These animal experiments were so promising that they prompted Dr. Crystal and his team to launch in January 2017 a double-blind clinical trial of the vaccine with human subjects who actively use cocaine and want to quit.
Once participants are selected, researchers will administer a low dose of the vaccine. After the first vaccine, each person will receive a booster shot every four weeks for a total of six injections. Finally, each person will be monitored for three months, with weekly check-ins, until the end of the 32-week study. The entire phase 1 study is expected to take 1½ years.
“Each time the subjects come back — two or three times a week — we test their urine for the drug,” says Dr. Crystal. The plan is to start with 10 users. Seven will get the vaccine; three will get a placebo.
“I don’t know who is getting the vaccine and who isn’t, but the hope is that the people who do will use cocaine less than those getting the placebo,” Dr. Crystal explains, because they won’t feel the drug’s effects.
After the initial group of 10, Dr. Crystal and his team will test the vaccine and placebo on 10 more participants, then a final 10, for a total of 30 subjects. Each one will undergo standard drug dependency therapy throughout the study.
If Dr. Crystal’s trial with human cocaine users is successful, the hope is that this technology could potentially be applied to other addictive substances, such as nicotine or heroin, preventing the scourge of addiction all over the country and even the world.
“We’re thinking of it as a platform strategy,” he says. “We happened to start with cocaine, but if the concept works, we can start thinking about using it with a range of addictive molecules.”
For now, Weill Cornell Medicine and NewYork-Presbyterian/Weill Cornell Medical Center researchers are waiting to see how things evolve as they enroll more subjects and the results start rolling in. “We believe this is an innovative strategy to deal with a major societal problem,” says Dr. Crystal. “If it works, it will be a game-changer.”