According to the Sponsor's clinical development strategy and plan, the local metastatic melanoma with relapsed cutaneous/subcutaneous tumors, including melanoma-in-transit, has been chosen as the 1st indication for evaluating safety, tolerance and PK of DT01 in combination with a palliative radiotherapy (10x3 Gy). The presence of multiple cutaneous/subcutaneous tumor should provide an initial clinical evaluation of the safety and skin tolerance of the combined treatment of DT01 and 10x3 Gy irradiation, as well as a preliminary assessment of anti-tumor activity (proof of concept) of DT01 to sensitize and improve the response rate of radiotherapy (estimated about 50% response rate), and to delay local relapse.