Autologous large multivalent immunogen vaccine in patients with metastatic melanoma and renal cell carcinoma

Objective: To evaluate the safety and activity of large multivalent immunogen (LMI), prepared by immobilizing autologous tumor cell plasma membrane on 5-mu m diameter silica beads, in patients with melanoma and renal cell carcinoma (RCC). Methods: Thirty patients with stage IV metastatic melanoma and 31 patients with stage IV RCC were randomly assigned to I of 3 trial arms and received monthly treatment with (1) LMI alone, (2) cyclophosphamide followed 8 days later with LMI, or (3) the same treatment as in arm 2 with IL-2 given for 5 days beginning 1 week after LMI administration. Results: No grade 4 toxicities were observed. For patients with melanoma, median overall survival time for all 30 patients was 20.4 months [95% confidence interval (CI): 8.0-not assessable], and median progression-free survival was 2.8 months (95% CI: 1.9-6.3). For patients with RCC, median overall survival exceeded 46.2 months (95% CI: 30.3-not assessable), and median progression-free survival was 12.2 months (95% CI: 4.6-not assessable). Two patients had a partial response to LMI treatment. Conclusions: Based on our results that demonstrate the safety and tolerability of LMI vaccine, further development of this therapy is warranted to evaluate its clinical efficacy.