EMBARK post hoc analysis of sexual activity (SA) patient-reported outcome (PRO) measures.

Abstract

313 Background: In the phase 3 EMBARK trial (NCT02319837), enzalutamide (ENZ) + leuprolide (L) and ENZ monotherapy (mono) delayed metastasis-free survival (MFS) vs placebo (P) + L without impairing global health-related quality of life (HRQoL) in high-risk biochemically recurrent (BCR) nonmetastatic hormone-sensitive prostate cancer (nmHSPC) (PSA doubling time ≤9 months). A prespecified PRO analysis showed that SA (measured as a composite score using European Organization for Research and Treatment of Cancer QoL Questionnaire-Prostate 25 [QLQ-PR25]) was better preserved with ENZ mono vs P + L and no significant difference between ENZ + L vs P + L. A post hoc analysis at the HRQoL item level was conducted to understand the effect on SA in each comparison and enable shared decision-making between physicians and patients. Methods: Men with high-risk BCR nmHSPC were randomized (1:1:1) to ENZ + L (double blind), ENZ mono (open label), and P + L (double blind). HRQoL was assessed at baseline and every 12 weeks until metastasis/death. This post hoc analysis assessed effects on time to confirmed (two consecutive visits) deterioration (TTCD) using predefined thresholds of one category decline from baseline in sexual interest, activity, satisfaction, erectile function, and feeling like a man using QLQ-PR25 item 50; QLQ-PR25 item 51; FACT-P item GS7; FACT-P item BL5; and FACT-P item P5 measures, respectively (Table). Intent-to-treat principle was applied. Results: At baseline, 327–332 men per arm completed the PRO surveys; overall completion rates were ≥85%, except for GS7 (≤36% due to voluntary response). ENZ mono vs P + L : TTCD in items 50 (interest) and 51 (activity), GS7 (satisfaction), and BL5 (erectile function) was delayed with ENZ mono. ENZ + L vs P + L: no significant differences in TTCD were observed, except a shorter TTCD by a median 0.06 months in BL5 (erectile function) with ENZ + L (Table). Conclusions: This post hoc item-level analysis of the EMBARK trial confirmed that SA was better preserved with ENZ mono vs P + L in terms of interest, activity, satisfaction, and maintaining erection. Further, the SA PROs were similar between ENZ + L and P + L, implying there is no further SA burden when adding ENZ to androgen-deprivation therapy. Clinical trial information: NCT02319837 . [Table: see text]