Extended-duration thromboprophylaxis in acutely ill medical patients with recent reduced mobility: Methodology for the EXCLAIM study

Background: Venous thromboembolism (VTE) is a significant cause of mortality and morbidity in medical patients. Although thromboprophylaxis with enoxaparin reduces the risk of VTE in these patients, the optimal duration of therapy is not currently known. The EXCLAIM (EXtended CLinical prophylaxis in Acutely Ill Medical patients) study is designed to compare the efficacy and safety of extended-duration thromboprophylaxis using enoxaparin with the standard regimen of enoxaparin in acutely ill medical patients with recent reduced mobility. Methods: All enrolled acutely ill medical patients receive enoxaparin 40 mg subcutaneously once daily for 10 +/- 4 days. Eligible patients are then randomized in a blinded manner to receive either extended-duration thromboprophylaxis with enoxaparin 40 mg subcutaneously once daily or placebo subcutaneously once daily for an additional 28 +/- 4 days. The primary efficacy endpoint is the incidence of VTE during the 28 +/- 4 days after randomization. This study utilizes a standardized bilateral compression ultrasonography examination protocol that consists of an intensive interrogation of the deep veins of the lower extremities for proximal deep-vein thrombosis. The secondary efficacy endpoints are the rate of symptomatic VTE during the 3 months after randomization and mortality at 3 and 6 months after enrollment. The primary safety endpoint is the incidence of major hemorrhagic complications during the 28 +/- 4 days after randomization. Results: To date, 3,983 patients, with a broad range of medical conditions, have been included in the study. Almost one third of the enrolled patients with reduced mobility are acutely ill due to respiratory insufficiency and one third have infectious diseases. Conclusions: The EXCLAIM study is designed to show the efficacy and safety of extended-duration thromboprophylaxis using enoxaparin in acutely ill medical patients with recent reduced mobility, which may potentially lead to a reduction in the incidence of late VTE events in these patients.