This website provides information about a clinical study, ROXI-CATH, for adults who have to undergo placement of a venous catheter. Patients with a venous catheter have a risk of developing venous thromboembolism (VTE). ROXI-CATH aims to test two investigational study treatments [(REGN9933 and REGN7508)] that were designed to prevent VTE. The study treatments are called investigational because they are not approved for use outside of clinical trials.