INTRODUCTION: Opioid use disorder (OUD) is associated with substantial physical, social, psychological, and economic burden. Despite this burden, to date few trials have included comprehensive patient-reported outcomes (PROs) in their assessment of treatment impact. This analysis aims to report the effect of monthly depot buprenorphine (SUBLOCADEâ„¢, RBP-6000) on patient-reported health status, health-related quality of life (HRQoL), treatment effectiveness, addiction severity, employment/insurance status, and treatment satisfaction.
METHODS: Patient-reported outcomes (PROs) were collected in an open-label, long-term safety and tolerability study of RBP-6000 in 669 treatment-seeking subjects with OUD (NCT# 02510014). The study included 257 subjects from a Phase 3, placebo-controlled, 24-week study (roll-over cohorts including n=32 from the placebo arm [roll-over placebo] and n=225 from the RBP-6000 arm [roll-over RBP-6000]) and 412 subjects who were newly enrolled (de-novo cohort). Subjects in the roll-over cohorts received up to 6 RBP-6000 injections over 25 weeks; subjects in the de-novo cohort received up to 12 injections of RBP-6000 over 49 weeks. PROs included EQ-5D-5L, SF-36v2, Treatment Effectiveness Assessment (TEA; including 4 domains [substance use, health, lifestyle, community] and a total score), Addiction Severity Index-Lite (ASI; including 7 problem areas [medical, employment status, alcohol use, drug use, legal status, social/family status, psychiatric status]), employment/insurance status items, and Medication Satisfaction Questionnaire (MSQ). Changes from baseline measured at end of study (EOS, Week 25 for roll-over and Week 49 for de-novo) were analyzed using mixed models for repeated measures. Baseline was defined as the last non-missing value prior to the injection on Day 1 in this open-label study.
RESULTS: Subjects in both roll-over cohorts had stable EQ-5D-5L and SF-36v2 scores, improvements from baseline (~1 point for domains, ~4 points for total score) in all the TEA domain and total scores, and improvements in 6 of the 7 ASI problem areas. The proportion of roll-over subjects employed and insured also remained stable. Eighty-one percent of roll-over placebo and 86% of roll-over RBP-6000 subjects reported treatment satisfaction. Within the de-novo cohort, EQ-5D-5L index (difference= -0.01, 95% CI -0.03, 0.02) and Visual Analog Scale (VAS) scores (difference= 1.64, 95% CI -1.01, 4.30), as well as SF-36v2 Physical Component Score (difference= 0.73, 95% CI -0.32, 1.79) remained stable; the SF-36v2 Mental Component Score (MCS) (difference= 5.00, 95% CI 3.46, 6.54) and TEA scores (~2-3 points for domains, ~9 points for total score) improved significantly from baseline. The ASI scores improved from baseline in 6 of the 7 ASI problem areas. The proportion employed increased by 7% (from 44.2% to 51.2%) between baseline and EOS, while the proportion of subjects insured remained stable (from 54.4% to 55.4%). Treatment satisfaction at EOS was reported by 89% of de-novo subjects.
CONCLUSIONS: Within this cohort, subjects treated with RBP-6000 for 12 months had sustained improvements in mental health, addiction severity, treatment effectiveness, proportion employed and had high treatment satisfaction. The change in SF-36v2 MCS reached the clinically meaningful level established in other populations with chronic conditions. Roll-over RBP-6000 subjects maintained their benefits on PROs during an additional 6 months of RBP-6000 treatment.
