This article, by Yih-Ing Hser, Andrew Saxon (of the Pacific Northwest Node), David Huang, and colleagues, reports on a secondary analysis of data from National Drug Abuse Treatment Clinical Trials Network protocol CTN-0027 (“Starting Treatment with Agonist Replacement Therapies (START)“). It examined patient and medication characteristics associated with retention and continued illicit opioid use in methadone (MET) versus buprenorphine/naloxone (BUP) treatment for opioid dependence.
The differences between the two medications were significant — the treatment completion rate was 74% for MET vs. only 46% for BUP, with the rate for MET participants increasing to 80% when the maximum methadone dose reached or exceeded 60mg/day. With buprenorphine, the completion rate also increased with higher doses, but still only reached 60% at maximum dosage.
Buprenorphine treatment, on the other hand, was associated with significantly lower positive opioid urine test results than methadone in the first 9 weeks of treatment.
The study found 4 clear factors associated with treatment drop-out in this population: 1. Administration of BUP instead of MET; 2. Lower medication dose (<15 for BUP, <60 for MET); 3. The interaction of dose and treatment condition (those with higher BUP dose were 1.04 times more likely to drop out than those with lower MET dose); and 4. Being younger, Hispanic, and using heroin or other substances during treatment.
Conclusions: Provision of methadone appears to be associated with better retention in treatment for opioid dependence than buprenorphine, as does provision of higher doses of both medications. However, provision of buprenorphine is associated with lower continued use of illicit opioids. The high dropout rates at the early phase of buprenorphine treatment suggest the need for early interventions to increase retention for BUP patients.
Citation: Hser Y, Saxon AJ, Huang D, et al. Treatment Retention Among Patients Randomized to Buprenorphine/Naloxone Compared to Methadone in a Multi-Site Trial. Addiction 2013 (in press).