Dear Editor:
The article by Dr. Siegel in the June 2005 edition of your journal [Extended Release Drug Delivery Strategies in Psychiatry: Theory to Practice. Psychiatry 2005 2005;2(6):22–31] was quite a relevant and useful piece. I was particularly interested in the aspects that dealt with substance abuse treatment, which touched on the extended-release injectable form of naltrexone.
Another medication currently in the pipeline is a new, extended-release formulation of buprenorphine, which is a depot form. This depot formulation is an injectable solution that contains tiny biodegradable capsules of buprenorphine. As the capsules disintegrate, it is said that it would be slowly released over several weeks, and it would be administered once every 4 to 6 weeks.
Diversion of medications in substance abuse treatments, whether it be medications like methadone, benzodiazepines, or narcotic analgesics, has been a huge problem. Buprenorphine, a partial opiate agonist, was given FDA approval in October 2002 for treatment of opiate addiction. It is the only opiate addiction therapy drug that can be prescribed in a physician's office; others are dispensed at clinics. There have been safeguards in effect to reduce its diversion, which requires patients to visit their physicians frequently, at least weekly during the induction phase, to obtain the oral form. This can be cumbersome for patients, and hence affects their adherence. This new formulation would increase adherence, as the patients would not be required to come into the physician's office as frequently, and more importantly, diversion of this formulation would be impossible, leading to more favorable outcomes for substance abuse clients.
Another extended-release drug worth mentioning would be the recently approved (2004) extended-release carbamazepine (Equetro), which can be given once daily (nightly), and has less peak/trough variations than the immediate release formulation, and hence less side effects. It is a unique three-bead extended release delivery system. There are no published studies regarding it's use with substance abuse clients, especially in those with alcohol dependency problems, where the immediate-release formulation has been valuable, especially as regards treatment of withdrawal symptoms. The extended-release formulation may prove very valuable with the alcohol dependent patients in the future.
With regards,
Adegboyega Oyemade, MD
Chief Resident
Department of Psychiatry
Albany Medical Center
Albany, New York
References
- 1.National Drug Intelligence Center. Buprenorphine: Potential for Abuse. [7/21/05]. Available at: www.usdoj.gov/ndic/
- 2.Post R. Extended-release carbamazepine.Targeting acute bipolar mania. Current Psychiatry. 2005;4(5):72–83. [Google Scholar]