Cost-Effectiveness of Medically Monitored Ibogaine for Opioid Use Disorder in Tennessee: A State-Specific Semi-Markov Analysis
Background: Opioid use disorder remains a major public health and healthcare-system challenge in Tennessee, where many adults remain untreated, undertreated, or poorly retained in care. Medically monitored ibogaine has been proposed as a potential intervention for OUD, but its economic implications in a state treatment environment have not been well characterized. We evaluated the health and economic consequences of adding a medically monitored ibogaine pathway to heterogeneous standard care for Tennessee adults with OUD.
Methods: We developed a Tennessee-specific cohort state-transition model with semi-Markov features comparing realistic limited-access medically monitored ibogaine with a matched no-ibogaine standard-care reference. The modeled comparator included methadone, buprenorphine, extended release naltrexone, non-MOUD treatment, and untreated or not-engaged care. The base-case cohort represented 106,000 Tennessee adults with OUD. The model used weekly cycles, a 10-year horizon, 3% annual discounting, and a healthcare-sector perspective. The primary cost endpoint was cumulative direct medical cost; primary health outcomes were quality-adjusted life-years, survival, and mortality. Scenario analyses, one-way deterministic sensitivity analysis, probabilistic sensitivity analysis with 5000 simulations, and program-cost threshold analysis were conducted.
Results: In the 10-year base case, medically monitored ibogaine was associated with lower direct medical cost, higher QALYs, and improved survival. Cumulative direct medical cost was $5.46 billion with ibogaine versus $6.42 billion with no ibogaine, yielding an incremental direct-cost difference of -$965.0 million. Total QALYs were 627,371 versus 530,144, corresponding to an incremental gain of 97,227 QALYs. Ten-year survival was 0.9308 versus 0.9098, an absolute survival gain of 2.10 percentage points. Because ibogaine was less costly and more effective in the base case, it was dominant. In scenario analyses, ibogaine remained less costly and more effective under waning efficacy and comparator-mix variation. In the conservative stress test, direct medical cost increased by $232.7 million, but ibogaine still produced 68,547 additional QALYs. In probabilistic sensitivity analysis, 72.9% of simulations were direct-medical-cost-saving, and 99.98%, 100%, and 100% were cost-effective at willingness-to-pay thresholds of $50,000, $100,000, and $150,000 per QALY, respectively. Program cost threshold analysis showed that ibogaine remained approximately cost-saving at $11,000 per treatment episode but became more costly at $15,000.
Conclusions: In this Tennessee-specific decision-analytic model, adding a medically monitored ibogaine pathway to heterogeneous standard care was associated with lower direct medical cost, higher QALYs, and improved survival over 10 years. Cost savings were sensitive to program cost and durability assumptions, but health gains persisted across conservative scenarios. These findings do not establish ibogaine as routine OUD care, but they suggest that a carefully monitored Tennessee ibogaine clinical-trial or implementation pathway could be economically plausible if it reduces relapse, hospitalization, and mortality while maintaining appropriate cardiac safety monitoring and escalation capacity.