The cost-effectiveness of diacetylmorphine compared to methadone in chronic treatment
refractory opioid dependent individuals
Nosyk B (1), Guh DP (1), Miekleham E (1), Bansback NJ (1), Oviedo-Joekes E (1,2), Brissette S
(3), Marsh DC (4), Schechter MT (1,2), Anis AH (1,2)
1. Centre for Health Evaluation & Outcome Sciences, Vancouver BC, V6Z 1Y6; 2. School of
Population & Public Health, University of British Columbia; 3. Universite de Montreal; 4.
Northern Ontario School of Medicine.
Abstract
Background
Treatment for opioid dependence has been limited to substitution therapy with either methadone
or buprenorphine in most settings. In observational and experimental settings in Europe,
Diacetylmorphine (DAM) has been proven effective among non-responsive patients. The North
American Opiate Medication Initiative (NAOMI) evaluated the effectiveness of DAM versus
optimized Methadone Maintenance Treatment (MMT) in a cohort of chronic, treatmentrefractory opioid addicts. The study showed higher rates of retention and response to DAM vs.
MMT after one year of treatment.
Methods
A Semi-Markov cohort model was constructed to capture the chronic, recurrent nature of opioid
dependence. Trial-based data was supplemented with administrative drug dispensation data for
British Columbia, Canada, and other published data sources. Incremental cost-effectiveness
ratios, stating the cost per quality-adjusted life year gained, were calculated to compare DAM to
MMT for chronic, treatment-refractory opioid dependent patients.
Results
A representative individual in the MMT cohort lived an additional 14.03 (53% spent in
treatment) years following entry into their third treatment episode. The individual accumulated
8.332 discounted QALYs and a societal cost of $1,250,037 in present-value. A comparable
individual with unrestricted access to DAM lived an additional 15.25 years (66% spent in
treatment), accumulating 9.180 discounted QALYs and a societal cost of $1,195,164 in present
value. Baseline model estimates thus suggested that providing DAM to chronic, treatment
refractory opioid dependent individuals provides greater incremental health benefits (0.848
incremental QALYs gained with access to DAM) and reduced the total costs to society borne by
the hypothetical study cohort ($54,873 in cost savings with access to DAM). One-way and
probabilistic sensitivity analysis confirmed these results for shorter time horizons (1, 5 and 10
years) and a wide range of valuations of societal willingness to pay to achieve a gain of one
QALY.
Conclusions
A treatment strategy including DAM was cost-saving among a representative cohort of
individuals with chronic, treatment refractory opioid dependence.