It looks like you're using Internet Explorer 11 or older. This website works best with modern browsers such as the latest versions of Chrome, Firefox, Safari, and Edge. If you continue with this browser, you may see unexpected results.
A commercial site. "The Protocol Exchange is an open repository for sharing scientific research protocols. These protocols are posted directly on the Protocol Exchange by authors and are made freely available to the scientific community for use and comment ... Protocols are not peer reviewed or edited by the Nature Protocols team, although they are screened for non-scientific content and for material that might pose a health or biosecurity risk." -- website
This database is a bibliography of controlled trials identified by contributors to the Cochrane Collaboration and others, as part of an international effort to hand search the world's journals and create an unbiased source of data for systematic reviews.
"OpenTrials is a collaboration between Open Knowledge International and Dr Ben Goldacre from the University of Oxford DataLab. It aims to locate, match, and share all publicly accessible data and documents, on all trials conducted, on all medicines and other treatments, globally." -- website