WASHINGTON (AP) ― Patients with hard-to-treat kidney cancer that has spread to other parts of the body gained a new drug option Friday, after federal regulators approved a twice-a-day pill from Pfizer for the disease.

The Food and Drug Administration approved the company’s drug Inlyta as a secondary option for patients with renal cell carcinoma that hasn’t responded to previous drug treatments. Renal cell carcinoma is the most common form of kidney cancer, with an estimated 61,000 people in the U.S. newly diagnosed last year, according to the National Cancer Institute. Only about 11 percent of patients with advanced kidney cancer survive five years or more after diagnosis.

Like other recent cancer drugs, Inlyta works by blocking proteins that promote tumor growth and cancer progression.

The market for kidney cancer drugs has grown increasingly crowded in recent years, with six other new drugs approved in the last six years, including Roche’s Avastin and GlaxoSmithKline’s Votrient. Pfizer’s drug is only the second to be designated as a backup, or second-line, treatment after other kidney cancer drugs have been prescribed. Pfizer is also conducting studies of the drug as a first-line option against kidney cancer.

“This is the seventh drug that has been approved for the treatment of metastatic or advanced kidney cell cancer since 2005,” said Dr. Richard Pazdur, FDA’s cancer drug director, in a statement. “Collectively, this unprecedented level of drug development within this time period has significantly altered the treatment paradigm.”

The FDA approved the drug based on a single study in which patients on Inlyta, known chemically as axitinib, experienced two more months without their cancer worsening than patients taking Nexavar, a drug from Bayer and Onyx Pharmaceuticals.

The most common side effects with Inlyta included diarrhea, high blood pressure, fatigue, nausea, weight loss and decreased appetite, among others.

About 13,000 people in the U.S. die of advanced kidney cancer each year, according to the American Cancer Society.

“Even with the advent of targeted therapies, the need remains for additional options for patients with advanced renal cell carcinoma whose disease has progressed following first-line medications,” Pfizer Senior Vice President Dr. Mace Rothenberg said in a statement.

Shares of New York-based Pfizer Inc. fell 12 cents to $21.51 in afternoon trading.