Pregabalin as mono- or add-on therapy for patients with refractory chronic neuropathic pain: a post-marketing prescription-event monitoring study.

This observational study examined the outcome of two different therapeutic strategies in the treatment of chronic neuropathic pain by including pregabalin (PGB) as mono- or add-on therapy in one of two treatment options. Patients with a pain score of > or =4, refractory to usual care for neuropathic pain for at least 6 months, were allocated consecutively to one of two treatment strategies according to the decision of the physician: complete switch to a flexible-dosage, monotherapeutic or add-on therapy with pregabalin (PGB group), or change established doses and combinations of pre-existing mono- or combination therapy without pregabalin (non-PGB group). After 4 weeks (primary endpoint) a significant improvement in pain reduction was documented in both intention-to treat (ITT) analysis (PGB group, n = 85: mean pain score reduction of 3.53, SD 2.03, p < 0.001; non-PGB group, n = 102; mean pain score reduction of 2.83, SD 2.23, p < 0.001) and per-protocol (PP) analysis (PGB group, n = 79: mean pain score reduction 3.53 vs. 2.83, p < 0.05; non-PGB group, n = 81; 3.5 vs. 2.9, p < 0.05) compared to baseline. Comparison of the results observed in the two groups shows that patients in the PGB group achieved significantly greater pain reduction. These results demonstrate that PGB administered twice daily is superior to treatment regimes without PGB in reducing pain and pain-related interference in quality of life.