Abstract 1275
Background
mCRPC with early progression (≤1year) or non-response to initial ADT carries a poor prognosis, and there is no consensus regarding second-line therapy for these patients (pts) [ADT poor responders]. Although AA+P is effective for chemo-naïve mCRPC, limited data is available for ADT poor responders; thus, we conducted this study to evaluate the efficacy and safety of AA+P as secondary treatment for this population.
Methods
This was a multicenter, open-label, single arm, 2-stage trial according to Simon’s minimax design [hypothesis: p0=0.150, p1=0.350, α = 0.025, β = 0.100], and 48 pts were required to efficacy analysis. Key eligibility: Chemo-naïve mCRPC (testosterone level
Results
Fifty pts were enrolled and 49 were evaluable for efficacy analysis. At baseline, the median age was 73 (range 55–86), the median PSA level was 28.34ng/mL (2.28-294.25), and the median duration of initial ADT was 6.4 months (1.4 –18.8). Among the patients, 90.0% had a total Gleason score ≥8, and all had a treatment history of bicalutamide. Most patients showed high treatment compliance (>95% with AA [n = 47/50, 94.0%] and P [n = 46/50, 92.0%]). PSA response rate was 55.1% (n = 27/49; 95%CI 41.3-68.1), and the PSA decline began after 4 or 8 weeks from baseline. The treatment was well tolerated with
Conclusions
This is the first study to investigate the efficacy of AA+P for ADT poor responders. The study demonstrated similar efficacy to the Phase 3 study COU-AA-302, which further supports the efficacy of AA+P for ADT poor responders. AA + P appears to be a promising treatment for initial ADT poor responders with an acceptable safety profile. This study is ongoing as follow up on time to PSA progression.
Clinical trial identification
NCT02405858 (March 27, 2015).
Legal entity responsible for the study
Janssen Pharmaceutical K.K.
Funding
Janssen Pharmaceutical K.K.
Disclosure
G. Arai: Clinical trials sponsored by AstraZeneca, Green Peptide, Janssen, MSD and Shionogi during the conduct of the study. M. Ogi, T. Takahara, K. Fukushima, K. Yoshizawa: Eemployee of Janssen Pharmaceutical K.K. K. Kobayashi: Clinical trials sponsored by Astellas, Bayer, Janssen and MSD during the conduct of the study. N. Okuno: Clinical trials sponsored by Astrazeneca, Janssen and Pfizer during the conduct of the study.