ORLANDO, FL, USA (UroToday.com) - Gwenaelle Gravis, MD, from Institut Paoli-Calmettes in France presented long-term analysis of GETUG-AFU 15 which tested ADT vs ADT + docetaxel in 385 hormone naïve metastatic prostate cancer patients on intent-to-treat basis.
Patients received LHRH or maximum androgen blockade in addition to docetaxel 75 mg/m2 IV every 3 weeks (up to 9 cycles). Although there was a 14-month overall survival advantage in the combination therapy group, this did not reach statistical difference after 83 months median follow up (the initial report had 50 month median follow up). A subcohort analysis stratifying high- versus low-volume disease after ADT or ADT+ docetaxel also revealed no statistical difference in overall survival. However, Eric Small, MD, from UCSF gave a thorough post-mortem examination of the trial and pointed out several caveats to those interpreting the trial as negative. He compared the GETUG-AFU 15 trial to the CHAARTED trial presented by Dr. Christopher Sweeney at the ASCO 2014 meeting comparing the same two treatments in hormone naïve patients and which showed a significant overall survival advantage. In GETUG-AFU 15 there were less high-volume metastases patients. In CHAARTED, the effect was most pronounced in patients with high-0volume disease. There was also a much higher amount of post protocol docetaxel in the ADT-only group compared to CHAARTED which may have clouded the long-term results.
Lastly, in CHAARTED, post protocol abirarterone or enzalutamide was fairly equal in both groups but this is unknown in GETUG-AFU 15. Dr. Small concluded that upfront docetaxel is beneficial in hormone-naïve metastatic prostate cancer based on the results of CHAARTED and the design and post-protocol treatments which confound interpretation of GETUG- AFU15.
Presented by Gwenaelle Gravis, MD at the 2015 Genitourinary Cancers Symposium - "Integrating Biology Into Patient-Centric Care" - February 26 - 28, 2015 - Rosen Shingle Creek - Orlando, Florida USA
Institut Paoli-Calmettesm, Marseille, France
Reported by Phillip Abbosh, MD, PhD medical writer for UroToday.com