Abstract: Objective To research and evaluate the efficacy of cefazolin sodium based on physiological pharmacokinetic models. Methods Physiologically based pharmacokinetic (PBPK) model of cefazolin was established using software and then further validated with the data collected from literatures. Plasma concentration-time curves in corresponding tissues and organs were calculated. Treatment efficacy was evaluated based on the plasma concentration-time curves in relevant organs with specific parameters. Those factors which have influence on the efficacy were also discussed meanwhile. Results For the single intravenous administration of cefazolin by 0.5, 1.0 and 4.0 g. The determining factor (r² values) of the results of model established and actual measurement with literature data were 0.863 0.933 and 0.905. The rates of model established and actual measurement of the corresponding average value of the area under the curve (AUC_0-t) were 101.1% 108.3% and 105.3%. Further calculation shown the effectiveness of lung, heart, kidney, skin and reproductive system with minimum inhibitory concentration of streptococcus pneumoniae, streptococcus haemolyticus, staphylococcus aureus, escherichia coli and roteus mirabilis were 18.7%~99.7%. Conclusion The PBPK model of cefazolin preparations can be described the pharmacokinetic of drugs in human, it is suitable for the efficacy evaluation of anti-infective drugs. Combined with the susceptibility test of antibiotics results, to achieve the better effectiveness by adjust the plan according to the treatment purpose.

Key words: cefazolin sodium, PBPK, efficacy, pharmacodynamic