Depomed, Inc. (NASDAQ: DEPO) today announced that a report of Phase 3 data published online this month, ahead of the print edition, in the Clinical Journal of Pain showed that once-daily Gralise® (gabapentin) tablets (1,800 mg) formulation significantly reduces intensity of pain in patients with postherpetic neuralgia (PHN). The results showed that patients treated with Gralise experienced a significant reduction (- 2.12) in their average daily pain intensity compared with placebo treated patients.
The published results are from a randomized, multi-center Phase III clinical study of 452 patients with PHN that evaluated the efficacy and safety of once-daily Gralise compared to placebo. Other results showed that the frequency of adverse events commonly associated with gabapentin was as follows: dizziness (11.3% vs. placebo, 1.7%), somnolence (5.4% vs. placebo 3.0%), and peripheral edema (3.2% vs. placebo, 0.4%) with differences in dizziness and peripheral edema being statistically significant. Secondary endpoints showed that 43% of patients treated with Gralise reported "much" or "very much" improvement compared to 34% of placebo treated patients (P<0.0434).
"Our research shows that patients treated with Gralise experienced significant reduction of their daily pain intensity," said Christine N. Sang, MD, MPH, director of Translational Pain Research, Brigham and Women's Hospital, Harvard Medical School. "This finding is encouraging because the pain associated with PHN has a significant impact on patients' daily lives and these results suggest that Gralise, in part because of its gastroretentive formulation, could fill an important treatment gap for patients with PHN."
The study was an 11-week double-blind, randomized, placebo-controlled Phase III clinical trial which evaluated the efficacy and safety of a once-daily gastroretentive formulation of Gralise (1,800 mg once daily) in patients with postherpetic neuralgia (PHN). The multi-center study evaluated patients with persistent pain for at least six months but not more than five years after the healing of a herpes zoster rash, with a pain intensity score of at least four on the 11-point Numerical Rating Scale (NRS) at screening.
The study's primary endpoint was change in the average daily pain intensity score from the baseline week until week 10 of the study. Secondary endpoints included change in clinician global impression of change (CGIC) and patient global impression of change (PGIC) and post hoc analyses by country.
Once-daily Gralise (1800 mg) was well tolerated in the study, with a lower incidence of common adverse events (AEs) than previously reported in other gabapentin studies. In the Phase III study, 210 patients reported AEs, 118 in the Gralise treated population, and 92 in the placebo treated group. The most common AEs reported included dizziness, headache and nausea. Ten serious AEs (SAEs) were reported, four in the Gralise treated group, and six in the placebo treated group. None of the SAEs were attributable to the study drug.