Inclusion Criteria:  Male or female subjects, age 8 to < 18 (inclusive) who have written and signed parental/legal authorized representative (LAR) informed consent and pediatric assent. Currently hospitalized with a suspected or confirmed bacterial infection and receiving or planned to receive systemic antibiotic therapy other than omadacycline. Weight within the 5th and 95th percentile for age and sex. Subjects must not be pregnant or nursing at the time of enrollment, and must agree to use a highly effective birth control method during the study  Exclusion Criteria:  Evidence of a medical condition that may pose a safety risk or impair study participation. Confirmed or suspected SARS-CoV-2 infection. Has a history of hypersensitivity or allergic reaction to any tetracycline antibiotic. Has received an investigational drug within the past 30 days.