ORN Fall 2026 - Pharmacokinetics and breast milk transfer of naltrexone and extended-release buprenorphine in pregnant and lactating individuals with substance use disorders.-2026-09-02

Video Transcription

Video Summary

This webinar, hosted by the Opioid Response Network and sponsored by SAMHSA, featured Dr. Alicia Walkman discussing emerging evidence on naltrexone and extended-release buprenorphine in pregnant and lactating individuals with substance use disorders.<br /><br />She reviewed Boston Medical Center’s work with a high-risk, underserved population and described studies evaluating medication for opioid use disorder (MOUD) during pregnancy, postpartum, and breastfeeding. For naltrexone, she explained that both oral and extended-release formulations are being studied as options for patients with opioid and alcohol use disorder. While data in pregnancy remain limited, available retrospective and prospective studies were reassuring, showing no major safety concerns, low rates of neonatal opioid withdrawal, and acceptable pharmacokinetics. Her team’s small prospective study found no return to opioid use during follow-up and no neonatal opioid withdrawal in exposed infants.<br /><br />She then discussed extended-release buprenorphine, including Sublocade and Brixadi/CAM2038. Concern has existed about the excipient NMP, but growing clinical use and recent studies have been reassuring. The MOMS study found higher illicit opioid abstinence during pregnancy with extended-release buprenorphine, similar postpartum outcomes, and no difference in neonatal opioid withdrawal severity.<br /><br />Dr. Walkman also summarized lactation data. Buprenorphine and naltrexone appear in breast milk at very low levels, with low relative infant doses and no infant plasma exposure of concern in the limited studies available. Breastfeeding in this population was associated with improved maternal recovery outcomes, likely reflecting parental presence, bonding, and engagement in care.<br /><br />She concluded that naltrexone and extended-release buprenorphine are promising emerging options in perinatal addiction care, but more research is needed to guide safe and effective treatment.

Keywords

naltrexone

extended-release buprenorphine

pregnancy

lactation

opioid use disorder

substance use disorders

medication for opioid use disorder

neonatal opioid withdrawal

breastfeeding

perinatal addiction care