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The focus of new research efforts to improve the morbidity and mortality associated with acute myocardial infarction (AMI) has turned to adjuvant agents that show promise of improving outcomes following coronary thrombolysis. We enrolled 162 patients with AMI in a randomized trial comparing front-loaded tissue-plasminogen activator (t-PA) plus weight-adjusted heparin with anisoylated plasminogen streptokinase activator complex (APSAC) without heparin as well as standard-dose (325 mg) and low-dose (81 mg) aspirin. The primary end point was an in-hospital morbidity profile; secondary end points were clinical and angiographic potency and hemorrhagic events. Selected sites performed an electrocardiographic substudy to determine the time to 50% ST-segment recovery and the time to steady state. Although the trial was terminated when the Global Utilization of Streptokinase and t-PA for Occluded Coronary Arteries-I trial showed that t-PA had a significant mortality advantage over streptokinase, important trends were evident. Patients given t-PA and heparin were better anticoagulated (p = 0.001), yet AP-SAC-treated patients had more bleeding complications. The primary end point favored t-PA (25.4% vs 31.3%), and the secondary end points were similar in both groups. In the electrocardiographic substudy, the t-PA group achieved both 50% ST-segment recovery and steady-state recovery sooner than the APSAC group. Patients taking low-dose aspirin had lower in-hospital mortality and less recurrent ischemia but more strokes than the standard-dose aspirin group. Thus, this trial demonstrated trends favoring front-loaded t-PA with weight-adjusted heparin over APSAC without heparin in the treatment of AMI. The use of low-dose aspirin did not appear to impose a loss of protection from adverse events, nor did standard-dose aspirin increase serious bleeding.

During a 3-year period 39 evaluable patients with stage III and IV non-Hodgkin's lymphomas and unfavorable histologies were treated with a unique chemotherapeutic regimen based on a modified CHOP combination to which was added the nitrosourea, CCNU. Complete response was observed in six of 15 (40%) patients with diffuse poorly differentiated lymphocytic lymphoma (DPDL), four of 11 (36%) with diffuse mixed histiocytic lymphocytic (DML), and seven of 13 (54%) with diffuse histiocytic lymphoma (DHL). Of the 17 patients who achieved complete response, nine (53%) have remained continuously disease-free for greater than 2.5 years (2.7-4.1 years) from the onset of therapy: four of six with DPDL, two of four with DML, and three of seven with DHL. Median survival was 18.9 months for all patients, 18.9 months for those with DPDL, 17.4 months for those with DML, and 9.7 months for those with DHL. The median survival has not been reached for patients who attained a complete response, and will exceed 3.3 years. Central nervous system relapse was observed in three patients. In general, toxicity was moderate and consisted primarily of leukopenia, nausea, vomiting, and neurotoxicity. There were no drug-related deaths. The addition of CCNU to a modified CHOP combination resulted in an effective, generally well-tolerated out-patient regimen. However, it did not appear to decrease the rate of CNS relapse or improve current treatment results observed with other adriamycin-containing regimens for similar patients.

A phase II trial of prolonged IV infusions of vincristine was conducted in 21 patients with refractory acute leukemia. Patients received 0.25-0.50 mg/m2 by infusion daily for 5 days after an initial 0.5-mg bolus. A partial response was observed in one of two patients with acute lymphoblastic leukemia. Of 14 patients with acute nonlymphoblastic leukemia, a complete response lasting for 2.5 months occurred in one patient and a partial response lasting 1.3 months was observed in a second. No objective responses were noted in five patients with blast crisis of chronic granulocytic leukemia. Nonhematologic toxicity was minimal and, when present, generally consisted of a feeling of weakness; constipation, mucositis, and areflexia were also observed. Hematologic toxicity consisted mainly of mild to moderate reduction of platelets in most patients; marked thrombocytopenia (less than 50,000/mm3) occurred in two patients whose pretreatment platelet count was greater than 100,000/mm3. Although generally well tolerated, prolonged infusion of vincristine appears to have limited activity in the treatment of refractory acute nonlymphoblastic leukemia and blast crisis of chronic granulocytic leukemia; further evaluation is needed in acute lymphoblastic leukemia refractory to conventional bolus injection.

The potential interaction of the antitumor agents vincristine and VP-16-213 was investigated in vivo. DBA/2 mice were inoculated with 10(6) P388 murine leukemia cells, after which single IP injections of saline only, vincristine only, VP-16-213 only, or a combination of vincristine and VP-16-213 were administered. Long-term survival (greater than 60 days) was observed in 0/45, 1/45 (2%), 9/135 (7%), and 44/135 (33%) mice, respectively (P less than 0.001). Treatment was most effective when VP-16-213 was administered 0-72 h after vincristine. A similar trend was observed in mice bearing P1534 murine leukemia. These data demonstrate synergistic antitumor activity between vincristine and VP-16-213 in a murine model.