Grant: Project Grant

Injection drug use is a key risk factor for overdose death, so preventing people from initiating injection drug use would reduce the unacceptably high death toll due to the opioid overdose epidemic. At present, though, there are no effective and scalable approaches to preventing people from starting to inject drugs. However, research does indicate that people who already inject drugs play a critical role in facilitating the entry of others into injecting. Emerging evidence also suggests that enrolling people who inject drugs into medication-assisted treatment for opioid use disorder (e.g., methadone or buprenorphine) may reduce their risk of initiating others into drug injecting. The overall goal of this project is therefore to investigate whether enrolling people who inject drugs in medication-assisted treatment can help them reduce their risk of assisting others into drug injecting, and to determine how effective, adaptable and scalable this approach to preventing injection drug use can be across different settings. This study -- known as PRIMER II (Preventing Injecting by Modifying Existing Responses) -- achieves this goal by pooling data from 5 cohort studies of people who inject drugs across North America in 6 different settings. These include cohort studies in Vancouver and Toronto; Baltimore, Rural Kentucky, and San Diego (USA); and Tijuana, Mexico, which collectively provide data from approximately 5,000 participants, making this the largest study of injection initiation to date.