OBJECTIVES : To study the cost-effectiveness of one-time and annual distribution of intranasal naloxone to high risk prescription opioid users using a US payer’s perspective.

METHODS : We constructed a Microsimulation model with health states for high-risk prescription opioid use, low-risk prescription opioid, discontinuation of prescription opioid, illicit opioid and discontinuation of illicit opioid. The model incorporated the risk of overdose, overdose being witnessed, naloxone being available and overdose death. We defined high risk users as persons with prescribed opioids in excess of 90 Morphine Milligram Equivalents in a month. We used a monthly cycle length and a life-time horizon. Quality-Adjusted Life Years (QALYs) and costs in 2017 USD were discounted 3% annually. One-time and annual distribution of naloxone were modeled with 100,000 individual trials for each scenario. We performed probabilistic sensitivity analysis (PSA) with 100 samples of 100,000 trials. The model was developed and analyzed in TreeAge Pro 2018.

RESULTS : In the one-time naloxone distribution scenario, 14 additional overdose deaths per 100,000 individuals were averted (1,648 deaths for usual care; 1,634 deaths for naloxone). A single distribution of naloxone had a total cost of $260.40 and 20.963 QALYs, with an incremental cost of $129.02 and incremental Quality Adjusted Life Days (QALD) of and 1.5 days translating to an Incremental Cost Effectiveness Ratio (ICER) of $35,507/QALY. In PSA, one-time naloxone distribution was cost-effective 69% of the time at a Willingness-To-Pay (WTP) threshold of 100,000/QALY. In the annual distribution scenario, naloxone averted 209 overdose deaths and had an incremental cost of $506.95, an incremental QALD of 6.2 days, and an ICER of $30,282/QALY.

CONCLUSIONS : Both one-time and annual naloxone distribution were found to be cost-effective at a WTP of 100,000/QALY. This indicates that increasing access to naloxone for high-risk prescription opioid users could be a cost-effective intervention.