Crisugabalin Alleviates Postherpetic Neuralgia Symptoms in Phase 3 Study

TOPLINE:

Crisugabalin — an oral calcium channel alpha 2 delta-1 subunit ligand — was safe and well-tolerated at doses of 40 mg/d and 80 mg/d and significantly reduced pain scores in patients with postherpetic neuralgia (PHN) over 12 weeks in a phase 3 study.

METHODOLOGY:

• Researchers conducted a phase 3 multicenter, double-blind study involving 366 patients in China (median age, 63 years; 52.7% men) with PHN with an average daily pain score (ADPS) of 4 or greater on the numeric pain rating scale who were randomly assigned to receive either crisugabalin 40 mg/d (n = 121), 80 mg/d (n = 121), or placebo (n = 124) for 12 weeks.
• Patients who did not experience any serious toxic effects in these 12 weeks entered a 14-week open-label extension phase and received crisugabalin 40 mg twice daily.
• The primary efficacy endpoint was the change in ADPS from baseline at week 12.
• Secondary efficacy endpoints included the proportion of patients achieving at least 30% and 50% reduction in ADPS at week 12; changes in the Short-Form McGill Pain Questionnaire (SF-MPQ), Visual Analog Scale, and Average Daily Sleep Interference Scale scores at week 12; and change in the SF-MPQ Present Pain Intensity scores at weeks 12 and 26.

TAKEAWAY:

• At week 12, among those on crisugabalin 40 mg/d and 80 mg/d, there were significant reductions in ADPS compared with placebo (least squares mean [LSM] change from baseline, −2.2 and −2.6 vs −1.1, respectively; P < .001).
• A greater proportion of patients on crisugabalin 40 mg/d (61.2%) and 80 mg/d (54.5%) achieved 30% or greater reduction in ADPS (P < .001) than patients who received placebo (35.5%). Similarly, a 50% or greater reduction in ADPS was achieved by 37.2% of patients on crisugabalin 40 mg/d (P = .002) and 38% on 80 mg/d (P < .001), compared with 20.2% for placebo.
• Crisugabalin 40 mg/d and crisugabalin 80 mg/d were associated with greater reductions in the pain intensity at week 12 than placebo (LSM, −1.0 and −1.2 vs −0.5, respectively; P < .001). Similar patterns were noted for other pain-related measures at weeks 12 and 26.
• Serious treatment-emergent adverse events occurred in four patients in each group; only 2.4% of those on 40 mg/d and 1.6% on 80 mg/d discontinued treatment because of side effects.

IN PRACTICE:

“Crisugabalin 40 mg/d or crisugabalin 80 mg/d was well-tolerated and significantly improved ADPS compared to placebo,” the authors wrote, adding that “crisugabalin can be flexibly selected depending on individual patient response and tolerability at 40 mg/d or 80 mg/d.”

SOURCE:

The study was led by Daying Zhang, PhD, of the Department of Pain Medicine at The First Affiliated Hospital of Nanchang University, Nanchang, China. It was published online in JAMA Dermatology.

LIMITATIONS:

The findings may not be generalizable to the global population as the study population was limited to Chinese patients. The study only provided short-term efficacy and safety data on crisugabalin, lacked an active comparator, and did not reflect the standard of care observed in the United States or Europe, where oral tricyclic antidepressants, pregabalin, and the lidocaine patch are recommended as first-line therapies.

DISCLOSURES:

The study was sponsored and funded by Haisco Pharmaceutical. Dr. Zhang and another author reported receiving support from Haisco. Two authors are company employees.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication. A version of this article first appeared on Medscape.com.