Adding 6 cycles of docetaxel at the outset of hormonal therapy for prostate cancer has been shown to improve survival, especially in men with a high burden of disease. The much-anticipated report was presented in detail today at the ASCO Annual Meeting. Those of you who have followed this blog [prost8blog] will remember that I previously highlighted the CHAARTED trial when the trial was stopped prematurely because of the positive result.
The first author, Chris Sweeney, is a good friend and led the study in which several of our patients here in Denver were participants. Thanks guys!
This study randomized 790 men who presented with metastatic prostate cancer and who had never received hormone therapy (ADT) to receive ADT alone (393) vs. ADT plus chemotherapy with docetaxel (397) starting up front at the time the ADT was started. In patients with high-volume disease, defined as those men with visceral metastases or >3 skeletal mets including one beyond the pelvis and spine, there was an improvement of 17 months in overall survival from 33 months to 49 months with a p value of <.0006 for significance between the two arms of the trial. The men with lower volume of metastases are also doing better, but the curves for the two treatment arms have not met significance. There was reasonable balance in age, race, psa values, etc., between the arms. A key point is that 3/4 of the men initially treated with ADT alone went on to receive docetaxel at the time of progressive disease, meaning that this trial can reasonably be considered to reflect a "pay me now or pay me later" with docetaxel toxicity, and the men who were on the "pay me now" arm had the most benefit from the toxicity of the chemotherapy. There was good balance between the arms in terms of the number of men who received others of the newer treatments (abiraterone, enzalutamide, sipuleucel-T).
For prostate cancer, this is akin to the studies of using chemotherapy "up front" in the adjuvant setting that really got medical oncology going in the early 1970s in women with breast cancer. It opens the door to the study of using aggressive multimodality treatment, including the newer hormonal agents, and possibly vaccines, in men with high-risk disease at the very outset of their therapy, which should be the next studies. The problem with designing such studies is the very long period of time it takes to get answers. CHAARTED was opened in 2006 and only now, eight years later, do we have a result. The time could be dramatically shortened if more men would be placed on clinical trials. 1000s of men were treated with same-old, same-old treatment during the time we worked on CHAARTED. If 50% of them would have been put on this trial in the first two years, we could have had this result about four years earlier. Since that takes a major change in how medicine is practiced in the U.S., we still have the overwhelming challenge of why so many more women facing breast cancer go onto studies while so few men facing prostate cancer do.
This post originally was published on prost8blog and is reprinted with permission of Dr. Glodé.Click to Tweet: CHAARTED trial shows need for change in clinical trials and medicine - Dr. Glode blogs @ASCO: http://bit.ly/1osxqlr