TABLE 2.

Population-median parameter estimates of PD model

ParameteraEstimateSD
Clearance rate (liters/h)99.4182.426
Volume of central compartment (liters)430.8880.858
KgmaxS [log10 (CFU/ml)/h (10−3)]9.7560.508
C50gS (mg/liter)1.9320.585
HgS0.3610.120
KgmaxR [log10 (CFU/ml)/h (10−3)]6.1951.657
C50gR (mg/liter)2.0191.575
HgR4.5424.508
KkmaxS [log10 (CFU/ml)/h]15.8290.763
C50kS (mg/liter)7.6520.146
HkS1.3880.965
KkmaxR [log10 (CFU/ml)/h]29.3790.184
C50kR (mg/liter)22.4050.233
HkR (10−1)45.3260.009
POPMAX (CFU/ml)2.023 × 1097.102 × 108
Total population (NS + NR) (CFU/ml)1.027 × 1062.018 × 104
Resistant population (NR) (CFU/ml [10−1])13.120.004
  • a Kgmax, rate constant for maximum bacterial growth; Kkmax, rate constant for maximal bacterial kill; C50k, the drug concentration needed to achieve a 50% maximal killing rate; C50g, the drug concentration needed to achieve a 50% effect on the maximum growth rate; Hk, sigmoidicity constant for microbial killing; Hg, sigmoidicity constant for drug effect on microbial growth; N, number of bacilli. The parameters are provided for the sensitive (S) and resistant (R) subpopulations. POPMAX, estimated maximal size of the bacterial density in control HFSs after bacterial growth enters stationary phase.