Objective:To study the effect of Wuzhi capsules on tacrolimus trough concentration in kidney transplant recipients with different CYP3A5 genotypes.Methods:From June 2015 to October 2019, 162 patients who underwent renal transplantation for the first time were retrospectively analyzed. The patients were divided into two groups, combined and uncombined, according to whether combined with Wuzhi capsules. There were 81 cases in the uncombined group (55 males and 26 females), and 81 in the combined group (62 males and 19 females). There was no significant difference between the two groups( P=0.219). The ages of the uncombined group and the combined group were (39.26±11.91) years old and (37.21±10.88) years old ( P=0.103), the weights were (62.39±11.64) kg and (66.18±13.89)kg ( P=0.298), systolic blood pressure were (147.28±20.24) mmHg and (145.00±16.42) mmHg (1 mmHg=0.133 kPa)( P=0.276), diastolic blood pressure were (92.25±13.87) mmHg and (92.20±12.53) mmHg ( P=0.886), alanine aminotransferase were (12.24±8.59) U/L and (17.06±13.11) U/L ( P=0.015), aspartate aminotransferase were (17.76±9.12) U/L and (16.57±8.37) U/L ( P=0.463), fasting blood glucose were (8.70±3.48) mmol/L and (7.18±2.74)mmol/L ( P=0.006), hemoglobin were (98.96±17.53) g/L and (101.05±18.67) g/L ( P=0.789), creatinine were (665.22±296.55) μmol/L and (797.32±279.32) μmol/L ( P=0.007), estimated glomerular filtration rate were (11.47±14.11) ml/(min·1.73m 2) and (8.85±3.71) ml/(min·1.73m 2) ( P=0.130)in the kidney transplant recipients before surgery. Among the 162 cases in this study, there were 86 cases (53.09%) of CYP3A5*1*3 genotype, 17 cases (10.49%) of CYP3A5*1*1 genotype, 59 cases (36.42%) of CYP3A5*3*3 genotype, and the minimum allele frequency of CYP3A5*1 was 37.04%. In the uncombined group, CYP3A5*1*3 genotype 39 cases (48.15%), CYP3A5*1*1 genotype 5 cases (6.17%), and CYP3A5*3*3 genotype 37 cases (45.68%). In the combined group, CYP3A5*1*3 genotype 47 cases (58.02%), CYP3A5*1*1 genotype 12 cases (14.81%), and CYP3A5*3*3 genotype 22 cases (27.16%), with statistically significant differences in the two groups ( P=0.024). The patients were treated with a triple immunosuppressive regimen (tacrolimus+ mycophenolate mofetil+ glucocorticoid) based on tacrolimus [initial dose: 0.15-0.30 mg/(kg·d)], combination of Wuzhi capsules in the combination group (11.25 mg, twice a day). The trough concentration of tacrolimus was detected by enzyme-linked immunosorbent assay, compare the difference in the trough concentration of tacrolimus between the two groups. The relationship between the effect of Wuzhi capsules and CYP3A5 gene polymorphism was compared, and compare the changes before and after the application of CYP3A5 genotype combined with Wuzhi Capsules. The influencing factors of tacrolimus trough concentration were analyzed by multiple linear regression. Results:In the combined with Wuzhi capsules, the dose corrected trough concentration (C 0/D) of tacrolimus was higher than that in patients without Wuzhi capsules, and the extent of increase was related to genotype. The C 0/D of tacrolimus in patients with CYP3A5*3*3 genotype in the combination and non-combination groups were (12.15±2.95) (ng·ml -1/0.1mg·kg -1·d -1) and (9.99±2.33) (ng·ml -1/0.1mg·kg -1·d -1) ( P=0.004), CYP3A5*1*3 genotype were (11.11±3.20) (ng·ml -1/0.1mg·kg -1·d -1) and (6.86±1.62) (ng·ml -1/0.1mg·kg -1·d -1) ( P<0.001), and there were significant difference. However, CYP3A5*1*1 genotype were(8.29±2.64) (ng·ml -1/0.1mg·kg -1·d -1) and (6.16±2.87) (ng·ml -1/0.1mg·kg -1·d -1) ( P=0.160), there was no significant difference. The tacrolimus C 0/D of the combined group before and after the Wuzhi capsule were as follows: CYP3A5*3*3 genotype: (7.18±2.33)(ng·ml -1/0.1mg·kg -1·d -1) and (13.33±3.09) (ng·ml -1/0.1mg·kg -1·d -1) ( P<0.001); CYP3A5*1*3 genotype: (5.14±2.14) (ng·ml -1/0.1mg·kg -1·d -1) and (10.61±3.20) (ng·ml -1/0.1mg·kg -1·d -1) ( P<0.001); CYP3A5*1*1 genotype: (5.17±3.75) (ng·ml -1/0.1mg·kg -1·d -1) and (8.31±2.74) (ng·ml -1/0.1mg·kg -1·d -1)( P=0.002), and the differences were statistically significant. The results of multiple linear regression showed that the combination of Wuzhi capsules (β=0.508, P<0.001) and CYP3A5 genotype(CYP3A5*1*3 and CYP3A5*3*3: β=-0.361, P<0.001; CYP3A5*1*1 and CYP3A5*3*3: β=-0.425, P<0.001)could influence the trough concentration. The sex (β=-0.100, P=0.124) and age (β=-0.003, P=0.967) of renal transplant recipients had no statistical significance to tacrolimus C 0/D. Conclusions:In the renal transplant patients, CYP3A5 genotype and combined use of Wuzhi capsules are the main factors affecting tacrolimus C 0/D. In order to achieve the expected trough concentration as soon as possible, the interaction between CYP3A5 genotypes and drug combination should be considered.