In vitro activity: Tebipenem Pivoxil has high intestinal apical membrane permeability due to plural intestinal transport routes, including the uptake transporters such as OATP1A2 and OATP2B1 as well as simple diffusion. Tebipenem Pivoxil is quickly converted to tebipenem (TBPM), an active form of Tebipenem Pivoxil. Tebipenem Pivoxil are absorbed quickly, and the bioavailability is 71.4%, 59.1%, 34.8% and 44.9%, respectively, in mouse, rat, dog and monkey. Tebipenem shows the strongest bactericidal activity as early as 2 h after exposure at two times the MIC. Tebipenem shows higher affinities for PBP 1A and PBP 2B, high-molecular-weight enzymes, and for PBP 3, a low-molecular-weight enzyme, than for PBP 2X. Tebipenem has a potent activity against Neisseria gonorrhoeae; its activity is comparable to it of cefixime that has most potent activity among oral antibiotics.

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