CHICAGO, IL USA (UroToday.com) - Presented by Fred Saad, MD, FRCS at the American Society of Clinical Oncology (ASCO) Annual Meeting - May 31 - June 4, 2013 - McCormick Place - Chicago, IL USA
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Impact of concomitant bone-targeted therapies (BTT) on outcomes in metastatic castration-resistant prostate cancer (mCRPC) patients (pts) without prior chemotherapy (ctx) treated with abiraterone acetate (AA) or prednisone (P)
Fred Saad, Karim Fizazi, Matthew R. Smith, Thomas W. Griffin, Anil Londhe, Dana E. Rathkopf, Arturo Molina, Charles J. Ryan
University of Montreal, Montreal, QC, Canada; Institut Gustave Roussy, University of Paris Sud, Villejuif, France; Massachusetts General Hospital Cancer Center, Boston, MA; Janssen Research & Development, LLC, Los Angeles, CA; Janssen Research & Development, LLC, Raritan, NJ; Memorial Sloan-Kettering Cancer Center, New York, NY; Helen Diller Family Comprehensive Cancer Center, University of California-San Francisco, San Francisco, CA
Background: BTT can delay symptomatic progression in cancer pts with bone metastases. In a post hoc analysis, we assessed the impact of concomitant BTT on outcomes in a recent large, multinational study in mCRPC pts without prior ctx.
Methods: COU-AA-302 was a phase III trial in asymptomatic/mildly symptomatic pts with progressive mCRPC and no prior ctx. 1,088 pts were stratified by ECOG performance status (ECOG-PS, 0 vs 1) and randomized 1:1 to AA 1 g or placebo QD, plus prednisone 5 mg BID. Radiographic progression-free survival (rPFS) and overall survival (OS) were primary end points; secondary end points were times to opiate use, ctx, ECOG-PS deterioration, and PSA progression. The effect of concomitant use of BTT on all end points was assessed retrospectively using a stratified Cox regression model with factors for treatment, concomitant BTT, interaction of treatment and BTT, and baseline covariates. All data were obtained from a prespecified interim analysis at 55% OS events.
Results: Median follow-up at the time of analysis was 27.1 mos. Among intent-to-treat (ITT) pts, 184/546 AA and 169/542 P pts received concomitant BTT for treatment of bone metastases, either zoledronic acid (n = 330), other bisphosphonates (n = 16), denosumab (n = 22), and/or other BTT (n = 5). In these pts, concomitant BTT use was associated with improved OS, time to opiate use for cancer pain, and time to ECOG-PS deterioration.
Results were similar in a sensitivity analysis including only ITT pts with bone metastases at baseline. Conclusions: In this post hoc, exploratory analysis, concomitant BTT use was associated with delayed symptomatic progression in asymptomatic/mildly symptomatic mCRPC pts. This potential clinical benefit should be investigated in prospective studies. Clinical trial information: NCT00887198.
Fred Saad, MD, FRCS, is professor and chief of urology and director of G-U oncology at the University of Montreal Hospital Centers (CHUM). He holds the U of M Endowed Chair in Prostate Cancer and is director of the molecular oncology research lab in prostate cancer. He has recently been appointed director of clinical cancer research at the CHUM research center (CRCHUM). Since 2007 he serves as chair of the National Cancer Institute of Canada G-U Group and the Canadian Urologic Oncology Group.
He has published over 250 articles in several prestigious journals such as the New England Journal of Medicine, Lancet, JCO and JNCI. He sits on 7 editorial boards and is a reviewer for over 30 scientific journals. He is an author on over 800 scientific abstracts and 25 book chapters.
Dr Saad’s research interests include molecular prognostic markers, mechanisms of progression and new therapeutics in prostate cancer. He has over 40 clinical and basic research projects ongoing. To date he has received over 15 million dollars in research grants.