The use of vitamin E for the prevention of chemotherapy-induced peripheral neuropathy: results of a randomized phase III clinical trial.

BACKGROUND: Chemotherapy-induced peripheral neuropathy (CIPN) continues to be a substantial problem for many cancer patients. Pursuant to promising appearing pilot data, the current study evaluated the use of vitamin E for the prevention of CIPN. METHODS: A phase III, randomized, double-blind, placebo-controlled study was conducted in patients undergoing therapy with neurotoxic chemotherapy, utilizing twice daily dosing of vitamin E (400 mg)/placebo. The primary endpoint was the incidence of grade 2+ sensory neuropathy (SN) toxicity (CTCAE v 3.0) in each treatment arm, analyzed by chi-square testing. Planned sample size was 100 patients per arm to provide 80% power to detect a difference in incidence of grade 2+ SN toxicity from 25% in the placebo group to 10% in the vitamin E group. RESULTS: Two-hundred seven patients were enrolled between December 1, 2006 and December 14, 2007, producing 189 evaluable cases for analysis. Cytotoxic agents included taxanes (109), cisplatin (8), carboplatin (2), oxaliplatin (50), or combination (20). There was no difference in the incidence of grade 2+ SN between the two arms (34%-vitamin E, 29%-placebo; P = 0.43). There were no significant differences between treatment arms for time to onset of neuropathy (P = 0.58), for chemotherapy dose reductions due to neuropathy (P = 0.21), or for secondary endpoints derived from patient-reported neuropathy symptom assessments. The treatment was well tolerated overall. CONCLUSIONS: Vitamin E did not appear to reduce the incidence of sensory neuropathy in the studied group of patients receiving neurotoxic chemotherapy.

Evaluation of shark cartilage in patients with advanced cancer: a North Central Cancer Treatment Group trial.

BACKGROUND: Shark cartilage has been a popular complementary or alternative medicine intervention. The basis for this popularity is the claim that sharks rarely get cancer because of the high proportion of cartilage in the shark's body. However, early studies were equivocal. Therefore, a clinical trial was conducted to look at the impact of shark cartilage in patients with advanced cancer. The primary goal of this trial was to determine whether a shark cartilage product improved overall survival for patients with advanced cancer who were getting standard care. Secondary research goals were to evaluate toxicities, tolerability, and quality of life associated with this shark cartilage product. METHODS: The study was a two-arm, randomized, placebo-controlled, double-blind, clinical trial. Patients with incurable breast or colorectal carcinoma had to have good performance status and organ function. Patients could be receiving chemotherapy. Patients were all to receive standard care and then to be randomly selected to receive either a shark cartilage product or an identical-appearing and smelling placebo 3 to 4 times each day. RESULTS: Data on a total of 83 evaluable patients were analyzed. There was no difference in overall survival between patients receiving standard care plus a shark cartilage product versus standard care plus placebo. Likewise, there was no suggestion of improvement in quality of life for patients receiving the shark cartilage, compared with those receiving placebo. CONCLUSION: This trial was unable to demonstrate any suggestion of efficacy for this shark cartilage product in patients with advanced cancer.