New Melanoma Drug May Extend Survival
However, patients typically still got worse after only a few months on the drug.
The drug, called dabrafenib, blocks a signaling protein and is used to treat melanomas with a specific genetic mutation. About half of melanoma patients have this mutation.
In a phase 3 trial funded by the drug's maker, GlaxoSmithKline, an international group of researchers led by Dr. Axel Hauschild of the Schleswig-Holstein University Hospital in Kiel, Germany, gave dabrafenib or the most common existing treatment, dacarbazine (DTIC-Dome), to 250 patients with spreading or inoperable melanoma. About half responded partially (47 percent) or fully (3 percent) to dabrafenib; the response rate among the dacarbazine group was just 6 percent.
Those who took the new drug survived for an average of 5.1 months without getting worse; 2.7 percent of those treated with the existing drug did the same.
The study authors report that the new drug had few side effects, and those related to the skin appeared to be less severe than in patients on a similar drug called vemurafenib (Zelboraf). That drug is now available in the United States.
It's not clear if the drug will affect overall survival rates. "This trial is good news for our patients with metastatic melanoma. Competition in the field is appreciated since it accelerates new clinical trials, particularly in the combinational setting," Hauschild said in a news release from The Lancet, which published the study online June 25.
"This trial is a major step forward in the run for an improvement of the survival for this disease, which was thought to be untreatable for decades," he added.
Dr. Vernon K. Sondak, chair of the department of cutaneous oncology at the Moffitt Cancer Center in Tampa, said treatments for melanoma have been lacking. New so-called "targeted" drugs like dabrafenib have shown promise, he added, "but all these targeted therapies have a weakness, and that is the eventual development of resistance in the tumor cells."
Still, the research into various drugs "opens up new possibilities for combination therapies that may be even more effective, potentially without causing increased side effects," he said.
As for cost, Sondak said melanoma treatments have been so expensive that health agencies in some countries have refused to pay for them.
For more about melanoma, try the U.S. National Library of Medicine.
Posted: June 2012