This will be a Phase 1, randomized, double-blind, single-center, placebo-controlled study in healthy male and female adult subjects. Subjects will be randomly assigned to receive either nafithromycin or placebo by intravenous (IV) infusion based on a double-blind randomization schedule. The following treatments will be administered:

• Nafithromycin 200 mg or placebo administered as IV infusions twice daily (q12h) over a period of 3 hours for 3 days.
• Eight subjects (n=8) will receive nafithromycin and 2 subjects (n=2) will receive placebo.

Inclusion Criteria:

• Body mass index (BMI) ≥18 to ≤32 kg/m2, both inclusive.
• Stable health based on a medical history without any major pathology/surgery in the 6 months before Screening and no clinically significant physical examination findings or clinical laboratory test results
• Resting supine blood pressure of 90 to 139 mmHg (systolic) and 60 to 89 mmHg (diastolic) and a resting heart rate of 50 to 100 beats per minute at Screening and Check-in (Day -1).
• Calculated creatinine clearance ≥80 mL/min (Cockroft-Gault method) at Screening.
• Computerized 12-lead electrocardiogram (ECG) recording without signs of clinically significant pathology and showing no clinically significant deviation as judged by the investigator

Exclusion Criteria:

• Participation in another investigational drug or device study or treated with an investigational product within 30 days or 5 half-lives, whichever is longer, before study drug administration in this study.
• History/evidence of clinically relevant pathology
• History of clinically significant food or drug allergy
• Positive alcohol or urine drug screen