Achieving optimal beta1-blockade with metoprolol CR/Zok.

The metoprolol CR/Zok is a multi-unit formulation containing metoprolol succinate controlled release (CR/Zok) in the form of individual drug delivery units (microcapsules). Each microcapsule acts as a diffusion cell and is designed to deliver metoprolol succinate at a near constant rate for about 20 hours independently of food intake, pH and other physiological variations. Taking the half-life of metoprolol into account this yields an even plasma concentration over 24 hours with a once daily dosage scheme. The formulation allows for once daily dosing, avoiding peaks and troughs in the plasma concentration of the drug. This leads to an even beta1-blockade over 24 hours in dose ranges from 12.5 mg to 200 mg once daily. Plasma fluctuations are considerably decreased compared with immediate release formulations and cardioselectivity is well maintained also on 200 mg CR/Zok. Vital important beta1-blockade is maintained for 24 hours. Metoprolol CR/Zok is well tolerated and well-being has been shown to be improved with metoprolol CR/Zok in patients with chronic heart failure as illustrated in the findings from the MERIT-HF study.