The SALOME study: recruitment experiences in a clinical trial offering injectable diacetylmorphine and hydromorphone for opioid dependency

BACKGROUND: The Study to Assess Long-term Opioid Medication Effectiveness (SALOME) is a two-stage phase III, single site (Vancouver, Canada), randomized, double blind controlled trial designed to test if hydromorphone is as effective as diacetylmorphine for the treatment of long-term illicit opioid injection. Recruiting participants for clinical trials continues to be a challenge in medical and addiction research, with many studies not being able to reach the planned sample size in a timely manner. The aim of this study is to describe the recruitment strategies in SALOME, which offered appealing treatments but had limited clinic capacity and no guaranteed post-trial continuation of the treatments. METHODS: SALOME included chronic opioid-dependent, current illicit injection opioid users who had at least one previous episode of opioid maintenance treatment. Regulatory approvals were received in June 2011 and recruitment strategies were implemented over the next 5 months. Recruitment strategies included ongoing open communication with the community, a consistent and accessible team and participant-centered screening. All applicants completed a pre-screening checklist to assess prerequisites. Applicants meeting these prerequisites were later contacted to commence the screening process. RESULTS: A total of 598 applications were received over the two-year recruitment period; 130 were received on the first day of recruitment. Of these applicants, 485 met prerequisites; however, many could not be found or were not reached before recruitment ended. For the 253 candidates who initiated the screening process, the average time lapse between application and screening date was 8.3 months (standard deviation [SD] = 4.44) and for the 202 randomized to the study, the average processing time from initial screen to randomization was 25.9 days (SD = 37.48; Median = 15.0). CONCLUSIONS: As in prior trials offering injectable diacetylmorphine within a supervised model, recruiting participants for this study took longer than planned. The recruitment challenges overcome in SALOME were due to the high number of applicants compared with the limited number that could be randomized and treated. Our study emphasizes the value of integrating these strategies into clinical addiction research to overcome study-specific barriers. TRIAL REGISTRATION: ClinicalTrials.gov: NCT01447212.