Dose-response of pregabalin for diabetic peripheral neuropathy, postherpetic neuralgia, and fibromyalgia

The pregabalin dose-response for pain, Patient Global Impression of Change (PGIC), and sleep quality measures in painful diabetic peripheral neuropathy (pDPN), postherpetic neuralgia (PHN), and fibromyalgia (FM) is relevant for physicians treating these patients. This analysis aimed to demonstrate the dose-response of pregabalin for each indication and describe the onset (incidence), onset/continuation (prevalence), and resolution of adverse events (AEs) occurring during treatment.

Data from 14 placebo-controlled, fixed-dose pregabalin trials in pDPN, PHN, and FM were pooled within each indication. Patients had mean baseline pain scores ≥6 on an 11-point numeric rating scale. A hyperbolic E_max dose-response model examined the dose-response of pregabalin for pain, PGIC, and sleep quality. Safety assessments included onset and prevalence of common AEs each week, and resolution in the first 2 months of treatment.

In all indications, the likelihood of patients experiencing pain relief and improvements in PGIC and sleep quality increased in a dose-dependent manner with increasing doses. In all indications, new incidences of dizziness and somnolence were highest after 1 week of treatment, with few subsequent new reports at a given dose. Prevalence rates decreased steadily after 1 week of treatment. In FM, new onset weight gain emerged 6-8 weeks following treatment; prevalence rates generally increased then remained steady over time. With the exception of weight gain, many AEs resolved in month 1.

The dose-response of pregabalin for pain, PGIC, and sleep quality was demonstrated, highlighting the benefit of achieving the maximum recommended dose of 300 mg/day for pDPN, 300-600 mg/day for PHN, and 300-450 mg/day for FM. Common AEs are generally seen within 1 week of starting treatment, with few subsequent new reports at a given dose. New onset weight gain occurs after 6 weeks of treatment, reinforcing the need for regular monitoring of weight.