ESMO 2017: Initial Results from AQUARiUS, a Prospective, Observational, Multi-Centre Phase IV Study Assessing Patient-Reported Outcomes in mCRPC Patients Treated with Abiraterone Acetate plus prednisone or Enzalutamide

Madrid, Spain ( Antoine Thiery-Vuillemin presented initial results from a patient reported outcomes (PROs) study among men receiving either abiraterone + prednisone or enzalutamide. For mCRPC patients prior to chemotherapy, both abiraterone + prednisone [1] and enzalutamide [2] have demonstrated improved overall survival (OS) compared to placebo. Both medications are now commonly used to treat men with mCRPC, however data on PROs regarding these medications is limited. The objective of this study was to assess if there are differences in PROs and medical resource utilization for men with mCRPC treated with either abiraterone + prednisone or enzalutamide.

AQUARiUS is a phase IV, multi-center ongoing study evaluating PROs and medical resource use in two cohorts of chemotherapy naïve mCRPC patients newly initiated on abiraterone + prednisone or enzalutamide in the real-world setting. The study prospectively collects PROs on quality of life, cognition, fatigue and pain using EORTC QLQ-C30, FACT-Cog, BFI-SF and BPI-SF questionnaires, respectively, for 12 months in 211 patients. This analysis describes PRO data for 105 patients with 3-month follow-up (abiraterone + prednisone, n=46; enzalutamide, n=59). Multivariate repeated measures linear and logistic regression models were used to analyze change from baseline scores and risk for clinically meaningful worsening, respectively, adjusting for baseline characteristics.

Baseline characteristics were well balanced between the cohorts. Change from baseline comparisons favor abiraterone + prednisone over enzalutamide for months 1, 2 and 3 for perceived cognitive impairments (e.g., 1.1 vs -5.9 at month 3, p=0.02) and cognitive functioning (e.g., -0.6 vs -14.9 at month 3, p=0.04) and for month 2 and 3 for usual level and interference of fatigue (e.g., -0.7 vs 1.0 and -0.2 vs 0.7 at month 3, p=0.02). Within the first 3 months enzalutamide-treated patients had a significantly higher risk of experiencing clinically meaningful worsening in perceived cognitive impairments vs abiraterone + prednisone-treated patients.

In conclusion, initial results from the AQUARiUS study suggest favorable outcomes for perceived cognitive impairments, cognitive functioning, usual level of fatigue, and fatigue interference for abiraterone + prednisone vs enzalutamide within the first 3 months after treatment initiation. These results are based on initial data and await confirmation with further analyses, which will include more patients with longer follow-up.

Speaker: Antoine Thiery-Vuillemin, Universite de Franche-Comte, Besançon, France

Co-Authors: M. Poulsen (Odense, Denmark) A. Reid (Sutton, United Kingdom) E. Lagneau (Dijon, France) G. Ploussard (Toulouse, France) A. Birtle (Preston, United Kingdom) L. Dourthe (Strasbourg, France) D. Beal-Ardisson (Lyon, France) E. Pintus (Slough, United Kingdom) R. Trepiakas (Naestved, Denmark) M. Lukac (Beerse, Belgium) S. Van Sanden (Beerse, Belgium) L. Dearden (High Wycombe, United Kingdom)

Written By: Zachary Klaassen, MD, Urologic Oncology Fellow, University of Toronto, Princess Margaret Cancer Centre, Twitter: @zklaassen_md at the European Society for Medical Oncology Annual Congress - September 8 - 12, 2017 - Madrid, Spain


1. Ryan CJ, Smith MR, de Bono JS, et al. Abiraterone in metastatic prostate cancer without previous chemotherapy. N Engl J Med. 2013;368(2):138-148.
2. Beer TM, Armstrong AJ, Rathkopf DE, et al. Enzalutamide in metastatic prostate cancer before chemotherapy. N Engl J Med 2014;371(5):424-433.