NEW YORK (Reuters Health) – Vandetanib shows encouraging action against advanced and metastatic medullary thyroid carcinoma, researchers report in an October 24th on-line paper in the Journal of Clinical Oncology.
“The results of this Phase III clinical trial,” Dr. Samuel A. Wells, Jr told Reuters Health by email, “demonstrate the effectiveness of vandetanib… in the treatment of patients with advanced medullary thyroid carcinoma, an uncommon but aggressive malignancy.”
“Previously,” he added, “there had been no effective therapy for patients with advanced stages of this tumor, although there were infrequent reports of short term responses to chemotherapy. Based on the data from this clinical trial the U.S. Food and Drug Administration recently approved vandetanib for the treatment of patients with advanced medullary thyroid carcinoma.”
Dr. Wells of the National Cancer Institute, Bethesda, Maryland and colleagues studied 331 patients who were randomized to the agent or to placebo in a 2:1 ratio.
At the time of analysis, after a median follow-up of 24 months, 124 patients (37%) had progressed and 48 (15%) had died. A final survival analysis will take place when 50% of the patients have died.
Significant prolongation of progression-free survival was observed for patients receiving vandetanib (hazard ratio, 0.46). The median was 19.3 months in the placebo group and is predicted to be 30.5 months in the active treatment group. Progression-free survival at 6 months was seen in 83% of the vandetanib group and 63% of placebo patients.
Significant advantages for vandetanib were also seen for objective response rate, disease control rate and biochemical response.
Multiple adverse events occurred in more than 30% of patients receiving vandetanib and were more common than in the placebo group. Among such events were diarrhea (56% versus 26%), rash (45% versus 11%) and hypertension (32% versus 5%).
Dr. Wells added that “Molecular targeted therapeutics, such as vandetanib, have shown efficacy, not only in the treatment of the more common types of thyroid cancer, but in certain other solid tumor malignancies, as well as leukemia. Molecular targeted therapeutics represent a new and significant advance in cancer therapy.”
“I think,” he concluded, “that it fair to say that vandetanib is the standard of care for patients with advanced medullary thyroid carcinoma.”
Commenting on the findings, Dr. Benjamin Solomon, co-author of an accompanying editorial agreed, telling Reuters Health in an email that “This phase III study establishes vandetanib as an appropriate standard in patients with locally advanced or metastatic medullary thyroid cancer.”
However, “Treatment with vandetanib is associated with some toxicity and the impact of vandetanib on quality of life is not clear from this study.”
Dr. Solomon of the Peter MacCallum Cancer Centre, East Melbourne, Australia concluded that “Treatment with vandetanib is most appropriate for patients who are symptomatic, have high disease burdens or rapidly progressing disease while those with asymptomatic or slowly progressing patients and low disease burden may be more appropriately monitored off therapy with careful assessment of the tempo of disease progression.”
J Clin Oncol 2011.
