[The first results of assessment of clinical efficacy of melatonin and metformin in patients with disseminated skin melanoma receiving dacarbazine as first-line systemic therapy].

The aim of the study was to assess efficacy and safety of combined therapy with dacarbazine and melatonin or metformin in comparison with dacarbazine alone in the 1st line of therapy of cutaneous melanoma. Thirty-six patients with disseminated melanoma, therapy naïve, were included between March 2014 and December 2015. Patients received DTIC 1000 mg/m2 in day 1 of 28-day cycle either as monotherapy (group 1) or in combination with melatonin 3 mg PO daily (group 2) or metformin 850 mg 2 times a day PO daily (group 3). Thirty-four patients were randomized (15-in group 1, 8 - in group 2, 13 - in group 3) and received 119 cycles of therapy. Response rate was 11% in groups 1 and 2, and 8,3% - in group 3 (p=0,57). Median time to progression was 52, 79 and 63 days, respectively in the 1st, 2nd and 3rd group (р=0,468). Two patients from the 2nd and 3rd group showed delayed response to therapy. No adverse events of grade 3-4 were seen. Thus, DTIC with melatonin or metformin was well tolerated. No meaningful increase of adverse event incidence was seen. No benefit of either combination was shown in this interim analysis. Delayed responses in melatonin and metformin combination groups were registered. This suggests immunologic effect of both drugs and warrants further study.