Enzalutamide for Advanced Prostate Cancer Does Not Worsen HRQoL

Enzalutamide delays metastasis in men with non-metastatic castration̶resistant prostate cancer (CRPC) without worsening health-related quality of life (HRQoL) and significantly decreases the risk of clinically meaningful HRQoL deterioration, according to data that will be presented at the 2018 American Society of Clinical Oncology (ASCO) Annual Meeting in Chicago, Illinois, on Saturday, June 2.¹

The findings are from the phase 3 PROSPER trial (ClinicalTrials.gov Identifier: NCT02003924), in which 933 and 468 asymptomatic men with non-metastatic CRPC were randomly assigned to receive enzalutamide and placebo, respectively. Gerardt Attard, MD, of the Institute of Cancer Research and Royal Marsden in the United Kingdom, and collaborators assessed patients’ HRQoL and pain at baseline and every 16 weeks during treatment using the Functional Assessment of Cancer Therapy-Prostate (FACT-P) and Brief Pain Inventory, Short Form.

They defined pain progression as 2 points or greater in pain severity items and increases in mean scores from baseline. They defined HRQoL improvement/deterioration as an increase/decrease from baseline using pre-established thresholds for clinically meaningful difference. The researchers using Kaplan-Meier estimates and Cox proportional hazards models to assess time to first confirmed (at 2 consecutive visits) and unconfirmed HRQoL deterioration/pain progression.

Baseline characteristics and scores were similar between study arms, with low pain (median 0) and high HRQoL (median FACT-P score: 121), the investigators noted. Most patients reported either no change or an improvement in HRQoL. The proportion of men with pain progression at week 49 was similar between enzalutamide (11% to 20%) and placebo (14% to 21%).

The investigators found a non-significant decreased risk of pain progression with enzalutamide compared with placebo (HR 0.78–0.93; P > 0.05) and a nominally significant lower risk of deterioration with enzalutamide for FACT-P total, FACT Advanced Prostate Symptom Index, prostate cancer subscale (PCS), and emotional well-being (EWB) in the confirmed (HR 0.75, 0.77, 0.77, 0.69, respectively; P < 0.05) and for PCS and EWB in the unconfirmed analyses (HR 0.82 and 0.80, respectively; P < 0.05).

Read more of Cancer Therapy Advisor‘s coverage of the American Society of Clinical Oncology (ASCO) 2018 meeting by visiting the conference page.

Reference

1. Attard G, Saad F, Tomal BF, et al. Health-related quality of life (HRQoL) deterioration and pain progression in men with non-metastatic castration-resistant prostate cancer (M0 CRPC): Results from the PROSPER study. J Clin Oncol. 2018: 36, (suppl; abstr 5010). Presented at 2018 ASCO Annual Meeting; June 1-5, 2018; Chicago, IL.