A Phase I Study to Evaluate the Safety, Tolerability, and Pharmacokinetics of BAL2420 in Healthy Adult Subjects

Inclusion Criteria: * Body mass index: 18.0 to 30.0 kg/m2, inclusive, at screening * Total body weight: \> 50 kg at screening Exclusion Criteria: * Any uncontrolled or active major systemic disease, * Active infection * Acute illness within 5 days prior to the first study drug administration that, in the opinion of the Investigator, may impact safety assessments. * Clinically-significant physical examination, vital signs, laboratory safety tests, or ECG abnormalities * History of risk factors for QT prolongation or Torsades de Pointes * QTcF (Fridericia's corrected QT interval) \> 450 msec (males) and \> 470 msec (females) at screening. * Receipt of prescribed medication other than hormonal contraceptives within the 30 days prior to admission to the clinical site. * Receipt of over-the-counter medication, vitamin preparations and other food supplements, or herbal medications (e.g., St. John's wort) within 14 days prior to admission to the clinical site. * History of relevant drug and/or food allergies, particularly to antibiotics. * History of tobacco use or e-cigarette within the past 6 months prior to the first study drug administration. * History of alcohol abuse or drug addiction (including soft drugs like cannabis products) within 12 months prior to screening. * Average intake of more than 24 units of alcohol per week: one unit of alcohol equals approximately 250 mL of beer, 100 mL of wine, or 35 mL of spirits. * Positive screen for hepatitis B surface antigen, hepatitis B core antibodies, hepatitis C virus antibodies, human immunodeficiency virus 1 and 2 antibodies, or syphilis at screening. Note: Hepatitis B vaccination is allowed.