Phase I Study of the Intravenous Administration of Attenuated Salmonella typhimurium to Patients With Metastatic Melanoma

PURPOSE: A strain of Salmonella typhimurium (VNP20009), attenuated by chromosomal deletion of the purI and msbB genes, was found to target to tumor and inhibit tumor growth in mice. These findings led to the present phase I study of the intravenous infusion of VNP20009 to patients with metastatic cancer. PATIENTS AND METHODS: In cohorts consisting of three to six patients, 24 patients with metastatic melanoma and one patient with metastatic renal cell carcinoma received 30-minute intravenous bolus infusions containing 106 to 109 cfu/m2 of VNP20009. Patients were evaluated for dose-related toxicities, selective replication within tumors, and antitumor effects. RESULTS: The maximum-tolerated dose was 3 × 108 cfu/m2. Dose-limiting toxicity was observed in patients receiving 1 × 109 cfu/m2, which included thrombocytopenia, anemia, persistent bacteremia, hyperbilirubinemia, diarrhea, vomiting, nausea, elevated alkaline phosphatase, and hypophosphatemia. VNP20009 induced a dose-related increase in the circulati...