Cost-effectiveness of integrating buprenorphine-naloxone treatment for opioid use disorder into clinical care for persons with HIV/hepatitis C co-infection who inject opioids

Abstract

Background: Untreated opioid use disorder (OUD) affects the care of HIV/HCV co-infected people who inject opioids. Despite active injection opioid use, there is evidence of increasing engagement in HIV care and adherence to HIV medications among HIV/HCV co-infected persons. However, less than one-half of this population is offered HCV treatment onsite. Treatment for OUD is also rare and largely occurs offsite. Integrating buprenorphine-naloxone (BUP-NX) into onsite care for HIV/HCV co-infected persons may improve outcomes, but the clinical impact and costs are unknown. We evaluated the clinical impact, costs, and cost-effectiveness of integrating (BUP-NX) into onsite HIV/HCV treatment compared with the status quo of offsite referral for medications for OUD.

Methods: We used a Monte Carlo microsimulation of HCV to compare two strategies for people who inject opioids: 1) standard HIV care with onsite HCV treatment and referral to offsite OUD care (status quo) and 2) standard HIV care with onsite HCV and BUP-NX treatment (integrated care). Both strategies assume that all individuals are already in HIV care. Data from national databases, clinical trials, and cohorts informed model inputs. Outcomes included mortality, HCV reinfection, quality-adjusted life years (QALYs), costs (2017 US dollars), and incremental cost-effectiveness ratios.

Results: Integrated care reduced HCV reinfections by 7%, cases of cirrhosis by 1%, and liver-related deaths by 3%. Compared to the status quo, this strategy also resulted in an estimated 11/1,000 fewer non-liver attributable deaths at one year and 28/1,000 fewer of these deaths at five years, at a cost-effectiveness ratio of $57,100/QALY. Integrated care remained cost-effective in sensitivity analyses that varied the proportion of the population actively injecting opioids, availability of BUP-NX, and quality of life weights.

Conclusions: Integrating BUP-NX for OUD into treatment for HIV/HCV co-infected adults who inject opioids increases life expectancy and is cost-effective at a $100,000/QALY threshold.

Keywords: HIV; Hepatitis C; Integrated care; Opioid use disorder.

Figure 1. Tornado diagram of one-way sensitivity analyses

A range of parameters varied in one-way sensitivity analyses are displayed on the vertical axis. The ICER (US dollars/QALY) of integrated care compared to the status quo is represented on the x-axis. The solid vertical line indicates the ICER of the base case (US$51,700/QALY). The dashed vertical line represents the willingness-to-pay threshold of US$100,000/QALY. For each parameter, the horizontal bar represents the range of ICERs that result from varying that parameter along the range of values indicated in the parentheses; the first value listed in the parentheses is the one that results in the lowest ICER. SMR=standardized mortality ratio; HCV=hepatitis C virus.

Figure 2. Two-way sensitivity analysis of cost and efficacy of buprenorphine-naloxone (BUP-NX) in the integrated care strategy compared to the status quo.

Projected ICERs with the integrated care strategy compared to the status quo in two-way sensitivity analysis varying the efficacy and cost of buprenorphine-naloxone. The base case is indicated by the X in the figure. The figure demonstrates that the integrated care strategy is cost-effective compared to the status quo with an ICER ≤$50,000/QALY when the cost is halved and the efficacy greater than or equal to the base case. Compared to the status quo, the integrated care strategy is no longer cost effective at a willingness-to-pay threshold of $100,000/QALY when the efficacy is 25% of the base case and the cost is greater than or equal to the base case. Efficacy is defined as the likelihood that an individual transitions from active to former injection use and does not transition back to active use.