In a double-blind controlled study, d1-α-acetylmethadol hydrochloride a synthetic congener of methadone hydrochloride with a 72- to 96-hour duration of action was compared to methadone in the treatment of long-term compulsive heroin users. The subjects were ambulatory patients whose conditions were already stabilized with oral administration of methadone. Over a five-week period of observation there were no differences in social adjustment between those patients whose conditions were maintained with a daily methadone regimen and those given d1-α-acetylmethadol three times a week.
Jaffe JH, Schuster CR, Smith BB, Blachley PH. Comparison of Acetylmethadol and Methadone in the Treatment of Long-Term Heroin UsersA Pilot Study. JAMA. 1970;211(11):1834–1836. doi:10.1001/jama.1970.03170110040008