ABSTRACT
Opioid substitution treatment (OST) for opioid dependence may be limited by adverse events (AEs). Increasing the range of therapeutic options optimizes outcomes and facilitates patient management. An international, multi-center, two-phase study investigated the efficacy and safety of slow-release oral morphine (SROM) versus methadone in patients receiving methadone therapy for opioid dependence. In phase 1 (two way cross-over, 11 weeks each period) patients were randomized to SROM or methadone oral solution. In phase 2 (25 weeks), patients continued treatment with SROM (group A) or switched from methadone to SROM (group B). In total, 211 out of 276 completed phase 1 and 198 entered phase 2 (n=95 group A, n=103 group B). Treatment with both SROM and methadone was well tolerated. However, the mean QTc-interval associated with methadone was significantly longer than that under SROM. Higher treatment satisfaction, fewer cravings for heroin, and lower mental stress were reported with SROM. This study adds a significant further weight of evidence that SROM is an effective and well tolerated long-term maintenance treatment for opioid dependence with a beneficial risk profile compared to methadone regarding cardiac effects and supports its clinical utility.
Subject(s)
Methadone/therapeutic use , Morphine/therapeutic use , Opiate Substitution Treatment , Opioid-Related Disorders/drug therapy , Administration, Oral , Adult , Cross-Over Studies , Delayed-Action Preparations , Europe , Female , Humans , International Cooperation , Male , Methadone/administration & dosage , Methadone/adverse effects , Morphine/administration & dosage , Morphine/adverse effects , Treatment OutcomeABSTRACT
OBJECTIVES: Several studies have reported prolonged QTc intervals in patients under methadone maintenance treatment, including development of torsade-de-pointes arrhythmia and death. It is still not clear why some patients develop critical QTc extensions while others do not. METHODS: ECG findings in a convenience sample of 210 methadone-maintained heroin-dependent patients, taking HCV-infection status and methadone dosage into account simultaneously by means of a multiple linear regression model with QTc-interval as the dependent variable. RESULTS: Prolonged QTc-time is associated with hepatitis C infections (p = 0.005) and higher doses of racemic methadone (p = 0.012). CONCLUSION: Infection with hepatitis C increases the likelihood of critical QTc prolongation in patients in methadone maintenance treatment.