Barcelona, Spain ( ENZAmet is an international, cooperative group, randomized phase 3 trial that recently showed, after a median follow-up of 34 months, treatment with enzalutamide, rather than an older non-steroidal antiandrogen, added to standard first-line treatment for metastatic hormone-sensitive prostate cancer (mHSPC), with or without concurrent early docetaxel, resulted in longer progression-free survival (HR 0.40, p < 0.001) and longer overall survival (HR 0.62, p = 0.002).1 This abstract reports on health-related quality of life (HRQL) outcomes from men treated on the ENZAmet study.

HRQL was measured with the EORTC QLQ-C30 and PR25 at weeks 0, 4, 12, and then 12-weekly until clinical progression. Mixed models for repeated measures were used to calculate the least squares mean difference, 95% CI, and p-value for comparisons of the randomly assigned groups for all assessments from week 4 to 156. For each analysis of deterioration-free survival, the endpoint was defined as the earliest of death, clinical progression, cessation of study treatment, or a 10-point worsening from baseline (minimum clinically important difference on scales scored from 0 to 100) in the pertinent HRQL sub-scale: physical functioning, global health and quality of life, cognitive functioning, and fatigue.

The authors found that during the study period, individual HRQL outcomes (eg physical function, cognitive function, fatigue) were significantly worse among patients receiving enzalutamide. Notably, global health and quality of life were maintained.

ESMO 2019 HRQL outcomes

A critical finding from this study, however, is that the addition of enzalutamide improved deterioration-free survival because early impairments in specific aspects of HRQL did not outweigh the subsequent benefits of delayed clinical progression, as shown below.

ESMO 2019 benefits of delayed clinical progression

This new HRQL data demonstrating improvements in deterioration-free survival with the addition of enzalutamide to androgen deprivation therapy (with or without docetaxel) in men with newly diagnosed mHSPC confirms this treatment regimen as a standard of care option in this clinical setting that maintains or improves patients’ global quality of life over time.

Presented by: Martin R. Stockler, MBBS, MSc, FRACP, Professor of Oncology and Clinical Epidemiology at The University of Sydney, Medical Oncologist at the Concord Repatriation General Hospital and Chris O’Brien Lifehouse RPA, and Oncology Co-Director at the NHMRC Clinical Trials Centre

Written by: Jacob Berchuck, MD, Medical Oncology Fellow at the Dana-Farber Cancer Institute (Twitter: @jberchuck) at the 2019 European Society for Medical Oncology Congress (#ESMO19), September 27th to October 1st, 2019, Barcelona, Spain

1. Davis ID, Martin AJ, Stockler MR, et al. Enzalutamide with Standard First-Line Therapy in Metastatic Prostate Cancer. N Engl J Med. 2019 Jul 11;381(2):121-131.

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Health-Related Quality Of Life After Apalutamide Treatment In Patients with Metastatic Castration-Sensitive Prostate Cancer (TITAN): A Randomised, Placebo-Controlled, Phase 3 Study