Efficacy and tolerability of a very low molecular weight heparin compared with standard heparin in patients with unstable angina: A pilot study

Background: Unstable angina is an active thrombotic process that involves t hrombus formation and platelets. It requires a rapid and intensive treatmen t with anticoagulants and antiplatelets. Hypothesis: The aim of the present study was to compare the efficacy of a v ery low molecular weight heparin, OP 2000, with standard heparin in the tre atment of unstable angina. Tolerance and safety were also assessed. Methods: The study population included 120 consecutive hospitalized patient s with unstable angina randomized for treatment with very low molecular wei ght heparin or with standard heparin. The dosage of the study drug was 200 mg intramuscular (IM) the first day followed by 150 mg IM/day. The control drug was standard heparin starting at a dosage of 5,000 UI/ml intravenously (IV) and followed by continuous infusion at an activated partial thrombopl astin time-adjusted dosage. The primary end points were death, acute myocar dial infarction, urgent revascularization, and recurrence of angina. Tolera bility was assessed using bleeding parameters, thrombocytopenia, and allerg ic reactions. Results: Fourteen clinical events were reported in the study group compared with 25 events in the control group (p < 0.05). No adverse events were rep orted in either group. Conclusion: During the acute phase of unstable angina, treatment with a ver y low molecular weight heparin plus aspirin was more effective than treatme nt with standard heparin plus aspirin.