Gabapentin enacarbil
Encyclopedia
Gabapentin enacarbil is a prodrug
for the anticonvulsant
and analgesic
drug gabapentin
. It was designed for increased oral bioavailability
over gabapentin, and human trials showed it to produce extended release of gabapentin with almost twice the overall bioavailability, especially when taken with a fatty meal. Gabapentin enacarbil has passed human clinical trial
s for the treatment of restless legs syndrome
, and initial results have shown it to be well tolerated and reasonably effective.
Gabapentin enacarbil was denied approval by the U.S. Food and Drug Administration
(FDA) in February 2010, citing concerns about possible increased cancer risk shown by some animal studies. Similar concerns had been raised about gabapentin itself in the past, but were felt to be outweighed by its clinical utility as an anticonvulsant, whereas the treatment of restless legs syndrome was not seen to justify the same kind of risk.
On April 6, 2011, Xenoport received FDA approval for Horizant (gabapentin enacarbil) for the treatment of moderate-to-severe restless legs syndrome.
Prodrug
A prodrug is a pharmacological substance administered in an inactive form. Once administered, the prodrug is metabolised in vivo into an active metabolite, a process termed bioactivation. The rationale behind the use of a prodrug is generally for absorption, distribution, metabolism, and...
for the anticonvulsant
Anticonvulsant
The anticonvulsants are a diverse group of pharmaceuticals used in the treatment of epileptic seizures. Anticonvulsants are also increasingly being used in the treatment of bipolar disorder, since many seem to act as mood stabilizers, and in the treatment of neuropathic pain. The goal of an...
and analgesic
Analgesic
An analgesic is any member of the group of drugs used to relieve pain . The word analgesic derives from Greek an- and algos ....
drug gabapentin
Gabapentin
Gabapentin is a pharmaceutical drug, specifically a GABA analogue. It was originally developed for the treatment of epilepsy, and currently is also used to relieve neuropathic pain...
. It was designed for increased oral bioavailability
Bioavailability
In pharmacology, bioavailability is a subcategory of absorption and is used to describe the fraction of an administered dose of unchanged drug that reaches the systemic circulation, one of the principal pharmacokinetic properties of drugs. By definition, when a medication is administered...
over gabapentin, and human trials showed it to produce extended release of gabapentin with almost twice the overall bioavailability, especially when taken with a fatty meal. Gabapentin enacarbil has passed human clinical trial
Clinical trial
Clinical trials are a set of procedures in medical research and drug development that are conducted to allow safety and efficacy data to be collected for health interventions...
s for the treatment of restless legs syndrome
Restless legs syndrome
Restless legs syndrome or Willis-Ekbom disease is a neurological disorder characterized by an irresistible urge to move one's body to stop uncomfortable or odd sensations. It most commonly affects the legs, but can affect the arms, torso, and even phantom limbs...
, and initial results have shown it to be well tolerated and reasonably effective.
Gabapentin enacarbil was denied approval by the U.S. Food and Drug Administration
Food and Drug Administration
The Food and Drug Administration is an agency of the United States Department of Health and Human Services, one of the United States federal executive departments...
(FDA) in February 2010, citing concerns about possible increased cancer risk shown by some animal studies. Similar concerns had been raised about gabapentin itself in the past, but were felt to be outweighed by its clinical utility as an anticonvulsant, whereas the treatment of restless legs syndrome was not seen to justify the same kind of risk.
On April 6, 2011, Xenoport received FDA approval for Horizant (gabapentin enacarbil) for the treatment of moderate-to-severe restless legs syndrome.