(ChemotherapyAdvisor) – A novel topical chemotherapy, mechlorethamine hydrochloride, 0.02%, gel, is safe and effective in the treatment of patients with mycosis fungoides (MF), the most common type of cutaneous T-cell lymphoma (CTCL), according to a pivotal phase 2 study in the January 2013 issue of JAMA Dermatology.
Response rates were 58.5% for the gel versus 47.7% for the comparator, compounded mechlorethamine, 0.02%, petrolatum ointment, using the Composite Assessment of Index Lesion Severity (CAILS) as the primary clinical end point, reported Stuart R. Lessin, MD, of Division of Dermatology, Fox Chase Cancer Center, Philadelphia, PA, and colleagues.
“After decades of reported use of topical mechlorethamine in MF-CTCL, to our knowledge, this clinical trial is the first to date to evaluate the efficacy and safety of topical mechlorethamine chemotherapy by comparing a novel mechlorethamine, 0.02%, gel with a compounded mechlorethamine, 0.02%, ointment in stage IA to IIA MF-CTCL,” Dr. Lessin stated. “The enrollment of 260 patients represents the single largest controlled clinical trial in MF-CTCL for any given treatment.”
The randomized, controlled, observer-blinded multicenter trial included patients who had not used topical mechlorethamine (nitrogen mustard) within 2 years and who had not used topical carmustine. Patients were randomly assigned to the mechlorethamine gel (n=130) or ointment (n=130) treatment arms. Mechlorethamine was applied once daily for up to 12 months. Tumor response and adverse events (AEs) were assessed monthly from months 1 to 6 and bimonthly from months 7 to 12.
Drug-related skin irritation resulted in 20.3% of patients in the gel treatment arm and 17.3% in the ointment treatment arm withdrawing from the study.
Serum drug levels were evaluated in a subset of patients and no systemic absorption of the study medication was detected.
During the 12 months of treatment and a 12-month follow-up period, six nonmelanoma skin cancers (one squamous cell carcinoma and five basal cell carcinomas) were detected in the treatment areas.