Prospects for cervical cancer vaccines.
As we have seen, the technical problems of developing cheap, effective vaccines against HPV associated tumours are formidable, but they are by no means insuperable. Experiments in cows with BPV2 show that both therapeutic and prophylactic vaccines work to some extent and the immunogens used are by no means the best that could now be envisaged. The fact that human trials are now under consideration or in progress with both protein vaccines and recombinant vaccinia virus vectors is also very encouraging. There are still both practical and ethical problems, as with any sexually transmitted disease, but the main problem is one of support. Pharmaceutical companies see no immediate profit in vaccines of this type, preferring to invest in drugs for treatment or diagnostic kits for detection. Vaccines against HPV are unlikely to be forthcoming, and indeed, the people most in need of protection against cervical cancer are the least able to afford any sort of treatment, especially a preventive one. This leaves the cancer charities, and these in their present financial difficulties are understandably reluctant to commit substantial resources to the long term programmes that are needed to tackle the problems of developing and evaluating candidate vaccines. It seems certain that intervention against HPV and cervical cancer will come in time, but with the present level of commitment, progress is inevitably going to be less rapid than one would like.