The US Food and Drug Administration has cleared Pfizer’s Sutent for adjuvant treatment of adults at a high risk of their kidney cancer returning after a kidney has been removed.

Sutent (sunitinib), a kinase inhibitor that works by blocking several enzymes that promote cell growth, was first approved in 2006 for the treatment of certain patients with gastrointestinal stromal tumors and advanced renal cell carcinoma, and is also used to treat a certain type of pancreatic cancer.

Its approval for the adjuvant treatment of renal cell carcinoma was based on a randomised trial of 615 patients with high risk of recurrent renal cell carcinoma following nephrectomy. After five years, 59.3 percent of patients treated with Sutent had not experienced cancer recurrence or death compared with 51.3 percent of those receiving placebo.

The current treatment approach for RCC patients is surgery followed by observation, which is suboptimal for patients at high risk of recurrence.

“This is the first adjuvant treatment approved for patients with renal cell carcinoma, which is significant because patients with this disease who have a nephrectomy are often at high risk of the cancer returning,” said Richard Pazdur, director of the FDA’s Oncology Center of Excellence and acting director of the Office of Hematology and Oncology Products in the FDA’s Center for Drug Evaluation and Research.

“Some patients who have undergone surgery for locally advanced RCC are at high risk of recurrence and often fear their disease returning,” said Daniel George, study investigator and medical oncologist at Duke University Medical Center. “This adjuvant therapy is the first-of-its-kind and a remarkable clinical development for these patients who before today, have been restricted to a wait and see approach.”

However, the drug does come with a boxed warning to alert healthcare professionals and patients about the risk of severe liver damage (hepatoxicity), which may result in liver failure or death. Other potential serious side effects include heart failure, heart attack, hypertension, metabolic abnormalities, and osteonecrosis.

The National Cancer Institute estimates around 63,990 patients will be diagnosed with kidney and renal cell pelvis cancer this year, and 14,440 will die of the disease.