A cost-effectiveness comparison of desipramine, gabapentin, and pregabalin for treating postherpetic neuralgia

OBJECTIVES: To compare the net health effects and costs resulting from treatment with different first-line postherpetic neuralgia (PHN) medications. DESIGN: Cost-utility analysis using published literature. PARTICIPANTS: Hypothetical cohort of patients aged 60 to 80 with PHN. INTERVENTIONS: Desipramine 100 mg/d, gabapentin 1,800 mg/d, and pregabalin 450 mg/d. MEASUREMENTS: A decision model was designed to describe possible treatment outcomes, including different combinations of analgesia and side effects, during the first 3 months of therapy for moderate to severe PHN. The main outcome was cost per quality-adjusted life-year (QALY) gained. Costs were estimated using the perspective of a third-party payer. Multivariate, univariate, and probabilistic sensitivity analyses were performed, and the time frame of the model was varied to 1-month and 6-month horizons. RESULTS: Desipramine was more effective and less expensive than gabapentin or pregabalin (dominant) under all conditions tested. Gabapentin was more effective than pregabalin but at an incremental cost of $216,000/QALY. Below $140/month, gabapentin became more cost-effective than pregabalin at a threshold of $50,000/QALY, and below $115/month gabapentin dominated pregabalin. CONCLUSION: Desipramine appears to be more effective and less expensive than gabapentin or pregabalin for the treatment of older patients with PHN in whom it is not contraindicated. After its price falls, generic gabapentin will likely be more cost-effective than pregabalin.