Studies on pharmacokinetics of two long-acting triptorelin injections in Beagle dogs

Objective To study pharmacokinetics of two long-acting triptorelin injections(Decapeptyl 3.75 mg and Diphereline 3.75 mg) in male Beagle dogs.Methods A tatal of 10 healthy male Beagle dogs were randomly divided into two groups.The plasma concentration of triptorelin was determained by a validated LC-MS/MS method after intramuscular injection of the two injections.The pharmacokinetic parameters were calculated by DAS 3.2.2.Results The mean pharmacokinetic parameters were as follows: Cmax(11.95±2.127) and(27.93±8.752) ng/mL,Tmax(1.2±0.4) and(0.7 ±0.3) h,T1/2(244.7±99.25) and(239.6±87.50) h,AUC(0-t)(758.8±111.9) and(492.3±125.9)ng h mL-1,AUC(0-)(778.9± 101.3)and(515.6±125.3) ng h mL-1,respectively for Decapeptyl and Diphereline.Conclusion The Cmax、AUC(0-) and AUC(0-t)of Diphereline and Decapeptyl in Beagle dogs were different significantly.These two injections could keep the plasma concentration above the LLOQ for more than 28 days.