A Phase I Study of Topical Tempol for the Prevention of Alopecia Induced by Whole Brain Radiotherapy

The study, conducted from October 2000 to February 2003 with 12 patients, investigated the safety and effectiveness of Tempol, a nitroxide radioprotector, in preventing alopecia from whole brain radiotherapy. Tempol was applied to the scalp of 11 patients before each radiation session. Side effects were minimal, including hypoglycemia and skin reactions, but were not considered significant. Tempol was not found in the blood of over half the patients, and where detected, levels were low (0.4 to 3.1 µmol/L). Hair retention improved after modifying the application method, with full scalp hair retention in three of the last five evaluable patients. The study concluded that Tempol is safe, well-tolerated, and shows evidence of protecting against radiation-induced alopecia, leading to the initiation of a phase II study with a gel formulation to improve scalp exposure.