The continuing search for effective treatments for men with hormone refractory prostate cancer (HRPC) has been a long and not very successful story. To date, under scientific conditions, the only chemotherapy which has demonstrated any survival benefit for men with prostate cancer has been docetaxel with prednisone. However, the survival benefit is very limited, only 2.5 months.
It has not been for the lack of trials, but to date researchers have not been able to find any other drug that works, that extends the life of men with HRPC. Various investigation drugs have been tried, but none have demonstrated any additional survival benefit.
Some researchers have expanded their work to evaluate the potential of combining different drugs in combination, not dissimilar to the cocktails that have been successful in controlling AIDS/HIV.
Along this research direction, Ning et al. have reported very positive results from a Phase II trial in which they used the combination of bevacizumab with docetaxel and thalidomide.
They found that 90% of their subjects experienced a PSA decline that was greater than 50%. Additionally, 88% of the subjects had a PSA decline of more than 30% within the first three months of the trial.
They also found that the median overall survival of the men in the trial was 28.2 months, compared to the expected survival time using the current standard of care, docetaxel with prednisone, of only 14 months.
All the men experienced grade 3/4 neutropenia, but the researchers did indicate that all the men were able to manage the toxicity issues. However, I want to point out that neutropenia is not a mild side effect.
This small trial did demonstrate that the addition of bevacizumab and thalidomide to docetaxel is a highly active and might be able to double the survival time over the current standard, docetaxel with prednisone.
J Clin Oncol. 2010 Mar 22. Epub ahead of print.
Joel T Nowak, MA, MSW