FDA approves gabapentin once-daily for post-herpetic neuralgia

FDA has approved gabapentin (Gralise, Depomed and Abbott Products) tablets for once-daily treatment of post-herpetic neuralgia (PHN).

“Approval of once-daily gabapentin will not likely cause a significant change in the use of this agent for treating PHN, due to its potentially higher cost and high pill burden,” said Michele B. Kaufman, PharmD, clinical pharmacist, New York Downtown Hospital, New York, and president, PRN Communications Inc.

Gralise is to be titrated over a 2-week period to a once-daily dose of 1,800 mg, given with the evening meal. Its manufacturer currently expects Gralise to be available in 300 mg and 600 mg tablets later this year.

“In order to dose patients up to 1,800 mg a day [over 2 weeks], patients may require 3 to 6 tablets as a final dose. If they experience intolerable side effects, patients will most likely discontinue therapy,” Kaufman told Drug Topics. “The only major advantage to this formulation over previously available gabapentin formulations is the potential for better patient adherence. If approvals for other indications, such as diabetic peripheral neuropathy, are obtained, managed care formulary uptake may increase.”

FDA previously granted Gralise orphan-drug status for the treatment of PHN. Gralise was approved on the basis of 2 phase 3 trials involving 359 patients treated with Gralise and 364 treated with placebo. Safety was evaluated in all 723 patients and the efficacy assessment was based on the second phase 3 trial, a randomized, double-blind, placebo-controlled study of 452 PHN patients. In this trial, Gralise achieved a statistically significant reduction in average daily pain score compared to placebo. Patients in the study were randomly assigned to 2 treatment arms: placebo or 1,800 mg of Gralise dosed once daily.

A total of 359 patients with PHN have received Gralise at doses up to 1,800 mg once daily during placebo-controlled clinical studies. In these trials, 9.7% of patients treated with Gralise and 6.9% of 364 patients treated with placebo discontinued prematurely due to adverse reactions. In the Gralise treatment group, the most common reason for discontinuation due to adverse reactions was dizziness (10.9%). Of Gralise-treated patients who experienced adverse reactions, the majority of those adverse reactions were either “mild” or “moderate.”