Optimal use of L‐asparaginase (NSC‐109229) in acute lymphocytic leukemia

Between 1971 and 1974, 646 evaluable patients under 20 years of age with previously untreated acute lymphocytic leukemia were treated according to Cancer and Leukemia Group B (formerly Acute Leukemia Group B) Protocol 7111. On a random basis, they received a 10‐day course of 1,000 units/kg/day of L‐asparaginase before, during, or after a 3‐week course of vincristine and corticosteroid. A control group received vincristine and corticosteroid for 4 weeks but no asparaginase. The overall complete remission rate was 85%, which was not altered significantly by any of the induction variables. Patients who received asparaginase for 10 days subsequent to vincristine and corticosteroid had a significantly longer complete remission duration with an estimated median of 45 months, compared to 20 months for the group receiving no asparaginase and 27 months for the other 2 asparaginase regimens. The beneficial effect of asparaginase was noted, irrespective of which 1 of the 2 intensification and maintenance programs the patients received. The 5‐year projection indicates a complete remission rate of 50% for those patients receiving subsequent asparaginase as compared to 41% of those induced on other regimens in this study and thus is superior to the use of only vincristine and corticosteroid. Copyright © 1977 Wiley‐Liss, Inc., A Wiley Company