The evolution of prescribed safer supply in British Columbia : critical issues, opportunities, and lessons learned

Since the adulteration of Canada’s unregulated drug supply with illicitly manufactured fentanyl and other toxic contaminants began, people have called for novel interventions to prevent drug-related harms and deaths. Prescribed safer supply is one such intervention, entailing the provision of prescription medications as alternatives to toxic drugs. Amid the dual public health crises of COVID-19 and toxic drug poisoning, prescribed safer supply was rapidly implemented as an emergency risk mitigation measure. Throughout the implementation process, the intervention has evolved, generating evidence, significant debate, and controversy, ultimately leading to policy restrictions and program closures. Guided by the social ecological framework, this interdisciplinary dissertation draws on approaches from medicine, public health, and social science to trace the evolution of prescribed safer supply in British Columbia, a key site of safer supply innovation and contestation. Using qualitative and quantitative data, through three separate studies, I aimed to: (1) characterize the perspectives of physicians on tablet hydromorphone diversion, and how these perspectives shaped their prescribing practices; (2) examine the phenomenon of safer supply deprescribing among two cohorts of people who use drugs in Vancouver, BC; and (3) qualitatively evaluate the effectiveness of a fentanyl patch safer supply program in meeting its aims, including reducing the risk of overdose by decreasing reliance on the unregulated drug supply. Results from these studies show that, from physicians’ perspectives, tablet hydromorphone is an inadequate replacement for unregulated fentanyl for some patients, which may drive some diversion. Yet physicians’ perspectives about diversion are also shaped by peer networks, media, politicization, and the legacy of excessive opioid prescribing in the 2000s. Diversion concerns are a factor in deprescribing, particularly of tablet hydromorphone. Gender identification as a woman, experiencing nonfatal overdose, and difficulty accessing addiction treatment are positively associated with increased odds of deprescription. Fentanyl patch safer supply offers an alternative to tablet hydromorphone and supports patients in reducing their unregulated drug use; it may also address some physicians’ diversion concerns. This dissertation identifies limitations and opportunities for future innovation and scale-up, while underscoring the complicated ways in which social dynamics, sociohistorical patterns, and political conditions have shaped the intervention’s implementation.