Objective: To investigate the efficacy and toxicity of dimethyl phenylatriazene(DM PTA) in the treatment of various
solid tumors. Methods: The initiating dose for phase Ⅰ
clinical trial was 80 mg/m2 and escalated based on Fibonaci rule. The recommanded dose of phase Ⅱ clinical study was 1 600 mg/m2 for consecutive days. Results: Thirty six patients were enrolled in phase Ⅰ clinical trial. The MTD was 2 000 mg/m2. The dose limiting toxicity was nausea/vomiting. The recommanded dose for 5 phase Ⅱ study was 1 600mg/m2 in 5 consective days every 3 weeks. Fifty nine patients with advanced cancer were enrolled into phase Ⅱ clinical trial including 25 patients with NSCLC, 5 SCLC, 7 NHL,5 HD ,7 melanoma, 6 breast carcinoma and 4 others. 2 PR (1 patient with advanced melanoma and 1 breast carcinoma with pulmonary metastasis ) and 2 MR were observed after at least 2 course of DA PTA treatment with overall
response rate of 3.6%(ITT). Meanwhile improvement was observed in 2 with malignant pleural effusion following the intrapleural adminstration. Major toxicity was nausea and vomiting with no apparent organ toxicities. With the support of 5 HT3 antagonist, 6 patients were treated at higher dose (2 600-3 000mg/m2,d1-5), however, no objective response was obtained, and all of them suffered from transient locoregional muscle spasm. Conclusion: Dimethyl phenyltriazene (DM PTA), a DTIC analogue, though seemed promising in pre clinical studies, only minimal clinical response was obtained in this clinical study.