From 1976 until 1978, 136 adult patients with acute leukemia were treated in four hospitals in Berlin. A complete remission was achieved in 47 patients (35%). Twenty-six patients with non-lymphocytic acute leukemia, who had achieved a complete remission with induction chemotherapy consisting of daunorubicin (45 mg/m2/day, day 1, 2 and 3) and cytosine-arabinoside (100 mg/m2/day, continuous infusion, day 1 to day 7) were entered into a randomized trial. Thirteen patients were treated with an intermittent combination chemotherapy at 4-week intervals; the other group of patients received in addition a specific immunotherapy consisting of neuraminidase-modified allogeneic blast cells. The results revealed that the addition of this kind of immunotherapy did not increase the duration of first remission or survival.