Ro 3-4787, a new β-adrenoceptor blocking agent: Studies in normal volunteers.

1 A new β-adrenoceptor blocking agent, Ro 3-4787, was administered orally to resting subjects. Peak levels of 106.2 ± 15.5 ng/ml were reached after 20 mg given in the fasting state. After intravenous administration, an inverse rectilinear relationship was shown between the log dose (2 mg-20 mg) and the heart rate during vigorous exercise on a bicycle ergometer. 2 A double-blind study in five normal subjects using 0.03 mg/kg and 0.15 mg/kg showed that propranolol and Ro 3-4787 were equally effective in reducing the exercise heart rate. There was an inverse correlation between the log plasma level before exercise and the heart rate during exercise for both drugs over the range studied.