Health-related Quality of Life for Abiraterone Plus Prednisone Versus Enzalutamide in Patients with Metastatic Castration-resistant Prostate Cancer: Results from a Phase II Randomized Trial.

Abiraterone and enzalutamide are associated with side effects that may impair health-related quality of life (HRQoL).

To assess patient-reported HRQoL, depression symptoms, and cognitive function for abiraterone versus enzalutamide.

We randomized 202 patients in a phase II study of abiraterone versus enzalutamide for first-line treatment of metastatic castration-resistant prostate cancer (ClinicalTrials.gov: NCT02125357).

Patients completed Functional Assessment of Cancer Therapy-Prostate (FACT-P) and Patient Health Questionnaire-9 (PHQ-9) questionnaires, and Montreal Cognitive Assessment (MoCA) cognitive assessments at baseline and on treatment.

To compare the change in FACT-P scores over time between treatment arms, we used a mixed model for repeated measures (MMRM). For FACT-P domains where there was an interaction between the treatment arm and age, we constructed separate models for patients aged <75 and ≥75yr. We compared the proportion of patients with clinically meaningful change from baseline for FACT-P, and the proportion of patients with an abnormal score and median change from baseline for PHQ-9 and MoCA using Fisher's exact test and Mann-Whitney U test.

In the MMRM analysis, there was a positive test for interaction in the treatment arm by age for total FACT-P (p=0.048). FACT-P change from baseline over time was better for abiraterone than for enzalutamide in the ≥75-yr model (p=0.003), with no difference in the <75-yr model (p>0.9). A higher proportion of patients experienced clinically meaningful worsening with enzalutamide for the physical and functional well-being domains (37% vs 21%, p=0.013; 39% vs 23%, p=0.015). The distribution of change in PHQ-9 scores from baseline favored abiraterone at weeks 4, 8, and 12. These analyses were not prespecified, and results should be considered to be hypothesis generating.

Patient-reported outcomes favored abiraterone compared with enzalutamide with differences in FACT-P HRQoL and PHQ-9 depression scores. Differences in the total FACT-P scores were seen only in the elderly patient subgroup.

In this report, we examined the change in patient-reported quality-of-life scores from the start of treatment over time for patients treated with abiraterone versus enzalutamide for metastatic castration-resistant prostate cancer. We found that elderly patients treated with abiraterone had better quality of life over time, with no difference between treatments for the younger subgroup of patients.

European urology. 2018 Dec 24 [Epub ahead of print]

Daniel J Khalaf, Katherine Sunderland, Bernhard J Eigl, Christian K Kollmannsberger, Nikita Ivanov, Daygen L Finch, Conrad Oja, Joanna Vergidis, Muhammad Zulfiqar, Martin E Gleave, Kim N Chi

Department of Medical Oncology, BC Cancer Vancouver Centre, Vancouver, BC, Canada., Department of Biostatistics, BC Cancer Vancouver Centre, Vancouver, BC, Canada., Department of Medical Oncology, BC Cancer Southern Interior, Kelowna, BC, Canada., Department of Medical Oncology, BC Cancer Fraser Valley, Surrey, BC, Canada., Department of Medical Oncology, BC Cancer Island Centre, Victoria, BC, Canada., Department of Medical Oncology, BC Cancer Abbotsford Centre, Abbotsford, BC, Canada., Department of Urological Sciences, The Vancouver Prostate Centre, University of British Columbia, Vancouver, BC, Canada., Department of Medical Oncology, BC Cancer Vancouver Centre, Vancouver, BC, Canada; Department of Urological Sciences, The Vancouver Prostate Centre, University of British Columbia, Vancouver, BC, Canada. Electronic address: .