamela Eisele told in-PharmaTechnologist.

Merck is confident it will be able to continue to meet demand, she added.

Keytruda ​

Monoclonal antibody Keytruda (pembrolizumab) is indicated for the treatment of adult and paediatric patients with unresectable or metastatic solid tumours with an identified microsatellite instability-high (MSI-H) or mismatch repair deficient (dMMR) biomarker.

Tumours with these biomarkers are most commonly found in colorectal, gastrointestinal, and endometrial cancers.

Keytruda, administered as a 100mg injection, targets proteins found on the body’s immune cells and some cancer cells, and consequently blocks the cellular pathway.

“By blocking this pathway, Keytruda may help the body’s immune system fight the cancer cells,” ​said the US FDA.

“Further study is required to verify and describe anticipated clinical benefits of Keytruda, and the sponsor is currently conducting these studies in additional patients with MSI-H or dMMR tumours,” ​said the US FDA.

Keytruda indications previously approved by the FDA include the treatment of certain patients with metastatic melanoma, metastatic non-small cell lung cancer, recurrent or metastatic head and neck cancer, refractory classical Hodgkin lymphoma, and urothelial carcinoma.