Abstract
Elsewhere in this issue Rosenthal and Moloney present a three-drug combination therapeutic program which produced a 55 per cent complete remission rate in adults with acute granulocytic leukemia. They emphasize and discuss the rapid improvement that has occurred in the treatment of this disease during the past several years. The most important contribution to this improvement has been the anti-leukemic agent arabinosyl cytosine, which specifically inhibits DNA synthesis and is therefore cell-cycle specific. Consequently, the schedule of drug administration markedly influences the therapeutic index in experimental systems.1 In clinical studies there is similar evidence for schedule "sensitivity." The optimal schedule . . .