This phase II study is designed to determine the efficacy and safety of APO866 for the treatment of patients with advanced forms of cutaneous T-cell lymphoma (CTCL). APO866 has shown to induce growth inhibition in cultures of human CTCL cells as well as in animal models with subcutaneously implanted human CTCL tumors. APO866 was considered to be safe and well-tolerated in a phase I study that treated 24 patients with advanced cancer. APO866 is administered by intravenous infusion continuously for 96 hours and that is repeated every 4 weeks. Patients will receive 3 cycles of treatment and the primary efficacy endpoint will be assessed at Week 16. patients will be followed up for 12 months