Update on Opioid Use Disorder Treatment

A Changing Landscape

Beth Sproule, RPh, BScPhm, PharmD ^1,2
Maria Zhang, RPh, BScPhm, PharmD, MSc ^1,2
1 Centre for Addiction and Mental Health, Toronto, Ontario
² Leslie Dan Faculty of Pharmacy, University of Toronto

Opioid-related mortality continues to increase significantly in Ontario. In 2020 alone, there were 2,426 opioid-related deaths in our province, representing a 60% rise from 2019.¹ The illicit fentanyl supply is a key driver of the current opioid crisis as it directly contributed to 87% of the deaths in 2020.¹ The COVID-19 pandemic has only worsened this public health crisis, likely related to changes in the illegal drug supply due to supply disruptions, less access to services and harm reduction supports, and greater use of substances to cope with stress.²

SO HOW CAN PHARMACISTS HELP?

The roots of the crisis lie, in part, in the rise of prescription opioid availability over the last two decades and those risks are still present.^3-5 Continuing to advance and improve our opioid stewardship activities is critical in helping to prevent our patients from developing opioid use disorder and other iatrogenic opioid-related sequelae. Also, our take-home naloxone kit distribution efforts are vital in preventing overdose-related deaths. Between July 1, 2017 and June 30, 2018, Ontario pharmacies dispensed 91,456 take-home naloxone kits, accounting for 62% of all kits distributed in the province.⁶ Unfortunately, the impact may be dampened as many deaths occur without anyone else present to intervene.¹ Knowing this, pharmacists can ensure that their patients who use drugs know of local resources such as safe consumption/injection sites, and other harm reduction practices such as using drugs with a trusted family member or friend, in a space where they could be found quickly, and/or utilizing supports available, such as the National Overdose Response Service hotline (nors.ca) or technology such as Brave App or Lifeguard App.

For individuals living with opioid use disorder, there is an additional evidence-based effective method to saving lives where pharmacists play a central role – treating opioid use disorder. Pharmacotherapy is the most effective treatment for opioid use disorder, and we know that opioid agonist therapy (OAT) saves lives. The mortality risk is significantly reduced for people with opioid use disorder while in OAT treatment compared to out of OAT treatment – even in the era of illicit fentanyl.⁷

At the same time, the approach to providing OAT services is evolving as the opioid crisis advances, and we are experiencing fundamental change in Ontario. The most significant shift is the change in the role of the College of Physicians and Surgeons of Ontario (CPSO) in setting the standards of practice for methadone treatment. The CPSO Methadone Maintenance Treatment Program Standards and Clinical Guidelines from 2011 were rescinded in March 2021.⁸ This decision was taken because it was perceived that the exceptional status of methadone, and the high degree of oversight, disincentivized physicians in offering the service, thus limiting access for patients.⁸ This is similar to the rationale for Health Canada’s 2018 decision to remove the Section 56 exemption requirement for methadone prescribers – to improve access to treatment.⁹ Other recent practice changes include the adoption of non-traditional techniques for initiating buprenorphine (e.g., microdosing and/or home inductions)¹⁰, the availability of new long-acting buprenorphine formulations (i.e., extended release injection and subdermal implant)¹⁰, modified approaches for methadone treatment for people using fentanyl¹¹, increasing acceptance of slow-release oral morphine (SROM) for opioid use disorder¹², injectable OAT treatment options (i.e., hydromorphone, diacetylmorphine)¹³ and the growing availability of safer supply programs.^14,15 The goal of this article is to help pharmacists navigate these changes by highlighting the current guidance available and key messages.

OTHER EMERGING PRACTICES

Injectable forms of OAT (i.e., injectable hydromorphone and diacetylmorphine) have a well-developed evidence base over many years supporting their use for people who have not responded to oral OAT options.¹⁶ iOAT programs function similarly to other OAT programs, however, patients visit the clinic multiple times per day to inject prescribed pharmaceutical diacetylmorphine or hydromorphone. The clinics are staffed by trained healthcare professionals and peer support workers who can intervene quickly in cases of overdose. These programs have limited availability in Ontario, however, there is ongoing work to develop resources, raise awareness, provide support and identify and address barriers to this evidence-based treatment.¹⁷ A significant hindrance is the limited availability of funding support. Clinical and operational guidance are available for clinicians and health administrators through the Canadian Research Initiative in Substance Misuse.

Safer Supply Programs function as an additional response to the overdose crisis, with the goal to reduce the risk of overdose and overdose deaths by providing pharmaceutical opioids as an alternative to the toxic illicit supply. This harm reduction approach is intended to support those who continue to meet criteria for opioid use disorder despite being in OAT programs and/or individuals who face barriers in accessing OAT. Safer supply programs are generally offered through primary care settings (Community Health Centres or primary care clinics) allowing engagement in other health and social supports. A common model utilized is to provide a supply of SROM (daily observed dosing) in combination with take-home hydromorphone immediate-release tablets. Health Canada is supporting safer supply programs in Ontario allowing expansion of current programs and the development of new programs.^14,18,19 These include programs that provide scheduled dispensing through machines accessed using biometrics (MySafe Project).²⁰ Evaluation of these programs is underway to help guide the way forward. It will be helpful to have more information on the benefits of these programs (reduced harms related to opioid use, improved health and social outcomes), as well as how to mitigate potential unintended consequences (e.g., health complications from injecting tablets, tablet diversion to new users). A guidance document is available at Safer Opioid Supply Programs (SOS): A Harm Reduction Informed Guiding Document for Primary Care Teams. More information is available through the Safer Opioid Supply Ontario Community of Practice.

Other resources that may be useful for pharmacists, particularly those who are looking for a primer into opioid use disorder include the CRISM National Guideline for the Clinical Management of Opioid Use Disorder which provides high-level guidance on selecting between various opioid agonist treatments, without detailing exactly how to prescribe them.

Additionally, the Health Quality Ontario Opioid Use Disorder Quality Standard includes a strong statement confirming OAT as first-line treatment, and clear guidance for what people with opioid use disorder should expect from Ontario treatment providers. Lastly, for pharmacists working with older adults, the Canadian Guidelines on Opioid Use Disorder Among Older Adults make recommendations tailored to this population including prevention measures and treatment approaches.

SUMMARY

These guidance documents all speak to the importance to improving access to OAT for people with opioid use disorder, as well as ensuring quality of care to meet their needs. The focus on engaging and retaining people in treatment is a direct response to the current, still worsening opioid crisis. Understanding the patient, their situation and treatment goals is key to informing clinical decisions. This is facilitated by effective communication between pharmacists and prescribers. Good clinical documentation also assists pharmacists within practice settings. The CAMH guidance specifically for pharmacists (Opioid Agonist Maintenance Treatment: A Pharmacist’s Guide to Methadone and Buprenorphine for Opioid Use Disorder²¹) is being revised to continue to support practice. Many of the same tenets still apply, but clinical judgement and decisions tailored to the patient situation are essential. During this time of changing guidance, the significance of effective communication and collaboration cannot be overstated. Patient safety and their retention in treatment depend on it.