Interpretation of Benefit-Risk of Enoxaparin as Comparator in the RECORD Program: Rivaroxaban Oral Tablets (10 milligrams) for Use in Prophylaxis in Deep Vein Thrombosis and Pulmonary Embolism in Patients Undergoing Hip or Knee Replacement Surgery

The Regulation of Coagulation in Major Orthopedic surgery reducing the Risk of DVT and PE (RECORD) clinical program of rivaroxaban consists of 4 phase III clinical trials comparing rivaroxaban with enoxaparin for the prevention of venous thromboembolism (VTE) in patients undergoing either total hip or total knee replacement surgery. Despite the comprehensive and extensive nature of this program, it had some logistic issues that included the dosing of the enoxaparin which was not only inconsistent with the recommendations but the dosages used were not optimal. The duration of treatment while consistent with rivaroxaban did vary with enoxaparin and was somewhat short. The bleeding definitions and safety evaluations were not consistent in accordance with the current recommendations. Moreover, the RECORD program has no power to show differences in major bleeding. The cardiovascular rebound phenomenon should have been adequately addressed and may require additional clinical validation to establish the safety of rivaroxaban. Although the US Food and Drug Administration (FDA) advisory committee has recommended approval of rivaroxaban, the reported analysis strongly suggests additional clinical validation on the claimed benefit/risk ratio of this monotherapeutic anticoagulant.