New Drug May Slow Advanced Ovarian Cancer
Study found it prolonged remission after chemotherapy almost six months longer than a placebo
No targeted therapies are currently approved in the United States for maintenance treatment of ovarian cancer.
Pazopanib, which is taken in pill form, works by blocking the growth of tumors and their blood vessels. The U.S. Food and Drug Administration has already approved its use for the treatment of kidney cancer and soft tissue sarcoma. The drug's maker, GlaxoSmithKline, funded this latest research.
In the study, 940 patients with stage III or IV ovarian cancer received either pazopanib or a placebo daily for 24 months. All patients already had gone through surgery and chemotherapy that successfully prevented the disease from worsening.
Researchers found that the pazopanib group experienced a median 17.9 months before their cancer symptoms returned, compared with 12.3 months for patients taking the placebo.
There are drawbacks. For one, Votrient is a costly drug. Online pharmacies charge around $1,900 for 30 200-milligram tablets of the medication.
Also, one of every four ovarian cancer patients taking pazopanib reported unpleasant side effects, including hypertension, diarrhea, nausea, headache and fatigue.
"If they were having horrible diarrhea or nausea while they were on it, that five months will look a lot less attractive than if there were minimal side effects," Lu noted.
Lichtenfeld said more research is needed to determine if maintenance treatment with pazopanib will improve overall survival. Researchers also need to look into whether using pazopanib alongside chemotherapy will produce even better results.
"We just don't know if this is going to translate into a meaningful improvement of survival for these women," he said. "We really have to be cautious in determining where that new treatment fits in the overall care for these women. This may be very exciting, but we need more time and analysis to see how this fits in the treatment protocols we would use for women treated in more routine settings than a clinical trial."
Research also needs to determine whether there are certain types of patients who would respond more favorably to pazopanib, Lu added.
"Can we identify a subgroup of patients who will have a good response and will have a prolonged period where they can be off of chemotherapy?" she said. "For all biologic agents, that's an important area of research, to identify markers that will tell us which patients will have that benefit."