Immunotherapy with autologous tumor cell-BCG vaccine in patients with colon cancer: a prospective study of medical and economic benefits

We have completed a multicenter, randomized controlled phase III clinical trial in Stages II and III colon cancer patients with active specific immunotherapy (ASI) using autologous tumor cells with an immunomodulating adjuvant bacillus Callmette-Guerin (BCG) vaccine (OncoVAX (R)) in an adjuvant setting. In this study, patients were randomized to receive either OncoVAX (R) therapy or no therapy after surgical resection of the primary tumor and stratified by stage of disease. Since the biologic essence of the effective tumor immunotherapy is the presence in the vaccine of a minimum number of viable, metabolically active, autologous tumor cells, the processing of the vaccine product, occurred within 48 h after surgery. Analysis of prognostic benefit in the pivotal phase III trial, with a 5.8 year median follow-up, showed that a beneficial effect of OncoVAX (R) is statistically significant for all endpoints including recurrence-free interval, overall survival, and recurrence-free survival in Stage II colon cancer patients. Surgery alone cures approximately 65% of Stage II (Dukes B-2, B-3) colon cancer patients. In the remaining patients, OncoVAX (R) in an adjuvant setting, significantly prolongs recurrence-free interval (57.1% relative risk reduction) and significantly improves 5-year overall survival and recurrence-free survival. No statistically significant prognostic benefits were achieved in Stage III (Duke's C-1-C-3) patients. A health economics assessment was performed on these results in Stage II colon cancer patients using disease-free survival and overall survival (for the entire intent-to-treat population). Cost-effectiveness, cost-utility and sensitivity analysis were applied with, cost of life years, recurrence-free life years and quality adjusted life years (QALYs) as the primary endpoints to this analysis. The perspective of the economic analysis was the current direct medical cost established by the health care providers. The introduction of new technologies often leads to additional costs. This report verified that the use of OncoVAX (R) for patients with Stage II colon cancer not only has significant prognostic benefit and positive clinical outcomes, but also showed that OncoVAX (R) therapy yields impressive health economics benefits. (c) 2005 Elsevier Ltd. All rights reserved.