Immediate and modified release oral dosage forms of tebipenem pivoxil including dosage form cores are provided. The dosage form core includes tebipenem pivoxil in free base or salt form, and excipients including a binder, a lubricant, optionally a diluent, and optional additional excipients. The weight to weight ratio of tebipenem pivoxil to the excipients in the dosage form core is from 30:60 to 60:30. The disclosure includes methods of treating bacterial infections including complicated urinary tract infections.