A clinical phase I trial of gemcitabine and treosulfan in uveal melanoma and other solid tumours

This trial was performed to define the maximum tolerated dose (MTD) of treosulfan administered in combination with a fixed dose of gemcitabine in uveal melanoma patients. Preclinical studies suggested synergistic activity against uveal melanoma. Gemcitabine (1 g/m2) and treosulfan (2.5-4 g/m2) were administered on days 1 and 8, and cycles were repeated on day 29 for a maximum of six cycles. For treosulfan, dose escalation cohorts of 2-4 patients were enrolled. An additional 25 patients were entered at treosulfan dose levels II (3 g/m2) and III (3.5 g/m2). Thirty three patients with uveal melanoma and six patients with other histologies were accrued. Side-effects were predominantly haematological. The MTD was 3.5 g/m2 of treosulfan together with 1 g/m2 of gemcitabine. In the uveal melanoma patients, one partial response (PR) and 15 stablisations of disease (SD) were recorded and whether this translates into a survival gain should be explored further.