General Information

Gralise is an extended release formulation of the approved drug gabapentin, developed on DepoMed's Gastric Retention technology. Gabapentin is a gamma-aminobutyric acid (GABA), analogue. The mechanism of action by which gabapentin exerts its analgesic action is unknown but in animal models of analgesia, gabapentin prevents allodynia (pain-related behavior in response to a normally innocuous stimulus) and hyperalgesia (exaggerated response to painful stimuli).

Gralise is specifically indicated for the management of postherpetic neuralgia.

Gralise is supplied as a tablet for oral administration. Gralise should be tirated to an 1800 mg dose taken orally once daily with the evening meal. The recommended titration schedule is Day 1: 300mg; Day 2: 600mg; Days 3-6: 900mg; Days 7-10: 1200mg; Days 11-14: 1500mg and Day 15: 1800mg.

Clinical Results

FDA Approval
The FDA approval of Gralise was based on a double-blind, placebo-controlled, multicenter study. This study enrolled 452 subjects between the age of 21 to 89 with postherpetic neuralgia persisting for at least 6 months and compared Gralise 1800 mg once daily with placebo for 11 weeks. Double-blind treatment began with titration starting at 300 mg/day and titrated up to a total daily dose of 1800 mg over 2 weeks, followed by 8 weeks fixed dosing at 1800 mg once daily, and then 1 week of dose tapering. During the 8-week stable dosing period, patients took 3 active or placebo tablets each night with the evening meal. During baseline and treatment, patients recorded their pain in a daily diary using an 11-point numeric pain rating scale. The mean baseline pain score was 6.6 and 6.5 for Gralise and placebo-treated patients, respectively. Treatment with Gralise statistically significantly improved the endpoint mean pain score from baseline.

Side Effects

Adverse events associated with the use of Gralise may include, but are not limited to, the following:

• dizziness
• somnolence
• headache
• peripheral edema
• diarrhea

Mechanism of Action

Gralise is an extended release formulation of the approved drug gabapentin, developed on DepoMed's Gastric Retention technology. Gabapentin is a gamma-aminobutyric acid (GABA), analogue. The mechanism of action by which gabapentin exerts its analgesic action is unknown but in animal models of analgesia, gabapentin prevents allodynia (pain-related behavior in response to a normally innocuous stimulus) and hyperalgesia (exaggerated response to painful stimuli).

Literature References

Wallace MS, Irving G, Cowles VE Gabapentin extended-release tablets for the treatment of patients with postherpetic neuralgia: a randomized, double-blind, placebo-controlled, multicentre study. Clinical Drug Investigation 2010;30(11):765-76

Irving G, Jensen M, Cramer M, Wu J, Chiang YK, Tark M, Wallace M Efficacy and tolerability of gastric-retentive gabapentin for the treatment of postherpetic neuralgia: results of a double-blind, randomized, placebo-controlled clinical trial. The Clinical Journal of Pain 2009 Mar-Apr;25(3):185-92

Additional Information

For additional information regarding Gralise or postherpetic neuralgia, please visit the Depomed web page.