title: Optimization of dose and dose regimen of biapenem based on pharmacokinetic and pharmacodynamic analysis.
abstract: Pharmacokinetic and pharmacodynamic (PK/PD) parameters, which are important indices of the therapeutic efficacy of antimicrobials, and the minimum inhibitory concentration (MIC) predictive of clinical efficacy at common clinical doses, were examined for biapenem (BIPM; 300 mg b.i.d.), imipenem/cilastatin (IPM/CS; 500 mg/500 mg b.i.d.), meropenem (MEPM; 500 mg b.i.d.), and ceftazidime (CAZ; 1000 mg b.i.d.), using a mouse model of thigh infection caused by Pseudomonas aeruginosa. The PK/PD parameter that most closely correlated with the therapeutic efficacy of all these antimicrobials was time above MIC (T > MIC). The values of T > MIC predictive of clinical efficacy against P. aeruginosa infection varied among antimicrobials and were >/=17%, >/=17%, >/=23%, and >/=33% for BIPM, IPM/CS, MEPM, and CAZ, respectively. From these values and the known plasma concentrations of the antimicrobials in humans after administration at the common clinical doses, the MIC for bacterial strains at which clinical efficacy can be expected was estimated to be </=4.4 microg/ml for BIPM, </=6.1 microg/ml for IPM/CS, </=2.2 microg/ml for MEPM, and </=13.6 microg/ml for CAZ. These MICs nearly coincided with the MIC(80) of the antimicrobials for 104 clinical isolates of P. aeruginosa strains. These results indicate that, even at a low dose, of 300 mg b.i.d., the clinical efficacy of BIPM against P. aeruginosa infection can be expected to be comparable to that of IPM/CS, MEPM, and CAZ.
authors.affiliation: Pharmaceutical Research Center, Meiji Seika Kaisha, Ltd., 760 Morooka-cho, Kohoku-ku, Yokohama 222-8567, Japan. toshihiko_takata@meiji.co.jp
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Takata
authors.forename: Kazumasa
authors.initials: K
authors.lastname: Aizawa
authors.forename: Atsuyuki
authors.initials: A
authors.lastname: Shimizu
authors.forename: Shiro
authors.initials: S
authors.lastname: Sakakibara
authors.forename: Hiroomi
authors.initials: H
authors.lastname: Watabe
authors.forename: Kyoichi
authors.initials: K
authors.lastname: Totsuka
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000493:pharmacokinetics / Q000627:therapeutic use; D002442:Ceftazidime / Q000008:administration & dosage / Q000493:pharmacokinetics / Q000627:therapeutic use; D004334:Drug Administration Schedule; D006801:Humans; D015378:Imipenem / Q000008:administration & dosage / Q000493:pharmacokinetics / Q000627:therapeutic use; D008297:Male; D000077731:Meropenem; D051379:Mice; D008813:Mice, Inbred ICR; D008826:Microbial Sensitivity Tests / Q000592:standards; D011552:Pseudomonas Infections / Q000188:drug therapy* / Q000382:microbiology; D011550:Pseudomonas aeruginosa / Q000187:drug effects*; D013845:Thienamycins / Q000008:administration & dosage / Q000493:pharmacokinetics / Q000627:therapeutic use; D013848:Thigh / Q000382:microbiology
chemical_list: D000900:Anti-Bacterial Agents; D013845:Thienamycins; D015378:Imipenem; D002442:Ceftazidime; D000077731:Meropenem; C065257:biapenem