Merck’s Keytruda shrinks lung cancer tumors, FDA approval sought
{{#rendered}} {{/rendered}}Merck & Co Inc's Keytruda, approved for treating melanoma, was shown in a trial to shrink tumors in nearly half of advanced lung cancer patients with high levels of a protein used by tumors to evade the body's own disease-fighting cells.
The company said it has filed for U.S. Food and Drug Administration approval of the drug as a treatment for patients with non-small cell lung cancer (NSCLC) whose disease has worsened despite previous treatment.
Keytruda, also known as pembrolizumab, belongs to a new class of drugs designed to help the immune system fend off cancer by blocking a protein known as Programmed Death receptor (PD-1), or a related target known as PD-L1.
{{#rendered}} {{/rendered}}On Friday, Bristol-Myers Squibb Co said a trial of its PD-1 inhibitor, Opdivo, was stopped early after the drug proved to work better than chemotherapy in previously treated patients with non-squamous NSCLC. Opdivo is already approved for treating the less-common squamous NSCLC, as well as metastatic melanoma.
Merck said its FDA lung cancer filing is for patients with both squamous and non-squamous NSCLC.
Lung cancer, which kills nearly 160,000 Americans annually, is seen as the biggest opportunity for the PD-1 drugs, which analysts expect to reach billions of dollars in sales.
{{#rendered}} {{/rendered}}Merck's Phase 1 study of 495 patients with NSCLC, the most common form of the disease, found that 45 percent of patients with high levels of PD-L1 responded to Keytruda, compared with 16.5 percent of patients with PD-L1 levels of 1 percent to 49 percent.
For patients with PD-L1 below 1 percent, the response rate - defined as tumor shrinkage of at least 30 percent - was 10.7 percent.
Researchers said about a quarter of trial patients had PD-L1 expression in at least half of their tumor cells. Overall, 19 percent of trial patients responded to the drug.
{{#rendered}} {{/rendered}}Side effects of Keytruda included thyroid problems. One patient died from pneumonitis, or lung inflammation, which was seen in 3.6 percent of trial patients.
The Merck results were presented at a meeting of the American Association for Cancer Research and published in the New England Journal of Medicine.
Researchers also presented results from a trial showing that Keytruda improved the length of time before advanced skin cancer worsened by 42 percent and extended patient survival by 34 percent compared with treatment with ipilimumab, a different immunotherapy sold by Bristol-Myers under the brand name Yervoy.