Results from two of the comparisons of the STAMPEDE trial, adding the drug celecoxib (with or without zoledronic acid) to long-term hormone therapy for men with prostate cancer, were published yesterday in the Journal of Clinical Oncology.
Overall, the results show no benefit in survival of adding either celecoxib alone, or celecoxib plus zoledronic acid, to long-term hormone therapy, but there are results of significant interest in the sub-group analyses.
The results, looking at the entire group of men in the study, come as no surprise, since in 2012, a planned analysis of the trial showed that adding celecoxib, to hormone therapy did not add enough benefit to justify continuing to recruit more patients to these comparisons. The researchers continued to follow-up these men to monitor the long-term effects. These results (with an average of over five years of follow-up) were published today.
All the men in the trial received standard treatment, which was hormone therapy plus radiotherapy in some cases. Just over 300 men were randomised to receive celecoxib tablets for up to a year in addition. The researchers then compared the results for these men with those of more than 600 men who were allocated to the standard treatment without adding celecoxib. Adding celecoxib made no difference to how long men lived.
Another 300 men were randomised to have a combination of celecoxib and zoledronic acid, in addition to the standard treatment. These were compared to the same 600 men who had been allocated the standard treatment. Again, when looking at the entire group of men, this combination did not significantly improve how long they lived for. However, in the large subgroup of men whose disease had already spread to other parts of their body, mainly to bone, there was evidence to suggest this combination might help these men live longer. The size of this benefit was substantial.
This is the first trial to give any indication that a combination of celecoxib and zoledronic acid may improve survival for some men. There is not enough evidence to justify making this combination a standard treatment for prostate cancer, but it does raise some important questions. Further research is needed to investigate our findings, most likely in those men with prostate cancer for whom zoledronic acid is already being used.
The STAMPEDE trial received funding and support from Cancer Research UK, UK Medical Research Council, the UK National Cancer Research Institute, the UK Department of Health, Sanofi-Aventis, Novartis, Pfizer, Janssen, and Astellas.