Phase II study of i.v. interferon-gamma in Japanese patients with mycosis fungoides

A multisite, open-label, non-randomized, single-arm phase II study was conducted to evaluate the efficacy and safety profiles of interferon-γ in Japanese patients diagnosed with stage IA-IIIA mycosis fungoides (MF). Interferon-γ was administrated i.v. to 15 patients at a dose of 2 million Japan reference units once daily over 5 days a week for the first 4 weeks, followed by subsequent intermittent injection. The primary efficacy end-point was the overall skin response during the study as assessed according to the evaluation criteria for chemotherapeutics for malignant skin carcinomas. Of the 15 patients, 11 (73.3%) achieved the objective response. Of the other four patients, three remained on treatment during study with stable disease and one showed disease progression. The median duration of stable disease was not reached but was 170 days or more (range, 29 to ≥253 days). As assessed according to the modified severity weighted assessment tool, nine patients (60.0%) achieved the objective response. The most common drug-related adverse event (AE) was influenza-like illness occurring in all patients enrolled, which did not lead to discontinuation of the study. Two serious AE were reported in two patients: aggravation of MF and aggravation of cataract, neither of which was considered directly related to the study drug. The patient with aggravation of MF died 50 days after the initiation of the study treatment. Another patient was withdrawn from the study due to drug-related cough, which disappeared after discontinuation of the drug. Overall, interferon-γ was effective and well-tolerated in Japanese patients with MF.