This is a randomized, active-controlled, multicenter phase II clinical trial. The study aims to evaluate the efficacy, safety and tolerability of two different dosing regimens of ASK0912 for Injection compared with Polymyxin B Sulfate for Injection in adult patients with hospital-acquired bacterial pneumonia (HABP) or ventilator-associated bacterial pneumonia (VABP) caused by multidrug-resistant or carbapenem-resistant Gram-negative bacilli. Eligible subjects will be randomly assigned to one of three treatment groups: ASK0912 Regimen 1, ASK0912 Regimen 2, or Polymyxin B Sulfate active comparator group. Subjects will receive assigned intravenous study treatment for 7 to 14 days. The primary efficacy endpoints include clinical cure rate at the Test of Cure (TOC) visit and Day 28 all-cause mortality in the modified intent-to-treat (MITT) population. Safety assessments will be conducted throughout the study to monitor adverse events, laboratory parameters and other safety indicators.
1. Aged 18-75 years on the day of informed consent signature;
2. Require intravenous antibiotic therapy for hospital-acquired bacterial pneumonia (HABP)/ventilator-associated bacterial pneumonia (VABP).
3. At least one clinical sign or symptom of HABP/VABP.
4. At least one laboratory abnormality of HABP/VABP.
1. Subjects with known allergy to polymyxins or carbapenems, regardless of the severity of the reaction; or subjects with a severe hypersensitivity reaction to any other β-lactam agent.
2. Subjects who have received any investigational product within 3 months prior to enrollment, or subjects who have previously participated in this clinical study.
3. Has a baseline lower respiratory tract specimen Gram stain that shows the presence of Gram-positive cocci only.
4. Known or suspected pneumonia caused by Mycoplasma, Chlamydia, Legionella, fungi, parasites, viruses, or chemical etiologies (including gastric aspiration, inhalation injury).Additionally, subjects with confirmed or suspected community-acquired bacterial pneumonia (CABP) are excluded.