Journal of Alcoholism & Drug Dependence
Open Access

Evaluating the Effectiveness of Buprenorphine-Naloxone Therapy in Opioid Use Disorder: A Multi-Center Cohort Study

Thiago Martins Silva^{* *}Correspondence: Thiago Martins Silva, Department of Addiction Recovery and Mental Health, University of Lisbon Medical Center, Lisbon, Portugal, Email:

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About the Study

The opioid crisis has escalated into a global public health emergency, with Brazil witnessing a steady increase in opioid misuse and related fatalities. Amid this challenge, buprenorphine-naloxone combination therapy has emerged as a cornerstone pharmacological intervention for Opioid Use Disorder (OUD). The formulation combines buprenorphine, a partial opioid agonist, with naloxone, an opioid antagonist, to reduce misuse potential while maintaining therapeutic efficacy. This multi-center cohort study was conducted across five urban hospitals in Brazil and aimed to evaluate the effectiveness of buprenorphine-naloxone therapy in achieving sustained abstinence, improving treatment retention, and reducing relapse rates among individuals diagnosed with moderate to severe.

The study enrolled 468 adult patients (aged 18-65) with a confirmed diagnosis of (Opioid Use Disorder) OUD as per DSM-5 criteria. Participants were divided into two groups: those receiving buprenorphine-naloxone as part of a structured outpatient program, and a control group receiving methadone-based maintenance therapy. Treatment duration was 12 months, with clinical assessments, urine toxicology screens, and psychosocial evaluations performed at baseline, 3, 6, 9, and 12 months. The buprenorphine-naloxone regimen followed Brazilian Ministry of Health guidelines, with induction initiated under supervision and dose adjustments tailored based on patient response. Adjunct behavioral therapy and peer support groups were made available to all participants to simulate a real-world clinical setting.

The primary outcome measure was sustained opioid abstinence, verified by monthly urine screens and self-reports. Secondary outcomes included treatment retention, reduction in opioid cravings, improvement in quality of life, and occurrence of adverse events. Results demonstrated that 71.8% of patients in the buprenorphine-naloxone group achieved sustained abstinence at 12 months, compared to 54.5% in the methadone group. Notably, treatment retention was also higher in the buprenorphine-naloxone cohort, with a 12-month retention rate of 64.1%, significantly surpassing the 47.3% observed in the control group.

Adverse events related to the buprenorphine-naloxone therapy were generally mild and manageable, with nausea, headache, and insomnia being the most frequently reported side effects. Importantly, there were no recorded incidents of respiratory depression or misuse, validating the safety profile of the medication when used in combination with naloxone. In contrast, the methadone group exhibited a higher incidence of side effects, including sedation and constipation, and a small number of non-fatal overdose events. Furthermore, diversion rates, an ongoing concern with opioid treatment programs were substantially lower in the buprenorphine-naloxone group, likely due to the abuse-deterrent properties of the formulation.

Qualitative feedback from participants emphasized the acceptability and convenience of buprenorphine-naloxone, particularly the sublingual film format and reduced stigma compared to methadone clinic visits. This suggests that patient perception plays a vital role in adherence and overall success. Additionally, clinicians reported improved ease of titration and a more favorable therapeutic alliance, attributing these to the predictable pharmacokinetics and lower risk profile of buprenorphine-naloxone.

While the results are promising, the study is not without limitations. Its observational design and reliance on self-reported data may introduce bias, and the sample was limited to urban populations with access to specialized addiction services. Future randomized controlled trials are necessary to confirm causality and explore effectiveness across different socioeconomic settings. Nonetheless, the real-world clinical context and multi-center participation enhance the generalizability of the findings.

In conclusion, this cohort study reinforces the effectiveness of buprenorphine-naloxone therapy in managing opioid use disorder within Brazil’s evolving healthcare landscape. Compared to methadone maintenance, buprenorphine-naloxone demonstrated superior outcomes in promoting abstinence, improving retention, and reducing cravings with fewer side effects and lower misuse potential. These findings are also aids to support the broader adoption of buprenorphine-naloxone as a first-line treatment for Opioid Use Disorder (OUD), particularly in outpatient settings where flexibility, safety, and long-term adherence are paramount. Integrating this therapy into national addiction care protocols, accompanied by behavioral interventions and community support, could significantly enhance Brazil’s response to the opioid crisis and provide a model for other middle-income countries grappling with similar challenges.