"A number of clinical trials have established the effectiveness of buprenorphine for the maintenance treatment of opioid addiction. These have included studies that compared buprenorphine to placebo (Johnson et al. 1995; Ling et al. 1998; Fudala et al. 2003), as well as comparisons to methadone (e.g., Johnson et al. 1992; Ling et al. 1996; Pani et al. 2000; Petitjean et al. 2001; Schottenfeld et al. 1997; Strain et al. 1994a, 1994b) and to methadone and levo-alpha-acetyl-methadol (LAAM) (Johnson et al. 2000). Results from these studies suggest that buprenorphine in a dose range of 8–16 mg a day sublingually is as clinically effective as approximately 60 mg a day of oral methadone, although it is unlikely to be as effective as full therapeutic doses of methadone (e.g., 120 mg per day) in patients requiring higher levels of full agonist activity for effective treatment.

"A meta-analysis comparing buprenorphine to methadone (Barnett et al. 2001) concluded that buprenorphine was more effective than 20–35 mg of methadone but did not have as robust an effect as 50–80 mg methadone -- much the same effects as the individual studies have concluded."

Source

Center for Substance Abuse Treatment, Clinical Guidelines for the Use of Buprenorphine in the Treatment of Opioid Addiction, Treatment Improvement Protocol (TIP) Series 40, DHHS Publication No. (SMA) 04-3939 (Rockville, MD: Substance Abuse and Mental Health Services Administration, 2004), pp. 20-21.
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