Abiraterone acetate plus prednisolone for hormone-naive prostate cancer (PCa): Long-term results from metastatic (M1) patients in the STAMPEDE randomised trial (NCT00268476)
Clarke, Noel W
Hoyle, Alex P
Parmar, M. K.
Sydes, M. R.
AffiliationInstitute of Cancer Research, Institute of Cancer Research, London, UK
MetadataShow full item record
AbstractBackground: Abiraterone acetate plus prednisolone previously showed a clear survival advantage in men starting long-term hormone therapy for prostate cancer in STAMPEDE, a randomized controlled trial using a multi-arm multi-stage platform design. STAMPEDE included a wide range of men with M1 or M0 disease. The LATITUDE trial, in patients with high-burden M1 disease only, reported a similar magnitude of effect to the comparable subset of STAMPEDE pts. We report long-term outcomes in the M1 subset of pts in STAMPEDE. Methods: All patients received androgen deprivation therapy (ADT). Stratified randomization allocated pts 1:1 to ADT alone or adding daily abiraterone acetate 1000mg + prednisolone 5mg (SOC+AAP) continued until PSA, radiological & clinical progression. The primary outcome measure was death from any cause. The data freeze for this long-term analysis was planned for 3yr after the primary survival results when a meaningful increase in data was anticipated. Analyses used Cox proportional hazards & flexible parametric models, adjusted for baseline stratification factors. Results: Of 1,917 pts contemporaneously randomized to these groups (Nov-2011 to Jan-2014), 1,003 (52%) had M1 disease. The M1 groups were balanced: median age 67yr; 48% high-burden, 44% low-burden, 8% burden not assessable; 94% newlydiagnosed; median PSA 97ng/ml. Median follow-up had increased from 3.5yr to 6.1yr & number of ADT-only deaths increased by 50%, from 218 previously to 329. With 244 ADT+AAP deaths, the adjusted HR¼0$60 (95%CI 0$50d0$71; p¼0.31x10-9) favouring ADT+AAP, with 5-yr survival improved from 41% ADT-only to 60% ADT+AAP. The relative effect of abiraterone was similar in low-burden (HR¼0$55; 95%CI 0$41d0$76) and high-burden (HR¼0$54; 95%CI 0$43d0$69) patients. Median time on ADT+AAP was 2.4yr, with a current maximum of 8.1yr. Toxicity at 4yr post-randomisation was similar, with 16% of patients in each group reporting grade 3 or higher toxicity. Conclusions: A sustained and substantial improvement in overall survival of M1 prostate cancer patients was achieved with ADT + abiraterone acetate + prednisolone, irrespective of burden of disease.
CitationJames N, Rush H, Clarke N, Attard G, Cook A, Dearnaley D, et al. 611O Abiraterone acetate plus prednisolone for hormone-naïve prostate cancer (PCa): Long-term results from metastatic (M1) patients in the STAMPEDE randomised trial (NCT00268476). Annals of Oncology. 2020;31:S509-S.
JournalAnnals of Oncology
TypeMeetings and Proceedings