Chengdu Hengrui Pharmaceutical Co. Ltd.

Main study objectives To study the pharmacokinetics of the test preparation sildenafil citrate tablets (specification: 50mg, produced by Chengdu Hengrui Pharmaceutical Co., Ltd.) and the reference preparation sildenafil citrate tablets (Viagra®, specification: 50mg, produced by Pfizer Pharmaceutical Co., Ltd.) in healthy adult participants in the fasting and fed state, and to evaluate the bioequivalence of the two preparations in the fasting and fed state Secondary study objectives To evaluate the safety of the test preparation sildenafil citrate tablets and the reference preparation sildenafil citrate tablets (Viagra®) in the fasting and fed state in healthy Chinese participants.

Primary objective: To investigate the in vivo pharmacokinetic characteristics of pregabalin capsules produced by Chengdu Hengrui Pharmaceutical Co., Ltd. and pregabalin capsules produced by Pfizer Manufacturing Deutschland GmbH, Betriebsstatte Freiburg (licensed by Upjohn EESV) in healthy Chinese subjects after a single oral dose under fasting/postprandial conditions, and to evaluate the bioequivalence of the two preparations. Secondary objective: To evaluate the safety of the test and reference preparations of pregabalin capsules after a single oral dose in healthy Chinese subjects.

Primary objective: To investigate the similarity between the single-dose oral administration of metformin glibenclamide tablets (I) (specification: 500mg/2.5mg) produced by Chengdu Hengrui Pharmaceutical Co., Ltd. and the metformin glibenclamide tablets (I) (specification: 500mg/2.5mg) of the licensed manufacturer Merck SANTE S.A.S. under fasting/postprandial conditions in healthy Chinese subjects through a fasting/postprandial pilot study, to investigate the in vivo pharmacokinetic characteristics and intra-individual coefficient of variation of the drug, to provide a decision basis for whether to enter the formal trial, and to verify the rationality of the formal trial sample size, blood collection points and trial cycle interval settings. Secondary objective: To evaluate the safety of the test and reference preparations of single-dose oral metformin glibenclamide tablets (I) (specification: 500mg/2.5mg) in healthy Chinese subjects.