The US Food and Drug Administration (FDA) have approved Nexavar (sorafenib) to treat some people with advanced thyroid cancer. The drug was already on the market for treating some types of kidney cancer and liver cancer. The new approval is for treating differentiated thyroid cancer – the most common type – that has come back after treatment or that has spread to other parts of the body (metastasized), and is no longer responding to radioactive iodine treatment.
Thyroid cancer starts in the thyroid gland, which is located in the front part of the neck. Nexavar is a targeted therapy that can help stop the growth of cancer cells by interfering with signals that encourage them to grow. Nexavar qualified for faster review under the FDA’s priority review program for drugs that may offer a significant improvement in safety or effectiveness of the treatment, prevention, or diagnosis of a serious condition. The drug also received orphan-product designation by the FDA because it is intended to treat a rare disease or condition.
“Differentiated thyroid cancer can be challenging to treat, especially when unresponsive to conventional therapies,” said Richard Pazdur, MD, director of the Office of Hematology and Oncology Products in the FDA’s Center for Drug Evaluation and Research, in a prepared statement. “Today’s approval demonstrates the FDA’s commitment to expediting the availability of treatment options for patients with difficult-to-treat diseases.”
The FDA based its approval on a clinical study involving 417 people with advanced, differentiated thyroid cancer that was not responding to radioactive iodine treatment. Nexavar increased the length of time patients lived without the cancer growing by 41%. Half the people who received Nexavar lived without the cancer growing for at least 10.8 months compared to at least 5.8 months for those who received a placebo.
The most common side effects for Nexavar were diarrhea, fatigue, infection, hair loss, skin problems on the hands and feet, rash, weight loss, decreased appetite, nausea, gastrointestinal and abdominal pains, and high blood pressure. Thyroid stimulating hormone is more likely to become elevated while on treatment with Nexavar, requiring adjustment of thyroid hormone therapy.
Nexavar is co-marketed by Bayer HealthCare Pharmaceuticals Inc. and Onyx Pharmaceuticals.