Leishmaniasis in the era of tumor necrosis factor alpha antagonist therapy--a research agenda for Europe.

A number of published case reports suggest an association of tumor necrosis factor (TNF) alpha antagonist use and manifest leishmaniasis. Despite increasing popularity of antagonising TNF alpha for the treatment of autoimmune disorders, systematic research on the risk of opportunistic leishmaniasis in patients receiving these drugs is lacking. This perspective identifies areas of uncertainty regarding the safety profile of TNF alpha antagonist drugs and their clinical use in patients at risk of leishmaniasis. Then, we reflect on how current pharmacovigilance activities in Europe could be enhanced to help reduce these uncertainties. Our aim is to stimulate a debate about this important drug safety issue with potential consequences for patients receiving TNF alpha antagonists living in or travelling to areas endemic for leishmaniasis.