Extended thromboprophylaxis with enoxaparin in acutely ill medical patients with prolonged periods of immobilisation: the EXCLAIM study

Abstract number: OC397

Hull^* R., Schellong† S., Tapson‡ V., Yusen§ R., Monreal¶ M., Samama^** M. M., Turpie†† A. G. G., Wildgoose‡‡ P., Cort‡‡ S.

‡‡Aventis Pharma, USA ‡Duke University Medical Center, USA; ¶Hospital Germans Trias i Pujol, Spain; ††McMaster University, HHSC McMaster Clinic, Canada; ^**Servie d'Hematologie Biologique, France; †Universitätsklinikum Carl Gustav Carus Medizinisch, Germany; ^*University of Calgary, Canada; §Washington University School of Medicine, USA;

Background  

Acutely ill medical patients have a significant risk of developing venous thromboembolism (VTE). Consensus groups recommend that these patients are given appropriate thromboprophylaxis. Thromboprophylaxis with enoxaparin for 10 ± 4 days has been shown to be effective and well tolerated. However, evidence from the MEDENOX study suggests that the risk of VTE extends beyond this period. The objective of the Extended Clinical Prophylaxis in Acutely Ill Medical Patients (EXCLAIM) study is to evaluate the efficacy and safety of extended (4-week) thromboprophylaxis with enoxaparin in acutely ill medical patients.

Methods  

EXCLAIM is a prospective, randomized, double-blind, placebo-controlled, comparative, multicenter study. Approximately 5800 acutely ill medical patients who are immobile for prolonged periods, and therefore at significant risk of developing VTE, will receive enoxaparin, 40 mg s.c. once daily in an open-label treatment period of 10 ± 4 days. Patients will then be randomized in a double-blind manner to receive either enoxaparin, 40 mg s.c. once daily or placebo for an extended period of 28 ± 4 days. The primary efficacy endpoint is the rate of VTE during the 28 ± 4 days following randomization. Secondary endpoints include the rate of VTE at 3 months from the time of enrolment, and the rate of mortality up to 6 months after entry to the study. The primary safety endpoint is the incidence of major hemorrhagic complications during the 28 ± 4 days after randomization. Proximal deep-vein thrombosis is detected using a standardized ultrasound protocol by blinded local sonographers who receive training and are certified for the study. Ultrasound images are then read by a blinded central committee.

Results  

The primary diagnoses of patients currently enrolled in the study (n = 294) are shown in the table. To date, the average duration of open-label treatment is 7.2 days (range: 0–16 days) and the average duration of double-blind treatment is 23.6 days (range: 0–34 days)

Conclusion  

The EXCLAIM study is currently enrolling a broad range of acutely ill medical patients. Preliminary results demonstrate the feasibility of conducting such a large-scale clinical study using a standardized ultrasound protocol for diagnosing proximal DVT. We anticipate presenting data from the first 1000 patients.

Table 1