"NIDA has developed buprenorphine [Subutex or Suboxone when combined with naloxone] that has much less potent effects than heroin, morphine or Demerol [meperidine]," said Volkow. "It is an opiate that has analgesic properties. We are going to be launching a large clinical trial to evaluate the benefit of this medication in the treatment of individuals who have pain but are also addicted to opiate analgesics."
According to Vocci, the protocol for the clinical trial is being developed. The trial is expected to be underway in the summer of 2005.
Vocci was asked what other medications besides buprenorphine are being developed to treat problems of addiction to opioid analgesics. One approach is a "depot" formulation of naltrexone (ReVia), an opiate receptor antagonist. The oral form of naltrexone is indicated for use in the treatment of alcohol dependence and for the blockade of exogenously administered opioids.
The depot formulation, currently being studied for treatment of alcoholism, was studied by NIDA for opiate addiction. "We actually funded three separate companies to do research on it," Vocci said, and at least one of the companies is clearly working toward a drug application with the FDA.
Another drug being developed with NIDA's help is called lofexidine. Lofexidine is an -2 adrenergic agonist that is increasingly used in the management of opiate withdrawal--notably in the United Kingdom.
"We have done one major clinical trial with it, and we are going to help a company develop a second major clinical trial," Vocci said. "We will start between April and June of 2005. The sites are still being picked, and we are determining who the lead researcher will be."
Vocci was asked what psychiatrists could be doing to help reduce prescription drug abuse. He said they need to "be aware of the addiction potential of certain drugs," and they could become more educated about dealing with individuals who have histories of drug abuse, adding that he would like to see more psychiatrists move into treatment of addictions as a subspecialty.
For physicians, generally, Vocci said they need to identify patients with prior histories of any kind of substance abuse. If years ago a patient drank too much or abused amphetamines or other drugs then that patient may have problems with prescription opiates.
