In its first human clinical trials, it caused catastrophic systemic organ failures in the subjects, despite being administered at a supposed sub-clinical dose of 0.1 mg per kg, some 500 times lower than the dose found safe in animals. Six volunteers were hospitalized on 13 March 2006, at least four of these suffering from multiple organ dysfunction. Tentative opinions from an as-yet uncompleted inquiry suggest that the problems resulted from "unforeseen biological action in humans", rather than breach of trial protocols, and the case therefore has had important ramifications for future trials of potentially powerful clinical agents.