 |
 
|
|
The FDA and DEA use a five-level drug scheduling system to characterize compounds deemed to carry risk of misuse and abuse. These categories range in severity from Schedule I, for compounds with no medical indication (e.g. LSD and marijuana), to Schedule IV and V for medically indicated compounds with some abuse potential (e.g. certain hypnotics and analgesics). All scheduled drugs are subject to greater regulatory scrutiny and must meet requirements above and beyond those of typical pharmaceuticals.
Drug scheduling does not follow strictly from the pharmacology of a drug or its planned clinical indication. The final determination of a drug's status is based on a combination of judgment and science. Some recent examples highlight the continuing complexity of drug scheduling and plans for post-marketing risk management in the drug approval process.
-
Oxycontin, a slow-release formulation of oxycodone, was marketed as a narcotic analgesic with potential safety advantages for patients with chronic pain. Once distributed and prescribed, however, it was readily converted for illicit use-creating one of the United States' most significant recent epidemics of drug abuse.
-
Pregabalin, a drug closely related to gabapentin, has been recommended for Schedule IV, a category for drugs with known abuse potential. Pregabalin and gabapentin share a similar mechanism of action, and show efficacy, yet, gabapentin was unscheduled and pregabalin has been recommended for Schedule IV.
-
Tramadol is a central analgesic that is a synthetic analogue of codeine, but is unscheduled, following FDA acceptance of a proposal from the manufacturer to institute a novel post-marketing surveillance program.
-
Ramelteon, the first of a new class of sleep promoting agents, has recently been approved by the FDA as the first non-scheduled drug to treat insomnia.
These four examples highlight the importance of a well-designed pre-marketing program of abuse liability assessments in animal models and in humans, and the need for a well-conceived and well-executed program plan of risk management related to drug abuse. Pre marketing and post-marketing risk assessment plus risk minimization equals what the FDA calls "risk management".
|
|
|
|
