We disagree that crowdfunding of clinical trials is ethically questionable (P. Y. Cheah Nature 527, 446; 2015). Participants are still governed by the same high standards of research integrity as traditionally funded recipients — but with the added scrutiny that comes with public engagement (see, for example, N. Siva Lancet 384, 1085–1086; 2014).

Cheah criticizes crowdfunding of clinical trials because it risks backing studies that are of limited importance and applicability. However, it is this very feature that offers an opportunity to fund trials for rare or emerging tropical diseases that might not otherwise attract financial support (see, for example, T. S. van der Werf et al. Bull. World Health Organ. 83, 785–791; 2005).