After a run-in period on placebo, 26 patients with
essential hypertension were prescribed single-blind
tibalosine, 150 mg daily. On
tibalosine their blood pressure decreased from 157/101 to 147/93 mm Hg (p less than 0.001) and their heart rate from 74 to 68 beats per minute (p less than 0.01), while plasma
renin activity tended to fall from 0.81 to 0.65 ng/ml/hr (p = 0.06). Twelve patients, maintained on monotherapy with
tibalosine for an average of 3.8 months, kept a diastolic pressure below 90 mm Hg. Ten patients, whose diastolic pressure on
tibalosine alone remained equal to or higher than 90 mm Hg were continued on this
drug for 6.6 months, but were additionally given in a double-blind and randomized way either placebo, or
atenolol 100 mg, or
chlorthalidone, 50 mg, daily. As compared to
tibalosine plus placebo, blood pressure and heart rate decreased further on
tibalosine plus
atenolol from 148/97 to 140/90 mm Hg (p less than 0.05) and from 70 to 60 beats per minute (p less than 0.05), respectively. The additional blood pressure lowering effect of
tibalosine plus
chlorthalidone to a level of 143/96 mm Hg was not statistically significant. Eight of 10 patients' blood pressure responded better to
tibalosine combined with
atenolol than with
chlorthalidone. Because of adverse reactions
tibalosine was discontinued in 8 of the 26 patients (31%), namely in 4 who prematurely dropped out from the study and in another 4 patients, who remained adherent to the protocol.
Somnolence, weary legs and dry mouth were reported more frequently (p less than 0.05) on
tibalosine than on placebo.
IN CONCLUSION: