• To assess the safety and tolerability of single and multiple ascending intravenous doses of AAI101 (SAD & MAD) in healthy male subjects.
• To assess the safety and tolerability of single and multiple ascending intravenous doses of AAI101 in combination with fixed intravenous doses of piperacillin or cefepime in healthy male subjects

Inclusion Criteria:

• Male healthy volunteers aged between 18 and 45 years (inclusive) at screening.
• Body mass index (BMI) of 18.0 to 30.0 Kg/m2 (inclusive) at screening.
• Healthy as determined by the investigator on the basis of medical history, physical examination findings, clinical laboratory test results, vital sign measurements, and digital 12 lead ECG readings (all results were to be within normal range or considered non-clinically significant by the investigator).
• Non-smoker or smoker of fewer than 10 cigarettes per day as determined by medical history. Had to be able to abstain from smoking during the inpatient stay.
• Ability to communicate well with the investigator in the local language, and to understand and comply with the requirements of the study.

Main Exclusion Criteria:

• Any significant cardiovascular (e.g., hypertension), hepatic, renal, respiratory (e.g., childhood asthma), gastrointestinal, endocrine (e.g., diabetes, dyslipidemia), immunologic, hematological, neurologic, or psychiatric disease.
• Acute disease state (e.g., nausea, vomiting, fever, diarrhea) within 7 days before study Day 1.

Healthy male subjects