Therapeutic drug monitoring of voriconazole and posaconazole for invasive aspergillosis.

Voriconazole and posaconazole are extended-spectrum triazoles recommended for treatment, prophylaxis and salvage therapy of Aspergillus diseases. Over the past decade many papers have emerged supporting the use of therapeutic drug monitoring (TDM) for azole antifungals. TDM is used to tailor the exposure of a specific drug to the individuals to optimize treatment response and minimize side effects. We reviewed the pharmacokinetics and pharmacodynamics (PK-PD) characteristics of voriconazole and posaconazole. We present the available evidence on target concentrations defining maximal efficacy and minimal toxicity. Finally we provide some practical recommendations how to best perform TDM in clinical practice.