Imiquimod 5% cream for treatment of HIV-negative Kaposi's sarcoma skin lesions: A phase I to II, open-label trial in 17 patients

Background Kaposi's sarcoma (KS), a virus-associated neoplasm, can be treated locally or systemically with interferon alfa. Therefore, imiquimod, an immune response modifier able to induce interferon-α secretion in situ, could prove a good local treatment for KS skin lesions. Objective We sought to determine the efficacy and safety of imiquimod 5% cream for the topical treatment of classic or endemic KS skin lesions in patients who are HIV negative. Methods We conducted a prospective, open-label, single center, phase II clinical trial. Imiquimod cream was applied under occlusion 3 times a week for 24 weeks. The main efficacy end points were the safety of topical imiquimod and the overall clinical response in patients evaluated on the basis of modified AIDS Clinical Trials Group criteria at 36 weeks. The statistical analysis was based on the intent-to-treat data set. Results Seventeen patients were enrolled. Eight (47%) presented objective overall clinical response (2 complete and 6 partial responses). Tumor progression was noted in 6 patients. The most frequent side effects were local itching and erythema, seen in 9 patients (53%). Limitations This was not a randomized placebo-controlled study and was restricted to a small number of patients. Conclusion Topical imiquimod 5% cream had antitumor activity in about half the patients with classic and endemic KS and was generally well tolerated.