by Dr. C.H. Weaver M.D. 8/2017
Results of a Phase III clinical trial indicate that the investigational drug vandetanib delays the progression of locally advanced or metastatic medullary thyroid cancer. These results were presented at the 2010 annual meeting of the American Society of Clinical Oncology.
Medullary thyroid cancers account for approximately 2-3% of all thyroid cancers. These cancers tend to have a somewhat worse prognosis than more common types of thyroid cancer and up to 25% of cases are thought to be hereditary. When possible, treatment involves surgery to remove the thyroid gland. Chemotherapy and radiation therapy have shown limited effectiveness.(1)
Vandetanib is a targeted therapy with several mechanisms of action. Among other things, it inhibits a protein known as RET that plays an important role in hereditary medullary thyroid cancer.
To explore the efficacy of vandetanib for the treatment of advanced medullary thyroid cancer, researchers conducted a Phase III clinical trial among 331 patients with locally advanced or metastatic cancer that could not be surgically removed. (2) Patients were assigned to receive either vandetanib or a placebo. Patients have now been followed for a median of two years.
- Patients treated with vandetanib had longer progression-free survival and a higher rate of response to treatment.
- Information about overall survival is not yet available.
- Side effects that were more common among patients treated with vandetanib included diarrhea, rash, nausea, high blood pressure, and headache.
These results suggest that targeted drugs may play an important role in the treatment of medullary thyroid cancers.
- National Cancer Institute. Genetics of medullary thyroid carcinoma (PDQ®). Last modified July 1, 2010.
- Wells SA, Robinson BG, Gagel RF et al. Vandetanib (VAN) in locally advanced or metastatic medullary thyroid cancer (MTC): A randomized, double-blind phase III trial (ZETA). Presented at the 2010 annual meeting of the American Society of Clinical Oncology. Chicago, IL, June 4-8, 2010. Abstract 5503.