Abstract: Objectives: Combined high-dose Interferon-α and psoralen plus ultraviolet A irradiation (PUVA) have been reported to be effective in the treatment of early mycosis fungoides (MF); however, our study is the first controlled prospective study in the literature exploring the activity and tolerability of the combination with low dosages and evaluating further clinical outcome of early-MF patients. Methods: We carried out a multicentric prospective Phase II clinical study on 89 patients with early-stage IA to IIA MF treated for 14 months with low-dose IFN-α2b (6–18 MU/wk) and PUVA. Treatment success was analysed in terms of freedom from treatment failure. Results and conclusions: Complete remission (CR) was achieved in 84% and an overall response rate in 98% of cases: six-month CR was associated with a non-confluent skin infiltrate at histology (P = 0.044) and 14-month CR with high epidermal CD1a+ dendritic-cell density (P = 0.030). The combination protocol was successfully tolerated and the most common reason of ‘failure’ was related to relapse and not to toxicity. Sustained remissions were achieved in 20% of patients. High CD8+ lymphoid T-cell density was associated with a lower relapse rate (P = 0.002). We think that our combination therapy can be considered an alternative approach compared with other modalities. Good immunological host surveillance in the skin lesions seems to be an optimal basis for the therapeutic success.