AstraZeneca gains FDA approval for medullary thyroid cancer drug
SILVER SPRING, Md.óAstraZeneca Pharmaceuticals LP announced today that they have secured U.S. Food and Drug Administration (FDA) approval for the drug vandetanib for the treatment of adult patients suffering from late-stage (metastatic) medullary thyroid cancer whose disease is growing and who are ineligible for surgery. This is the first such drug with FDA approval for treating medullary thyroid cancer.
Thyroid cancer consists of cancerous growths of the thyroid gland, the small organ at the base of the throat that produces the hormones responsible for regulating such things as heart rate, body temperature, blood pressure and weight. There are four main types of thyroid cancer: papillary, follicular, medullary and anaplastic. Medullary thyroid cancer involves the parafollicular calcitonin-secreting cells located in the thyroid gland, and it can either occur spontaneously or be a component of a genetic syndrome.
According to the National Cancer Institute, there were approximately 44,670 new cases of thyroid cancer diagnosed in the United States in 2010, and approximately 1,690 people died from thyroid cancer. Of those cancer diagnoses, 2 percent to 3 percent are medullary thyroid cancer. The average survival rate for medullary thyroid cancer is lower than that of the more common kinds of thyroid cancer, as there is generally an 83 percent five-year survival for medullary thyroid cancer compared to a 90 percent to 94 percent five-year survival for papillary or follicular thyroid cancer.
The most common symptoms of medullary thyroid cancer include enlargement of the thyroid gland, coughing, difficulty swallowing, hoarseness or changes in a person's voice, swelling of the neck and a lump on the thyroid.
"Vandetanib's approval underscores FDA's commitment to approving treatments for patients with rare and difficult to treat diseases," says Richard Pazdur, M.D., director of the Office of Oncology Drug Products in the FDA's Center for Drug Evaluation and Research.
Vandetanib was studied in a randomized trial of 331 patients with late-stage medullary thyroid cancer in order to study the safety and efficacy of the drug and to determine the length of time that patients lived without their cancer progressing (progression-free survival). Patients in the study received either vandetanib or a placebo, and those who received vandetanib experienced longer periods of time without disease progression compared to the patients who received the placebo sugar pill. The median progression-free survival for those who received the placebo was 16.4 months and at least 22.6 months for those who received the vandetanib.
Vandetanib is taken daily and is administered orally, and works by targeting medullary thyroid cancer's ability to grow. Common side effects of the drug include rash, nausea, headache, diarrhea, fatigue, stomach (abdominal pain), decreased appetite and high blood pressure. Serious side effects were reported during the study and resulted in five deaths of patients taking vandetanib. Heart failure, breathing complications and a bacterial blood infection (sepsis) were the reported causes of death. Vandetanib was shown to have an effect on the electrical activity of the heart, which can cause irregular heartbeats and possibly lead to death. As such, it is being approved with a Risk Evaluation and Mitigation Strategy (REMS).
AstraZeneca is marketing vandetanib, though no trade name has been established for the drug as of yet.