First large-scale study to assess treatment for prescription drug addiction

Apr 19 2007

UCSF is launching a new study to evaluate treatments for addiction to prescription painkillers and has openings for patients to enroll.

This is the first large-scale study to assess whether addiction to opioid painkillers, such as Vicodin and OxyContin, can effectively be treated with drug treatments currently used for heroin addiction.

The study is part of a national effort involving 11 clinical research centers to evaluate such therapies. Known as the Prescription Opiate Addiction Treatment Study, or POATS, it is being led by the National Drug Abuse Treatment Clinical Trials Network, under the National Institute of Drug Abuse (NIDA). UCSF is the only study site in Northern California.

The research is in response to the growing national problem of prescription drug abuse that has resulted in higher emergency room admissions and potentially devastating impacts on millions of Americans and their families, according to Stephen Dominy, MD, director of the Division of Substance Abuse and Addiction Medicine at San Francisco General Hospital Medical Center, who is co-leading the UCSF portion of the study.

"The abuse of prescription opiates has become a very serious problem in our society, but until now, there have been no large-scale studies to evaluate how to treat those addictions," Dominy said. "This study hopes to assess whether current opiate dependence therapies are effective, as well as the role of counseling in treatment outcomes."

An estimated 2.2 million Americans aged 12 or older start using prescription pain relievers each year for non-medical uses, surpassing the number of new marijuana users (2.1 million), according to the 2005 National Survey on Drug Use and Health. In that survey, more than 6 million Americans reported using prescription drugs for non-medical uses in the previous month, which is more than the number abusing cocaine, heroin, hallucinogens and inhalants, combined.

Those users, however, seem to fit a very different profile from traditional patients in heroin dependence programs, according to Yong Song, PhD, co-principal investigator for the UCSF site study and an assistant clinical professor of psychiatry in the UCSF School of Medicine. These users tend to be younger, he said, with fewer other dependency issues, such as alcohol or cocaine, and often come from a middle-class background.

"Opiate addiction is well studied in heroin dependence, but very little is known about what treatments are effective with this group of people," Song said. "We think this is a different demographic, but it's not well studied. This trial will confirm whether they really do look different."

The study will test the effectiveness of buprenorphine/naloxone combination tablets, marketed as Suboxone, along with different models of drug counseling in patients addicted to prescription opioids.

Buprenorphine works by acting on the brain's own opiate receptors , targets for heroin, morphine and prescription opioids , to relieve drug cravings without prompting the same intense high or dangerous side effects. When combined with naloxone, buprenorphine's abuse potential is further limited, as those who try to inject it to get high experience severe withdrawal symptoms, while no adverse effects occur when it is taken orally, as prescribed. This combined medication has been approved for prescribing by specially trained physicians in office-based settings, greatly expanding the treatment options available for opiate addiction.

The multi-site study, which seeks to enroll 648 participants, will include people who take prescription drugs for chronic pain and have become addicted to them, as well as those who abuse painkillers for non-medical reasons. UCSF hopes to enroll 54 patients in its site study over the next 18 months.

Subjects enrolled in this study will be treated with the combined drug for one month, after which their dose will be tapered off as part of a detoxification process. If they remain abstinent for two months, they will complete the study. If they relapse and begin abusing prescription opiates again, they may be eligible to re-enter the treatment study.

In addition, to compare the effectiveness of different behavioral therapies in conjunction with the medication, half the subjects will be enrolled in an intensive individualized drug counseling program when they get their prescriptions. The other half will receive a brief drug counseling session from their doctors. Patients will receive all study treatments, including medications, without cost and also will be compensated for their time.