- The Food and Drug Administration has approved Merck & Co.'s immunotherapy Keytruda for use in early kidney cancer, making it the first treatment of its type available to patients whose renal cell carcinoma tumors haven't yet spread widely.
- Keytruda's clearance covers so-called adjuvant use — after surgery to remove a kidney or metastatic lesions — for patients who are at intermediate or high risk of their cancer recurring. In the main study supporting its approval, Keytruda reduced the chance of cancer's return, spread or death by 32% compared to a placebo.
- The decision is another example of how immunotherapy drugs, first introduced for treating metastatic tumors, are now being moved into earlier lines of cancer care. But the study results supporting these approvals often are too early to prove treatment extends lives, adding to debate about the extent of the drugs' benefits.
Approval of Keytruda in this setting comes about six months after Merck revealed early results from a study called Keynote-564, which showed the immunotherapy could help keep kidney cancers in remission for longer.
The benefit was assessed on a measure known as disease-free survival, or the time until a patient dies or their cancer recurs or metastasizes. As patients are being treated early, when their tumors are still small or local enough to be removed surgically, they typically live for much longer than when tumors are already advanced or metastatic. That means studies must run for longer to prove drugs being tested actually extend patient's lives, rather than just lengthening the amount of time in remission.
Measuring disease-free survival gives drugmakers a chance to show their drugs have an effect earlier, although the endpoint is criticized by some for overselling a treatment's benefit.
When Keynote-564 was reviewed to assess Keytruda's benefit on disease-free survival, only 5% of the study's nearly 1,000 participants had died, too few to make any determinations about whether the drug extended overall survival, too. The trial will continue to assess overall survival, Merck said in a statement on the FDA's approval Thursday.
Merck and other drugmakers like Bristol Myers Squibb and Roche are also studying their immunotherapies as adjuvant treatments for other cancer types like skin, lung and breast tumors. Already top-sellers, the drugs could become even more lucrative for their makers should they be adopted widely alongside surgery.
While Keytruda is the first in kidney cancer, results are also expected from studies of Roche's Tecentriq, Bristol Myers' Opdivo and AstraZeneca's Imfinzi.
The FDA approved Keytruda for this setting under priority review, which expedites the regulator's evaluation.