Cancer vaccines: is the future now?

Cancer immunotherapy is an area with a tremendous amount of promise. The field has matured in that the approaches and antigens appear very specific and highly reasonable. Furthermore, the pre-clinical models support their evaluation. In fact, the human immune responses against many of the vaccines are approaching thresholds that should start to impact disease. While the creativity and progress in technology was clearly evident, there is much work left to pursue. Clear evidence for this situation is reflected the low number of products and approaches that are in late-stage trials. This again reflects that many apparently promising technologies have trouble making the transition from mouse to human. However, the success in the antibody field strongly supports that once understood, the correct immunization strategies and antigens will have dramatic impact on disease. One improvement would be some optimization of approaches at least for immunogenicity in nonhuman primates. Another important issue for standardization, is to focus on the use of quantitative immune measurement systems rather than a reliance on bulk assay systems for decision-making. Such a minor change would allow more standardization of data interpretation across the field and allow for more rapid and intuitive vector evaluation, even if trials were not head to head. In this regard, the development of class II tetramer technology to the evaluation of tumor antigens where available would be a welcome advance. Furthermore, in general, flow-based assays for immune evaluation are similarly gaining acceptance. It is important to remember that the success of recent antibody products for lymphoma and breast cancer did not happen overnight. Rather, those successes were 20 years in the making. In this regard, for cancer immunotherapy, which is T-cell based, this similar anniversary is not yet upon us but it is getting close. The next few years are critical to this emerging field and likely to be full of promise, surprises and even success.