Pharmacokinetic Study of Letrozole Polymorphs in Rats / 医药导报

ABSTRACT

Objective To study the gastrointestinal absorption process of three letrozole polymorphs in rats, and evaluate the different pharmacokinetics parameters of different polymorphs. Methods A total of 18 SD rats were given the different letrozole polymorphs. Then the high-performance liquid chromatographic method was used for the determination of plasma concentration of letrozole in these SD rats.Finally the pharmacokinetic parameters among the different polymorphs were calculated. Results Cmax of letrozole crystal form I, crystal form II and crystal form III were (9.247± 4.612) ,(23.387± 9.049) and (15.682±1.589) mg·L-1, respectively, and AUC0→t were(198.115±47.014) ,(476.641±125.467) and (271.817±41.068) mg·L-1·h,respectively. Conclusion The different crystal forms of letrozole result in different plasma concentration in SD rats. Crystal form II may be its preponderant polymorphs which deserves further research and development.