A Phase II Study of ACZONE™ (Dapsone) Gel, 5% As a Treatment For Tarceva® (Erlotinib)Related Rash

This will be a randomized, double-blind, parallel design study in subjects treated with Tarceva for non-small cell lung cancer (NSCLC) who subsequently develop a rash suspected to be related to Tarceva. Only subjects who are not glucose-6-phosphate dehydrogenase (G6PD) deficient, and who have locally advanced or metastatic NSCLC and have failed at least 1 prior chemotherapy regimen indicated for Tarceva treatment will be included. Subjects will be screened and consented for the study within 3 days of initiating Tarceva therapy and will be instructed to contact the Investigator immediately when signs or symptoms of rash appear on the face. Subjects will be enrolled into the study only if a rash develops on the face and it has been confirmed and evaluated against eligibility criteria for the study. Once enrolled, subjects will be randomly assigned to apply either ACZONE or placebo to the rash-affected areas of the face. Subjects will apply ACZONE / placebo treatment for 8 weeks, even if symptoms of the rash resolve completely. Specific efficacy assessments will include lesion counts, plaque area, erythema assessment, and pruritus assessment. Rash characteristics will be monitored using National Cancer Institute (NCI) Common Terminology Criteria Adverse Event (CTCAE) version 3.0 terms and severity descriptions and percentage of facial surface area (FSA) affected. Investigators will evaluate the subject's overall response to treatment according to a standardized multiple choice question. Throughout the study, photographs of the face will be taken. Safety will be followed for 10 weeks (8 weeks of therapy + 2 weeks of follow-up) by monitoring adverse events, concomitant medications, and chemistry and hematology parameters. Plasma dapsone and N-acetyl dapsone concentrations will be measured to determine systemic exposure to the study treatment. Steady state plasma concentrations of erlotinib will also be measured before and after initiating the study treatment to determine any potential effects of ACZONE on pharmacokinetics of Tarceva.