Vaccine pharmacotherapy for the treatment of cocaine dependence

Background: Cocaine abuse has no established pharmacotherapy, but active immunotherapy with a cocaine vaccine shows promise as a therapeutic intervention. Methods. An open label, fourteen week, dose-escalation study evaluated the safety, immunogenicity, and clinical efficacy of a novel human cocaine vaccine (TA-CD) in eighteen cocaine dependent subjects. Ten subjects (400 mu g total dose group) received four-100 mu g injections over the course of eight weeks. Subsequently, eight subjects (2000 mu g total dose group) received five-400 mu g vaccinations over twelve weeks. Intent to treat analysis of thrice weekly urine toxicologies and cocaine antibody titers were compared. Results: Sixteen of 18 subjects completed the study. There were no serious adverse reactions and the vaccine was well tolerated. The 2000 mu g total dose group bad a significantly higher mean antibody titer response (2000 units) as compared to the 400 mu g total dose group (1000 units) (p =.05). The 2000 mu g group was more likely to maintain cocaine free urines than those in the 400 mu g group (Z = -3-12, P =.002). Despite relapse in both groups, most reported an attenuation of cocaine's usual euphoric of follow-up time points (63016 in the 400 jig and 100% in the 2000 mu g groups). Conclusions: The conlugated cocaine vaccine was well tolerated and cocaine specific antibodies persisted at least six months. The likelihood of using cocaine decreased in subjects who received the more intense vaccination schedule.