Comparative potencies and beta2‐adrenoreceptor selectivities of rimiterol and salbutamol aerosols.

Abstract

Rimiterol hydrobromide, a ,B-adrenoceptor stimulating drug, is a member of a new series of sympathomimetic amines cycized about the a-carbon atom. Studies in man have demonstrated rimiterol to be an effective short-acting bronchodilator by the inhalational and parenteral routes of administration, with a high degree of 12 -adrenoceptor selectivity (Griffin & Turner, 1971; Prime, Kamburoff & Gunthner, 1971; Phillips, Woolnough, Marinova & Turner, 1972; Svedmyr, Malmberg & Thiringer, 1972;Griffin, Williams & Maughan, 1973; Shenfield & Paterson, 1973;Cooke, Kerr, Willey, Hoare, Grant & Crompton, 1974;Evans, Shenfield, Thomas, Walker & Paterson, 1974;Bianco, Kamburoff & Prime, 1975; Marlin & Turner, 1975a, b & c Figure 1. The % FEV1 increases from control after all the doses of the drugs were significantly greater than those after placebo (P < 0.01). There was no significant difference between the ventilatory responses after 1, 2 and 4 inhalations of each drug. However, the % FEV1 increases after 8 and 16 inhalations of salbutamol were significantly greater than those after rimiterol (P < 0,05). The mean, peak heart rate changes from control after the cumulative doses of all the treatments are shown in Table 1

A Brief Review of Sympathomimetic Bronchodilators and a Description of a New Selective Agent, Rimiterol Hydrobromide

“…Bianco et al [32] confirmed this potency ratio when they obtained peak bronchodilator effects from 500 ,«g rimiterol compared with 200 ,«g salbutamol by aero sol in asthmatic patients. More recently, sal butamol has been reported to be three and a half times more potent by weight than rimi terol [33]. Other investigators, however, have reported rimiterol to be equally potent as a bronchodilator with isoprénaline [8,29], and with salbutamol [30], Harris [34] found no statistically signifi cant difference in bronchodilating effect when equal doses of rimiterol and terbutaline were compared in asthmatic patients.…”