Clinical experience with 2'-deoxycoformycin.

2'-deoxycoformycin (DCF) is the oldest of the nucleoside analogs in clinical practice. The main use has been in the B and T lymphoproliferative disorders. The early significant activity with a high remission rate reported in hairy cell leukemia (HCL) has been confirmed within our group. Data from a large phase II study, which comprised 165 evaluable patients with HCL treated with DCF 4mg/m2 every 2 weeks until maximal response collected over a ten-year period, shows a very long disease-free interval with 76% of the complete responders still in remission at 6 years. Some activity has been reported in chronic lymphocytic leukemia and an outline of a phase II study with low dose DCF given over five days every month is summarised. DCF has been shown to be active in mature T-cell malignancies, chiefly T-prolymphocytic leukemia (T-PLL) and the cutaneous T-cell lymphoma, Sezary syndrome. Its efficacy in other forms of T-cell lymphoma has been less consistent but, bearing in mind the poor outlook of these disorders, the data suggest that DCF should be considered as part of the treatment strategy. In T-PLL, for example, partial remitters (and non-responders) to DCF have received the monoclonal antibody CAMPATH-1H with excellent results.