The treaty updated the Paris Convention of 13 July 1931, to include the vast number of synthetic opioids invented in the intervening 30 years and to add a mechanism for more easily including new ones. From 1931 to 1961, most of the families of synthetic opioids had been developed, including drugs related to methadone, pethidine (meperidine/Demerol), morphinans, and dextromoramide (Palfium, Palphium, Jetrium, Dimorlin, marketed solely in the Netherlands). Research on fentanyls and piritramide (R-3365, Pirium, Dipidolor, Piridolan, among others) was also nearing fruition at that point.
