BREVIBLOC

What it is

Brevibloc is esmolol hydrochloride supplied as a 100 mg/10 mL vial injection. It is also supplied as a powder for injection in a 50 mL vial containing 2.5 g esmolol hydrochloride. The 100 mg/10 mL vial is a clear, colourless to light yellow, sterile, nonpyrogenic solution for intravenous infusion. Brevibloc is a beta 1-selective (cardioselective) adrenergic blocking agent with rapid onset and a short duration of action, with an elimination half-life of approximately 9 minutes.

Approved indications

— Rapid control of ventricular rate in patients with atrial fibrillation or atrial flutter in perioperative, postoperative, or other emergent circumstances where short term control of ventricular rate with a short-acting agent is desirable. — Non-compensatory sinus tachycardia where, in the physician's judgement, the rapid heart rate requires specific intervention.

Dosing overview

In the treatment of supraventricular tachycardia, responses to Brevibloc usually occur within the range of 50 to 200 micrograms/kg/min, with an average effective dosage of approximately 100 micrograms/kg/min, although dosages as low as 25 micrograms/kg/min have been adequate in some patients. To initiate treatment of a patient with supraventricular tachycardia, administer a loading infusion of 500 micrograms/kg/min over one minute followed by a 4 minute maintenance infusion of 50 micrograms/kg/min. Maintenance dosages above 200 micrograms/kg/min have not been shown to have significantly increased benefits and are not recommended. Brevibloc is not intended for use in chronic settings or for treatment periods greater than 24 hours duration.

Key safety warnings

In clinical trials, 20–50% of patients treated with Brevibloc have had hypotension, generally defined as systolic pressure less than 90 mmHg and/or diastolic pressure less than 50 mmHg, with about 12% of patients being symptomatic. Hypotension can occur at any dose but is dose-related. Decrease of dose or termination of infusion reverses hypotension, usually within 30 minutes. Sympathetic stimulation is necessary in supporting circulatory function in congestive heart failure and beta-blockade carries the potential hazard of further depressing myocardial contractility and precipitating more severe failure. At the first sign or symptom of impending cardiac failure Brevibloc should be withdrawn. Several cases of death have been reported in complex clinical states where Brevibloc was presumably being used to control ventricular rate. Patients with bronchospastic diseases should, in general, not receive beta-blockers. Because of its relative beta 1-selectivity and titratability, Brevibloc may be used with caution in patients with bronchospastic diseases, but since beta 1-selectivity is not absolute, Brevibloc should be carefully titrated to obtain the lowest possible effective dose. Infusion concentrations of 20 mg/mL were associated with more venous irritation, including thrombophlebitis, than concentrations of 10 mg/mL. Concentrations greater than 10 mg/mL or infusion into small veins or through a butterfly catheter should be avoided.

Contraindications

Patients with hypersensitivity to esmolol hydrochloride or any of the excipients should not be given Brevibloc. Brevibloc is contraindicated in patients with sinus bradycardia, heart block greater than first degree, cardiogenic shock or overt heart failure. Brevibloc is also contraindicated in patients with severe bradycardia (less than 50 beats per minute), sick sinus syndrome, severe AV-nodal conductance disorders (without pacemaker), second and third degree AV-block, severe hypotension, non-treated phaeochromocytoma, pulmonary hypertension, acute asthma attack and metabolic acidosis. Brevibloc should NOT be administered concomitantly with IV verapamil or within close proximity since fatal cardiac arrest has occurred in patients receiving both drugs.

Regulatory history

Brevibloc esmolol hydrochloride 100 mg/10 mL injection vial (ARTG 43494) was first listed on 4 March 1993. Brevibloc esmolol hydrochloride 2.5 g powder for injection for infusion vial (ARTG 310943) was first listed on 21 January 2020.