FDA clears Merck's Keytruda for cancers with certain genetic traits

Posted May 25, 2017

The drug, a humanised monoclonal antibody that blocks the interaction between PD-1 and its ligands, thereby activating T lymphocytes, is already approved in the USA for indications within melanoma, lung cancer, head and neck cancer and classical Hodgkin lymphoma (cHL).

Merck & Co has won an accelerated approval from the U.S. Food and Drug Administration for its cancer drug Keytruda Tuesday, a treatment for patients whose cancers have a specific genetic feature. Pembrolizumab is created to target the PD-1/PD-L1 cellular pathway to help the body's own immune system fight cancer cells.

The drug is now indicated for adult and pediatric patients with unresectable or metastatic microsatellite instability-high or mismatch fix deficient solid tumors that lack suitable alternative treatments or that have progressed on treatment. The indication applies to patients with solid tumors who have progressed following prior treatment and have no viable alternative treatment options and patients with colorectal cancer (CRC) who have progressed after certain chemotherapy. The ORR was 36% in patients with CRC and 46% in patients with other tumor types. Ninety patients had colorectal cancer (CRC) and the remaining 59 patients had 1 of 14 other tumor types. "For 78 percent of those patients, the response lasted for six months or more", the FDA said.

MSI-high or MMR-deficient tumors are most commonly found in endometrial cancer, colorectal cancer (up to 5% of metastatic patients), and other gastrointestinal cancers.

Massive landslide leaves 14000 pilgrims stuck on Badrinath highway
Chief Minister Trivendra Singh Rawat has instructed Secretary Amit Negi to constantly monitor the situation. "The road will be opened for the traffic by this afternoon today", a district official said.

Common adverse events due to pembrolizumab included constipation, cough, decreased appetite, diarrhea, dyspnea, fatigue, musculoskeletal pain, nausea, pruritus, pyrexia, and rash.

Keytruda is administered as an intravenous infusion over 30 minutes every three weeks for the approved indications.

In a groundbreaking approval, the FDA has paved the way for the country's first cancer medication that isn't targeted at only one part of the body. Just this year, the drug has secured approval as a first-line treatment for metastatic, non-squamous non-small cell lung cancer (NSCLC) regardless of PD-L1 expression, as a first-line and second-line medicine for some cases of locally advanced or metastatic urothelial carcinoma, and as a medication for refractory classical Hodgkin lymphoma. Keytruda can cause serious conditions known as immune-mediated side effects, including inflammation of healthy organs such as the lungs (pneumonitis), colon (colitis), liver (hepatitis), endocrine glands (endocrinopathies) and kidneys (nephritis). The safety and effectiveness of Keytruda in pediatric patients with MSI-H central nervous system cancers have not been established.

The accelerated approval for Keytruda in this setting is contingent on the results of a confirmatory trial.