The U.S. Food and Drug Administration has expanded the approved uses of Nexavar (sorafenib) to treat late-stage, metastatic differentiated thyroid cancer. The drug works by inhibiting multiple proteins in cancer cells to limit their growth and division. The drug's new use is intended for patients with locally recurrent or metastatic, progressive differentiated thyroid cancer that no longer responds to radioactive iodine treatment.
“Differentiated thyroid cancer can be challenging to treat, especially when unresponsive to conventional therapies,” Richard Pazdur, MD, Director of the Office of Hematology and Oncology Products in the FDA's Center for Drug Evaluation and Research, said in a news release. “This approval demonstrates the FDA's commitment to expediting the availability of treatment options for patients with difficult-to-treat diseases.”
The FDA completed its review of Nexavar's new indication under its priority review program, which provides for an expedited, six-month review for drugs that may offer a significant improvement in safety or effectiveness of the treatment, prevention or diagnosis of a serious condition (OT 9/25/13). Nexavar also received Orphan Product Designation by the FDA because it is intended to treat a rare disease or condition. Approximately 60,220 Americans will have been diagnosed with the disease this year, according to National Cancer Institute estimates.
Safety and effectiveness were established in a clinical study of 417 patients with locally recurrent or metastatic, progressive differentiated thyroid cancer that was not responding to radioactive iodine treatment. Nexavar was shown to increase progression-free survival by 41 percent: Half of the patients receiving Nexavar had progression-free survival of 10.8 months compared with 5.8 months for patients receiving a placebo.
The most common side effects associated with the drug were diarrhea, fatigue, infection, alopecia, hand-foot skin reaction, rash, weight loss, decreased appetite, nausea, gastrointestinal and abdominal pains, and hypertension. It was also noted that thyroid-stimulating hormone, a potential promoter of thyroid cancer, is more likely to become elevated while patients are on treatment with Nexavar, requiring adjustment of thyroid hormone replacement therapy.
Nexavar was approved to treat advanced kidney cancer in 2005 (OT 2/25/06), and the FDA expanded the drug's label to treat liver cancer that cannot be surgically removed in 2007.
Nexavar is co-marketed by Bayer HealthCare Pharmaceuticals Inc. and Onyx Pharmaceuticals.