The kidney and liver cancer drug sorafenib (Nexavar) holds metastatic thyroid cancer at bay nearly twice as long as placebo, according to the results of the randomized phase III trial known as DECISION. These results were presented at the 2013 annual meeting of the American Society of Clinical Oncology in early June in Chicago, Illinois.
If approved for use in patients with thyroid cancer by the FDA, sorafenib, a kinase inhibitor that mediates tumor cell division and growth of tumor blood vessels, would be the first effective agent for this patient population. Thyroid cancer is highly curable through surgery and radioactive iodine treatment, but approximately 10% of the 60,000 patients in whom the disease is diagnosed each year fail to respond to standard therapies, with tumors eventually appearing in the lymph nodes, bones, lungs, and other sites. The only other drug for advanced thyroid cancer, doxorubicin, which was approved in 1974, is not used because it is highly toxic and is not effective.
“Until we began using sorafenib, we had no medical options for these patients who suffered due to progression of their disease,” said principal investigator Marcia S. Brose, MD, PhD, an assistant professor of Otolaryngology and Head and Neck Surgery and Hematology/Oncology at the University of Pennsylvania School of Medicine in Philadelphia. “Now, we can give patients hope—a breakthrough medication that can stop the progression of the disease for 5 months. This trial is the first step in a promising series of clinical trials to identify new drugs that are shifting the horizon for patients with advanced thyroid cancer.”
Of the 417 metastatic thyroid cancer patients studied in the multicenter, international trial, 207 were randomized to receive the oral drug sorafenib and 210 to receive a placebo. A total of 12% of the patients in the sorafenib arm experienced tumor shrinkage, compared to 0.5% of patients taking a placebo. Importantly, the therapy also appeared to thwart disease progression even among many of those whose tumors did not regress: 42 patients who took sorafenib had stable disease after 6 months, compared to 33% of those in the placebo group.
Among patients taking sorafenib, median progression-free survival was 10.8 months, compared to 5.8 months among the placebo group. Patients taking the placebo were allowed to cross over into the sorafenib arm once their disease progressed; 70% of them did so. Overall survival data is not yet available.
The most common adverse events observed among patients taking sorafenib included hand-foot skin reaction, diarrhea, alopecia, rash, fatigue, weight loss, and hypertension. These are all consistent with findings from previous trials of the drug for its approved indications.