This document describes an FDA review of an Investigational New Drug (IND) application for a new oral anticoagulant. The FDA issued a clinical hold due to missing information about preclinical toxicity studies, clinical trial stopping rules, and compliance with Good Clinical Practice guidelines. The sponsor resolved the issues by conducting additional preclinical studies, revising the clinical trial protocol, and demonstrating appropriate manufacturing controls. The FDA then removed the clinical hold and allowed the clinical trial to proceed.