Inhalational drug delivery in pulmonary aspergillosis

Pulmonary infections have long represented one of the major threats to humans. These vary from acute to chronic conditions, depending upon the underlying disease of the airways. Pulmonary aspergillosis (PMAP) has raised vital concerns in the immunocompromised patients. The fungal infection is difficult to diagnose in the early stages, often making the disease more complicated. Currently, three classes of antifungal agents are available on the market for the treatment of pulmonary infections. These agents are available in oral and intravenous forms only, which limits the availability of therapeutic concentrations of drug in the lungs for longer durations. Consequently, this leads to therapeutic failure and/or resistance of the organism(s) towards the antifungal agents because the optimum amount of drug does not reach the infection site. To combat the issues associated with the conventional regimens, inhalation of antifungal agents is gaining importance because administration to the lungs offers huge advantages of localized and targeted delivery. A wide range of inhalational devices such as nebulizers, dry powder inhalers, and metered dose inhalers are available on the market to deliver drug molecules to the lungs effectively. However, their clinical utility is limited to conditions such as asthma, chronic obstructive pulmonary disease, and cystic fibrosis only. For a few decades, inhalation therapy has also been gaining importance to treat infectious diseases such as tuberculosis and aspergillosis, though more research efforts are required to make the transition from bench to bedside. The current review provides an explicit account of the potential role of inhalation drug delivery in PMAP.