ABSTRACT
Objective To study the characteristics of pharmacokinetics and pharmacodynamics of insulin dry powder inhalation and its relative bioavailability as compared with subcutaneous injection of regular insulin. Methods In this open,single-center,randomized,two-period,cross-over,euglycemic glucose clamp study,18 healthy volunteers(14 men and 4 women),aged(24.9?1.7)years,with body mass index(20.6?1.2)kg/m~2, received the insulin dry powder inhalatin(80 U)or regular insulin(15 U)subcutaneous administration.The blood samples of this study at 0,20,30,40,50,60,70,80,90,100,110,120,135,150,165,180,195, 210,225,240,270,300,330,360,390,420,450 and 480 rain were taken for serum insulin measurement, meanwhile,glucose infusion rates(GIR)were determined per 5 minutes over a period of 8 hours.Results The C_(max)were(57.9?17.8 vs 114.5?29.7)mU/L(tested vs reference preparation),T_(max)were(46.7?45.6 vs 107.8?33.7)min,GIR_(max)were(3.35?0.98 vs 5.17?1.75)mg?kg~(-1)?min~(-1)and T_(GIRmax)were(88.3?17.0 vs 151.9?34.6)min.The relative bioavailability was(10.26?2.25)%,and the relative bioefficacy was(14.33?7.26)%.Conclusion The study shows that insulin dry powder inhalation is absorbed via lungs and its action sets in earlier than that of the regular insulin injected subcutaneously.These pharmacokinetie and pharmacodynamic data may provide a reliabe guide for further clinical trial.