Results of a study funded by the National Center for Complementary and Alternative Medicine (NCCAM) and the National Cancer Institute (NCI) indicate that adding powdered shark cartilage (Benefin®) to standard cancer therapy did not benefit patients with advanced breast or colorectal cancer. The study, a randomized, placebo-controlled, double-blind clinical trial, enrolled 88 patients and assessed overall survival, side effects and quality of life. The study results were published in the July 1, 2005, issue of the journal Cancer.
The researchers designed and carried out this study because laboratory and animal studies of some forms of shark cartilage had suggested anti-cancer properties, specifically, an ability to slow growth of new blood vessels critical to the growth of new tumors. Other studies are continuing with different preparations of shark cartilage and different cancers.
In this study, it was difficult for patients to follow the study protocol. All patients were to receive standard care for their cancer, then they were randomized to receive either the Benefin® shark cartilage product or an identical-smelling placebo. The study required participants to mix the powder with juice or water and drink it 3 to 4 times a day. Half of the patients in both groups stopped taking the study product after 1 month. Poor patient adherence, difficulty with enrolling the target of 600 patients, and the lack of apparent evidence of benefit of the product resulted in the decision to stop the study early.