Eptifibatide


Eptifibatide, is an antiplatelet drug of the glycoprotein IIb/IIIa inhibitor class. Eptifibatide is a cyclic heptapeptide derived from a disintegrin protein found in the venom of the southeastern pygmy rattlesnake. It belongs to the class of the arginin-glycin-aspartat-mimetics and reversibly binds to platelets. Eptifibatide has a short half-life. The drug is the third inhibitor of GPIIb/IIIa that has found broad acceptance after the specific antibody abciximab and the non-peptide tirofiban entered the global market.
Integrilin is sold in two strengths, globally: vials containing 2 mg/ml and 0.75 mg/ml. A third size is sold in the US: 100 ml vials containing 2 mg/ml.

Indications

Eptifibatide is used to reduce the risk of acute cardiac ischemic events in patients with unstable angina or non-ST-segment-elevation myocardial infarction both in patients who are to receive non surgery medical treatment and those undergoing percutaneous coronary intervention.
The drug is usually applied together with aspirin or clopidogrel and heparin. Additionally, the usual supportive treatment consisting of applications of nitrates, beta-blockers, opioid analgesics and/or benzodiazepines should be employed as indicated. Angiographic evaluation and other intensive diagnostic procedures may be considered a first line task before initiating therapy with eptifibatide.
The drug should exclusively be used in hospitalized patients both because of the serious degree of patients' illness and because of the possible side-effects of eptifibatide.

Contraindications and precautions

Patients receiving eptifibatide are typically seriously ill and most of them are concomitantly treated with other drugs known to have the potential to cause significant side effects. Therefore, not all side effects listed as follows may be attributable to eptifibatide treatment alone:
The major adverse event in the PURSUIT study was severe bleeding. Bleeding occurred as well at sites of clinical intervention as at other sites like urogenital bleeds. Sometimes, these events were severe enough to require transfusion of blood or plasma concentrates to stop bleeding and counteract anemia. Severe bleeds occurred in 4.4 and 4.7% of patients respectively depending on the infusion rate. A few cases of death due to severe bleeding events attributable to drug therapy were reported. No cases of hemorrhagic stroke were seen. Thrombocytopenia of unknown origin was also noticed in 0.2% of patients.
Additionally, hypotension was seen frequently. Cardiovascular failure was also frequent as were serious arrhythmias. Severe allergic reactions occurred in almost 0.2% of patients. These reactions can be life-threatening and may be due to the peptide character of eptifibatide. Other side effects were rare and mild in nature and may not be connected to eptifibatide therapy.

Dosage regimen

The recommended adult dosage is an i.v. loading dose of 180 µg/kg over 1 to 2 minutes immediately after diagnosis, followed by continuous i.v.-infusion of 2 µg/kg per minute until either hospital discharge or initiation of coronary artery bypass grafting, or for up to 72 hours. At least 4 hours before discharge all local or systemic bleedings should have been controlled and terminated.
Patients weighing >120 kg should receive a maximum bolus of 22.6 mg followed by a maximum infusion rate of 15 mg/h. Patients with renal impairment evidenced by CrCl <50 ml/min should receive the standard 180 µg/kg loading dose followed by infusion at 1 µg/kg/min.

Study results

Eptifibatide was licensed due to the positive results of the so-called PURSUIT study encompassing 10,948 patients. In this study all patients had suffered either unstable angina or a non-ST-segment-elevation myocardial infarction. Significantly fewer patients developed a myocardial infarction under therapy with eptifibatide. Death rates showed a tendency in favor of eptifibatide, but this superiority was not statistically significant.

Additional information

Sometimes the treating physicians require the patient after discharge from hospital to continue treatment with aspirin or clopidogrel for a few weeks, some months or even for life to prevent recurrence of symptoms, development of myocardial infarction and/or death related to cardiovascular disease. This advice should be strictly followed.
Eptifibatide is one of very many antiplatelet drugs that all have different consequences on the platelet's activity.

Inventors

Eptifibatide was discovered by a team led by Robert M. Scarborough and David Phillips, at COR Therapeutics which was acquired by Millennium Pharmaceuticals in 2001.