Observational Prospective Study of Injectable Opioid Agonist Treatment (iOAT) and Tablet Injectable Opioid Agonist Treatment (TiOAT)

The iOAT & TiOAT Study


The ongoing opioid overdose public health emergency has highlighted fundamental gaps in substance use treatment services. There are a limited number of opioid agonist therapies (OAT) and established options like methadone or buprenorphine/naloxone (Suboxone®) do not work for everyone. There is strong research evidence and clinical experience to show that injectable opioid agonist treatment (iOAT) can be an effective option for people with opioid use disorder. With the release of a provincial guidance document in late 2017, clinical iOAT programs are expanding around the province. Additionally, tablet hydromorphone injectable opioid agonist therapy (TiOAT), where tablet hydromorphone is provided as a pharmaceutical alternative to the contaminated drug supply, and tablet hydromorphone prescribed as safer supply for people who inject opioids have emerged as promising yet understudied approaches.

iOAT study participants receive either liquid hydromorphone or diacetylmorphine and TiOAT study participants receive tablet hydromorphone either as part of a formal TiOAT program with wraparound services or as safer supply.

Details about iOAT programs and accessibility in BC and Canada are available on our National iOAT Environmental Scan page.


The iOAT & TiOAT Study is a provincial evaluation to assess short and long-term client-based outcomes over a five year follow up period through client interviews, urine drug testing and linkage to data held in a range of health and social databases. Participants enrolled in the TiOAT study additionally have data linkages to a clinical TiOAT Safety Data Collection Tool that is completed by a health care provider with the participant weekly during the first six weeks of treatment and elicits data on program attendance, average daily dose amounts, route of administration and participant-reported side effects is also gathered. A parallel qualitative study will provide additional information from interviews with both clients and services providers. 

This study aims to generate practice-based evidence for the provision of injectable opioid agonist treatment and tablet hydromorphone, in real time as the province scales up treatment within diverse clinical models of care. Key objectives include evaluation of:

  1. service utilization and treatment trajectories
  2. impacts on immediate harms associated with injection opioid use
  3. health and social outcomes

Study findings will inform health system policy and practice to ensure the most effective, timely and client centered scale up of clinical programs across the province and Canada - as part of the provincial response to the current overdose crisis, as well a new option within the continuum of care for opioid use disorder.


The iOAT & TiOAT Study is governed by a provincial Advisory Committee that includes the BC Centre on Substance Use, Ministry of Health, Ministry of Mental Health and Addictions, Overdose Emergency Response Committee, Regional Health Authorities, community groups and people who have taken or are taking iOAT and/or TiOAT. 


Full reports are available on request – please contact us for more information.



The iOAT & TiOAT Study has been reviewed and approved by the UBC PHC Research Ethics Board (Reference #H17-01794).


  • Canadian Institutes of Health Research
  • Ministry of Health
  • Dr. Peter Centre
  • British Columbia Centre for Disease Control


Interested in finding out more about the iOAT & TiOAT Study or taking part yourself?

Phone or text: 604-649-9451

Email: [email protected]

BC Centre on Substance Use

400-1045 Howe St, Vancouver, BC V6Z 2A9

E: [email protected] | T: (778) 945-7616 | F: (604) 428-5183

24/7 Addiction Clinician Support Line: (778) 945-7619

Online Addiction Medicine Diploma: [email protected].

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