An observational study in Carbapenem-Resistant Acinetobacter Baumannii Infection, sponsored by Central South University. Not yet recruiting. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-10-29.
Sponsored by Central South University · Observational
The goal of this prospective, multicenter observational study is to learn which antibiotic treatment strategies are associated with better outcomes in critically ill adults with severe infections caused by carbapenem-resistant Acinetobacter baumannii (CRAB). The study will also evaluate the safety and costs of different treatments and develop prediction models to support personalized treatment decisions.
The main questions it aims to answer are:
Are there differences in 28-day survival between patients receiving polymyxin-based and non-polymyxin-based antibiotic treatments?
Which treatment strategies are associated with better clinical recovery, bacterial clearance, and fewer adverse events, particularly acute kidney injury?
Can clinical data and machine learning help predict treatment outcomes and support safer, more effective treatment decisions?
Researchers will compare patients receiving polymyxin-based combination therapy with those receiving non-polymyxin-based treatments, including high-dose sulbactam-based, tigecycline-based, and newer antibiotic regimens. Treatment decisions will be made by the patients' treating physicians as part of routine clinical care, rather than assigned by the researchers.
Participants will:
Receive antibiotic treatments determined by their treating physicians.
Have clinical information collected during hospitalization, including laboratory tests, bacterial cultures, organ function, antibiotic use, adverse events, and medical costs.
Be followed for 28 days after starting targeted antibiotic treatment to assess survival and clinical outcomes.
Be contacted by telephone if necessary to confirm their health status after hospital discharge.
Central South University is the lead sponsor of 133 studies on the registry; 31 are open to participants now.
Counted across the registry records on this site, refreshed daily.
The study population consists of adult patients aged 18 years or older admitted to intensive care units at participating hospitals with severe infections caused by carbapenem-resistant Acinetobacter baumannii (CRAB). Eligible infections include lower respiratory tract, bloodstream, and intra-abdominal infections. CRAB must be identified as the primary pathogen or a definite co-pathogen. Patients will be consecutively screened and classified according to their initial antibiotic treatment strategy, including polymyxin-based, sulbactam-based, tetracycline-based, and newer antibiotic regimens. Treatment decisions will be made by the attending physicians as part of routine clinical care.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Participants whose initial anti-CRAB treatment strategy on Day 0 includes intravenous polymyxin B, colistin sulfate, or colistimethate sodium as a core antibiotic. Participants receiving polymyxins in combination with other anti-CRAB antibiotics will remain in Cohort A.
Drug: Antibiotic Therapy for CRAB Infection
Participants whose initial treatment strategy on Day 0 includes sulbactam alone or a sulbactam-containing combination, without polymyxins, sulbactam-durlobactam, or cefiderocol.
Drug: Antibiotic Therapy for CRAB Infection
Participants whose initial treatment strategy on Day 0 includes tigecycline, eravacycline, or another tetracycline-class antibiotic, without polymyxins, sulbactam-based treatment, sulbactam-durlobactam, or cefiderocol.
Drug: Antibiotic Therapy for CRAB Infection
Participants whose initial treatment strategy on Day 0 includes sulbactam-durlobactam or cefiderocol without polymyxins. A nested exploratory cohort (B3b) will include eligible participants initially assigned to Cohort A, B1, or B2 who subsequently initiate sulbactam-durlobactam or cefiderocol after microbiological confirmation and no later than Day 14. These participants will retain their original Day 0 cohort assignment. A separate time origin (Tnew) will be defined for the nested analysis.
Drug: Antibiotic Therapy for CRAB Infection
Participants will receive antibiotic treatment for carbapenem-resistant Acinetobacter baumannii (CRAB) infection as part of routine clinical care. Treatment strategies may include polymyxin-based, sulbactam-based, tetracycline-based, or newer antibiotic regimens. The selection of antibiotics, dosage, administration schedule, and treatment duration will be determined by the treating physicians according to each patient's clinical condition. This observational study will not assign or modify treatments. Treatment exposure, subsequent treatment changes, clinical outcomes, adverse events, and medical costs will be recorded and evaluated.
28-Day All-Cause Mortality Rate
The proportion of participants who die from any cause within 28 days after the first administration of a study-defined intravenous anti-CRAB antibiotic (Day 0). Survival status will be determined using hospital medical records and follow-up assessments when necessary. The primary comparison will be between patients receiving polymyxin-based and sulbactam-based initial treatment strategies.
Time frame: From the first administration of a study-defined intravenous anti-CRAB antibiotic (Day 0) through Day 28.
Clinical Cure Rate at Day 14
The proportion of participants achieving clinical cure of the index CRAB infection at Day 14. Clinical cure is defined as resolution of infection-related symptoms, clinical signs, oxygenation or hemodynamic abnormalities, and inflammatory markers, or their return to pre-infection levels, without the need for continued or escalated targeted anti-CRAB therapy. Clinical response will be classified as cure, improvement, failure, or not evaluable.
Time frame: At Day 14 after treatment initiation, with an assessment window from Day 12 to Day 16.
Clinical Success Rate at Day 14
The proportion of participants achieving clinical success, defined as either clinical cure or clinical improvement at Day 14. Clinical improvement is defined as a substantial improvement from Day 0 in infection-related clinical findings without escalation, addition, or switching of targeted anti-CRAB therapy because of inadequate infection control. Treatment modifications due to toxicity, intolerance, drug availability, cost, renal function changes, or de-escalation after clinical cure will not automatically be classified as clinical failure. Death before the assessment time point will be classified as clinical failure.
Time frame: At Day 14 after treatment initiation, with an assessment window from Day 12 to Day 16.
Microbiological Clearance Rate
The proportion of microbiologically evaluable participants achieving microbiological clearance of CRAB from eligible infection-site specimens. Clearance is defined as the first negative follow-up culture without subsequent recovery of CRAB through the end of treatment. Two consecutive negative cultures will be additionally classified as confirmed microbiological clearance. Participants without an eligible follow-up culture will be classified as not evaluable rather than microbiologically cleared.
Time frame: Day 7 and Day 14 after Day 0, and on the date of the end of treatment (EOT)(Day 28)
Incidence of New-Onset Acute Kidney Injury
Proportion of microbiologically evaluable participants with a negative CRAB culture and no subsequent positive culture through the end of treatment. Two consecutive negative cultures will be classified as confirmed clearance.
Time frame: From treatment initiation through Day 28.
Maximum Acute Kidney Injury Stage
Highest stage of acute kidney injury observed during follow-up, classified as Stage 1, 2, or 3 according to KDIGO 2012 criteria using serum creatinine, reliable urine output, and renal replacement therapy data.
Time frame: From treatment initiation through Day 28.
Incidence of New Renal Replacement Therapy
Proportion of participants without acute kidney injury at baseline who develop acute kidney injury during follow-up, assessed according to Kidney Disease: Improving Global Outcomes (KDIGO) 2012 criteria in the prespecified evaluable population.
Time frame: From treatment initiation through Day 28.
Incidence of Adverse Events
Proportion of participants not receiving renal replacement therapy at baseline who require initiation of renal replacement therapy during the observation period.
Time frame: From treatment initiation through Day 28.
Ventilator-Free Days Within 28 Days
Number of days participants are alive and free from invasive mechanical ventilation during the first 28 days after treatment initiation. Participants who die within 28 days will be assigned zero ventilator-free days.
Time frame: During the first 28 days after treatment initiation.
Intensive Care Unit-Free Days Within 28 Days
Number of days participants are alive and not receiving care in an intensive care unit during the first 28 days. Participants who die within 28 days will be assigned zero intensive care unit-free days.
Time frame: During the first 28 days after treatment initiation
Duration of Targeted Antibiotic Therapy
Total number of days of study-defined targeted anti-CRAB antibiotic treatment received during the observation period, based on actual medication administration records.
Time frame: From treatment initiation through Day 28
Total Direct Inpatient Medical Costs
Total direct medical costs incurred during the index hospitalization within 28 days after treatment initiation, including antibiotics, intensive care, organ support, laboratory tests, diagnostic procedures, and management of adverse events. Costs will be reported in Chinese yuan.
Time frame: From treatment initiation through Day 28
Incremental Cost-Effectiveness Ratio
Incremental cost-effectiveness ratio comparing polymyxin-based and sulbactam-based initial treatment strategies, calculated as the adjusted difference in mean direct medical costs divided by the adjusted difference in 28-day survival probability. The result will be expressed in Chinese yuan per additional 28-day survivor.
Time frame: From treatment initiation through Day 28
Hospital-Free Days Within 28 Days
The number of days participants are alive and outside the hospital during the first 28 days after initiation of targeted anti-CRAB antibiotic therapy (Day 0). Participants who die within 28 days will be assigned zero hospital-free days.
Time frame: From Day 0 through Day 28.
Intensive Care Unit Length of Stay
The cumulative number of days participants spend in the intensive care unit (ICU) during the 28-day observation period after initiation of targeted anti-CRAB antibiotic therapy. ICU length of stay will be calculated using hospital admission, transfer, and discharge records.
Time frame: From Day 0 through Day 28.
Total Hospital Length of Stay
The total number of days participants spend in the hospital during the 28-day observation period, including intensive care unit and general ward stays. Hospital length of stay will be determined from hospital admission, discharge, and transfer records.
Time frame: From Day 0 through Day 28.
Targeted Antibiotic Costs
The cumulative direct costs of targeted anti-CRAB antibiotics administered during the index hospitalization within 28 days after treatment initiation. Costs will be calculated from actual medication administration and hospital billing records and reported in Chinese yuan (CNY).
Time frame: From Day 0 through Day 28.
Incidence of Clinically Significant Liver Injury
The proportion of participants developing new-onset or clinically significant worsening of liver injury after initiation of targeted anti-CRAB antibiotic therapy. Clinically significant liver injury is defined as alanine aminotransferase (ALT) or aspartate aminotransferase (AST) ≥5 times the upper limit of normal (ULN), alkaline phosphatase (ALP) ≥2 times ULN with evidence of hepatic origin, or ALT or AST ≥3 times ULN accompanied by total bilirubin ≥2 times ULN. Baseline liver abnormalities and alternative causes will be considered when assessing treatment-emergent events and drug relatedness.
Time frame: From Day 0 through Day 28.
Incidence of Neurotoxicity
The proportion of participants experiencing new-onset neurological adverse events during the observation period, including sensory disturbances, dizziness, muscle weakness, ataxia, altered consciousness, myoclonus, seizures, neuromuscular blockade, or respiratory muscle weakness. Event severity and potential relationships to antibiotic treatment will be assessed by investigators. Neurological status that cannot be reliably evaluated will be documented.
Time frame: From Day 0 through Day 28.
Incremental Net Monetary Benefit
The incremental net monetary benefit (INMB) of polymyxin-based treatment compared with sulbactam-based treatment, calculated as the willingness-to-pay threshold per additional 28-day survivor multiplied by the adjusted difference in 28-day survival probability, minus the adjusted difference in mean direct medical costs. INMB will be evaluated across prespecified willingness-to-pay thresholds and reported in Chinese yuan (CNY).
Time frame: From Day 0 through Day 28.
No study locations are listed for this record.
Plan to share: Undecided
No publications or documents are linked to this record.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
This study is not yet recruiting, as verified in Oct 2026. You cannot join it, but the record below documents what was studied.
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