Treatment of postherpetic neuralgia with pregabalin under clinical practice conditions

Postherpetic neuralgia (PHN) profoundly affects health-related quality of life and functional status of patients. In addition to pain, often sleep disturbances or anxiety/depression are present (“triad of pain“). While the prevalence of PHN in herpes zoster patients is high (ca. 11%), it is difficult to treat and often refractory to available therapies. Pregabalin, a highly selective ligand for the alpha2-delta subunit protein of voltage-gated calcium channels, reduces release of excitatory neurotransmitters. It is approved for, among other indications, the treatment of peripheral and central neuropathic pain. We aimed to assess its efficacy and safety in general practice.

Methods: In a prospective open, observational trial, 5808 physicians treated 15301 patients with peripheral neuropathic pain with pregabalin administered twice-daily in a flexible-dose regimen over a median duration of 45 days. Pain severity, sleep interference and general well-being were assessed on numerical rating scales (0=best, 10=worst value) after 1, 3 and 6 weeks. The Patient Health Questionnaire (PHQ-D) was used to assess depression.

A total of 2817 subjects in the total cohort had PHN. Mean duration of PHN pain since first diagnosis was 1.0 (±1.7) years. During pregabalin treatment (mean dose 301mg/day), the mean (±standard deviation) pain score was reduced from 6.8±1.6at baseline to 4.4±1.8at week 1, to 2.7±1.7at week 3, and to 1.9±1.7at week 6. Response in terms of 30% pain reduction at study end compared to baseline was achieved in 94.0%, and 50% pain reduction in 87.5%. Pain-associated interference with sleep was reduced from 6.0±2.4at baseline to 1.4±1.7at 6 weeks. The proportion of patients with major depression syndrome (in PHQ) decreased from 62.2% to 37.9%. General well-being improved from 6.6±2.1 to 1.7±1.8. Satisfaction with drug efficacy was reported by 95% of physicians and by 93% of patients.

Pregabalin was well tolerated, and 96% of patients were “very satisfied“ or “satisfied“ with tolerability. Most common AEs in the total cohort were dizziness (1.4%), fatigue (1.1%) and somnolence (0.8%).

Patients with PHN responded very well to pregabalin therapy in terms of reduction of pain, sleep disturbances and depression rates, as well as improvement of general well-being. Effects were observed already within week 1. These findings in the general practice setting are in line with results from controlled clinical trials on pregabalin in PHN patients.