RCT of buprenorphine versus methadone in pregnancy reassuring

Addiction 2006 101;2:275-281

Methadone versus buprenorphine in pregnant addicts: a double-blind, double-dummy comparison study. Fischer G, Ortner R, Rohrmeister K, Jagsch R, Baewert A, Langer M, Aschauer H.

Dear Colleagues,

This small but meaningful study from Vienna gives us further confidence in the safety and effectiveness of (pure) buprenorphine in pregnancy when compared with traditional methadone treatment. These authors performed a randomised, double dummy trial using flexible dosing, daily attendance and psychosocial supports for 18 patients.

They used flexible doses of 8-24mg buprenorphine and 40-100mg methadone in women at 24-29 weeks of pregnancy.

There was a still birth at 38 weeks in a woman who had been abusing opioids, cocaine and benzodiazepines. Another had a late spontaneous abortion at 28 weeks. Both were methadone subjects. Another two patients were withdrawn from the study due to non-compliance (one buprenorphine and one methadone patient).

Of the remaining subjects who went to term, neonatal abstinence syndrome (NAS) was equal across the two groups. Only about 50% of babies needed treatment for NAS (for an average of 5 days in both groups). The signs were noted slightly earlier in the methadone subjects (60 hours; versus 72 hours after birth for buprenorphine). Intercurrent drug use, determined from urine toxicology, was significantly less in the methadone subjects. Retention rates were not significantly different, possibly owing to the low numbers.

Again, these researchers have provided further evidence of the safety and effectiveness of buprenorphine in pregnancy. With a lack of adverse reports and widespread use in many countries, we can probably now prescribe buprenorphine with more confidence for pregnant women in whom methadone has proven unsatisfactory. It is still not 'first line' in my view, but an excellent alternative when indicated. It also is an indirect reminder that the combination drug should never be used in pregnancy or during lactation (and probably ought not to be used in women who are at risk of becoming pregnant since safety data are absent).

Comments by Andrew Byrne ..