Methadone for Opioid Use Disorder—Decades of Effectiveness but Still Miles Away in the US

In 1974, President Nixon signed the Narcotic Addiction Treatment Act, which gave statutory authority to the regulations governing the provision of methadone for the treatment of opioid use disorder (OUD) in the US. The original name for the bill was revealing: the Methadone Diversion Control Act. These regulations that were meant to restrict dispensation on methadone have undergone only modest revision over the ensuing decades even in the midst of a current overdose epidemic.¹ In the US, methadone for OUD can only be provisioned at federally certified opioid treatment programs (OTPs). Patients receiving methadone must present to an OTP for initial evaluation and then return 6 days a week for medication dispensing for at least the first 90 days of treatment (the latter requirement was relaxed during the coronavirus disease 2019 [COVID-19] pandemic). At least weekly dispensing is required through the first year and only if patients meet specific requirements. The federal law (42 CRF 8) also mandates patients regularly engage with counseling services; state and municipal governments then layer on additional requirements.

To meet these requirements, patients receiving methadone face a high frequency of travel to and from OTPs (at least 24 trips during the first 4 weeks) and often at long distances given the shortage of methadone facilities. This shortage and high travel frequency mean travel and associated costs uniquely affect access to methadone compared with other chronic disease treatments.^2,3 Like other health care services, OTPs are clustered within urban communities, but the current overdose epidemic has affected urban and rural communities within the US.⁴

Other high-income nations have adopted different approaches to methadone provision. Australia, Canada, and the UK allow primary care methadone prescribing for OUD. While methadone prescribing still occurs within specialized substance use treatment facilities, these nations also allow methadone dispensing within local pharmacies, expanding the number of facilities available for observed dispensing.² Within the US, the regulatory burden on methadone provision effectively prohibits the integration of methadone prescribing into primary care, even in rural communities where there may exist no specialty substance use treatment options. Current federal regulations allow other facilities, such as federally qualified health centers or pharmacies, to serve as satellite medication units for observed dispensing and allow for exemption from federal requirements if a treatment shortage can be demonstrated. However, state regulations often prohibit these options and uptake has remained limited.⁵

This methadone landscape within the US has led to calls for federal action to enable the integration of methadone into primary care and to widen options for observed medication dispensing.^2,6 Recent data support these changes in regulation as a way of improving methadone access. Our 2019 study published in JAMA found, using geographical information system technology, that the urban-rural disparity in drive time to methadone could be mitigated if methadone provision occurred within federally qualified health centers.³

Now a study by Kleinman⁷ in this issue of JAMA Psychiatry expands on this previous work, providing data that support methadone provision in pharmacies. Using a similar cross-sectional geographical information system approach, the study examined how pharmacy-based dispensing would affect drive times to the nearest methadone facility for the general population. This study improves on our previous work in 2 important ways: (1) it used the smaller census tracts for drive time estimation, and (2) it examined drive time to methadone services among a national sample of census tracts. To estimate drive time, the study used comprehensive facility data from the Substance Abuse and Mental Health Services Administration treatment locator for OTPs and the National Provider Identifier database for pharmacies. For each census tract with a nonzero population, the study estimated drive time from the population-weighted center of a census tract to the nearest OTP and to the nearest pharmacy by simulating the legal movement of automobiles along a road network based on historical trip averages.⁷

The findings confirm nationally that drive time to nearest OTP increases with greater rural classification and identifies significant regional variation in drive time. Additionally, the study finds pharmacy-based methadone dispensing would reduce drive time to the nearest methadone facility, with greater reductions in rural census tracts. Nearly 18% of people live in census tracts 30 minutes or longer from the nearest OTP, while this is true for only 0.4% of people for pharmacies.⁷ Importantly, the study also estimates patient driving costs using average gasoline costs and suggests populations living in the most rural counties would need to spend nearly $300 on round-trip gasoline during the first 4 weeks of treatment.⁷

These results strikingly illustrate the limited extent of geographic methadone access, but important questions remain. As noted by Kleinman,⁷ there are 3 reasons the results may overestimate true geographic access to OTPs: (1) not all OTPs offer methadone maintenance, (2) not all OTPs may accept new patients, and (3) traffic, weather, construction, and public transportation may create travel impedance. The COVID-19 pandemic may exacerbate each of these factors by disrupting OTP operations and the availability of public transportation. Methadone requires greater travel than other chronic disease treatments,³ but we do not know how travel time affects individual OUD outcomes and whether this varies by geography. A Euclidean distance beyond 10 miles has been associated with reduced methadone treatment retention,⁸ but further research is needed. Additionally, the geographic distribution of patients with OUD likely differs from the geographic distribution of the general population. While it is recommended that all medications for OUD be available in all treatment settings,⁹ geographic analysis informed by OUD prevalence would allow for geographic prioritization of expansion.

Federally qualified health centers and pharmacy-based methadone provision provide a means to expand observed dispensing without construction of new facilities, and many chain pharmacies provide health care services such as vaccines and laboratory tests within private areas.^2,10 Behavioral interventions, such as contingency management, could be adapted to pharmacy settings,⁹ and federal and state policies should be amended to ensure any need to expand counseling does not delay methadone expansion.⁹ The results by Kleinman⁷ assume universal uptake of pharmacy dispensing. Resource constraints and stigma of methadone and the experiences of Australia and Canada suggest this is unlikely. In a 2020 study, our team found uptake of dispensing within 1 chain pharmacy reduced the urban-rural disparity in drive time to methadone.¹⁰ Together, these studies provide guidance as to the level of facility expansion needed to mitigate disparities.

Federal and state agencies are starting to take action to expand geographic access. The US Drug Enforcement Administration proposed to again allow mobile methadone units, and states such as Ohio and Kentucky have passed laws to enable greater use of federally qualified health centers and other facilities for dispensing.⁵ While these policies are welcomed, the results here by Kleinman⁷ and others suggest they fall short of needed expansion if patients’ rights to evidence-based care for OUD are to be ensured. Importantly, even with broad adoption of mobile or pharmacy-based dispensing, patients would still face a long drive time to a central OTP before starting methadone. The only way to address this barrier is to modify 42 CFR 8, and this should be urgently pursued in the context of the ongoing overdose epidemic. It is time for policies that truly support methadone treatment for OUD as opposed to focusing on diversion.