Abstract: For the economic purpose of clinical trial and study of safety and immunogenicity of therapeutic morphine vaccine, 102 out of 200 outpatient volunteer addicts, whom were interested in abstinence, were injected with morphine vaccine, by randomized double blind method and under placebo control. The volunteers were divided into 3 cohorts, each consists of 30 subjects. The cohorts 1, 2 and 3 were injected with 12.5, 100 and 600 μg mL-1 of morphine vaccine, respectively. In each cohort, four additional subjects were injected with placebo. All the volunteers were bled prior to each injection and they got intra deltoid injections at 0-30-60 days and were monitored for safety and antibody production, for 12 months. All of 102 volunteers completed the course of three injections and all of them returned for the final scheduled visit at day 90th. The rise of antibody against morphine in all three vaccinated cohorts was controlled along the 5, 7, 9, 11 and 12 months. The vaccine was well tolerated with dose related increases in antibody levels and had no serious drug-related adverse events. Only 5 persons at the highest dose experienced brief post injection twitching. Anti-morphine antibody was detected by ELISA method after the first injection of 100, 600 μg mL-1 and second injection of 12.5 μg mL-1 doses and reached to its peak in 3 months and did not decline to baseline after one year. Thus, vaccine was well tolerated with dose related increases in antibody levels and a high proportion of outpatient volunteer addicts were recovered.