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Investigating the Impact of Sepsis Phenotypes on Antibiotic Treatment in Patients With Severe Pneumonia and Sepsis

Investigating the Impact of Sepsis Phenotypes on Antibiotic Treatment in Patients With Severe Pneumonia and Sepsis: a Prospective Observational Cohort Study

Status
Not yet recruiting
Phases
Unknown
Study type
Observational
Source
ClinicalTrials.gov
Registry ID
NCT06977165
Acronym
SIPRES
Enrollment
119
Registered
2025-05-18
Start date
2025-09-01
Completion date
2027-09-30
Last updated
2025-05-18

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Infection in ICU, Pneumonia, Respiration Disorders, Respiratory Failure, Sepsis

Keywords

sepsis, pneumonia, therapeutic drug monitoring, beta-lactam antibiotics, piperacillin-tazobactam

Brief summary

Aim of the research: To find out why antibiotics work differently in certain patients with severe pneumonia and sepsis. Background: Individuals can become very unwell from pneumonia, sometimes requiring admission to hospital or even the intensive care unit (ICU). In some cases, pneumonia can lead to a condition called sepsis, which can be deadly if not treated quickly. In the UK, approximately 30,000 patients die from pneumonia every year. Clinicians use antibiotic injections to treat life-threatening infections such as severe pneumonia. After being injected into the bloodstream, antibiotics quickly spread throughout the body, attacking the infection. Antibiotics are eventually broken down and removed from the body by the kidneys and other organs. However, antibiotics fail to achieve the same consistent result for every patient. This may be to do with the way the antibiotics travel through and are removed from the body, leading to different antibiotic levels in the blood at any one time. Low antibiotic levels can result in worse outcomes and antibiotic resistance. Patients can be grouped based on how their immune system reacts to infections. The SIPRES Study aims to explore if these previously described groups explain the difference in antibiotic levels in patients with severe pneumonia and sepsis. Procedures: We will study how adult patients with severe pneumonia respond when treated with the most commonly used antibiotic in the ICU called piperacillin/tazobactam. Alongside information on how quickly patients get better and how long they need to stay in hospital or in ICU, we will collect blood samples to measure antibiotic levels and assess each patient's immune system at two time points during their treatment. This will allow us to measure antibiotic levels in blood at different times and group patients based on their immune system reaction to infection. We will describe the range of antibiotic levels seen in the different immune system reaction groups using mathematical and statistical models. Patient involvement: We are working closely with people who have experienced severe pneumonia and will work with two patient partners and a patient advisory group to help shape this research. Patient contributors have already shaped the development of the funding application and identified important study outcomes. Patients we have spoken to are concerned over the appropriate dosing of antibiotics and appreciate the need for improved and precise approaches to treating severe infections. Moving forward, patient partners will help finalise the protocol, develop patient and public facing materials, provide their perspective on the study results and shape plans to share the outcomes of the study more broadly. Potential impact: The SIPRES Study will help identify a group of patients at risk of low antibiotic levels in blood, who are less likely to improve with treatment and more likely to develop antibiotic resistance. Mathematical models that can help clinicians personalise antibiotic dosing for each critically ill patient with severe pneumonia will be developed. Findings have the potential to limit the development of antibiotic resistance and help patients survive and get better faster so that they can return to their normal daily lives. Individualised dosing for patients with low antibiotic levels, as opposed to 'one size fits all' prescribing, also has the potential to more efficiently allocate scarce resources to those who will benefit the most.

Interventions

DIAGNOSTIC_TESTAntibiotic quantification

Piperacillin/tazobactam quantification using liquid chromatography-tandem mass spectrometry

Sponsors

University of Manchester
Lead SponsorOTHER

Study design

Observational model
COHORT
Time perspective
PROSPECTIVE

Eligibility

Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No

Inclusion criteria

* age ≥ 18 years; * admitted to intensive care and receiving at least one-organ supportive care; * treated for presumed or confirmed lower respiratory infection; * receiving or about to receive piperacillin/tazobactam as part of standard clinical care; * valid informed consent or enrolment through deferred consent pathway appropriate.

Exclusion criteria

* unlikely to survive 24 hours as judged by the treating physician; * study antimicrobial started more than 24 hours prior.

Design outcomes

Primary

MeasureTime frameDescription
Serum concentrations of antimicrobialDay 0 ± Day 3-5The primary outcome of serum concentrations of antimicrobials was chosen to assess the profile of medication processing in the body between the groups of interest. Multiple blood samples are taken over the space of one dosing interval (most often 6-8 hours for piperacillin/tazobactam), which allows the calculation of an area under the concentration curve over time. For participants who remain in ICU at Visit 2 (Day 3-5) and are still receiving antimicrobials, a second sampling episode will occur. Those discharged from ICU prior will undergo only a single sampling period.

Secondary

MeasureTime frameDescription
Change in SOFA scoreFrom Day 0 to Day 3-5Difference between aggregate SOFA scores
All-cause mortalityAt Day 28Death censored at Day 28
Days alive and out of hospitalAt Day 28Defined as the number of days not in hospital at Day 28
Hospital and ICU length of stayAt Day 28Number of days in hospital/ICU
Clinical cureAt Day 28Defined as the completion of antibiotic treatment course (on or prior to Day 28) without recommencement of antibiotic therapy within 48 hours of cessation
Microbiological cureAt Day 28Defined as at least two negative cultures following proven bacterial infection and no new positive cultures at Day 28
Baseline Sequential Organ Failure Assessment score (SOFA)Day 0SOFA score at baseline
Isolated pathogensAt Day 28Proportion of participants with isolated pathogens
Emergence of resistant organismsAt Day 28Any organism resistant to antimicrobials identified through culture from any source (blood, urine, sputum, stool)
Therapeutic target attainmentAt Day 0 ± Day 3-5100% fraction of the time (fT) above the minimal inhibitory concentration \[MIC\] 100% fraction of the time (fT) above four times the minimal inhibitory concentration \[4xMIC\] Assessed for Pseudomonas aeruginosa according to latest EUCAST ECOFF breakpoints at time of analysis
Immune signatureAt Day 0 ± Day 3-5Phenotype category according to Davenport and Sinha classification
Safety and toxicity outcomesAt Day 28Any serious adverse events reported during the study period
Duration of primary course of antimicrobial treatmentAt Day 28Number of days of treatment with antimicrobial from baseline

Countries

United Kingdom

Contacts

Primary ContactJan Hansel, MD MRes
jan.hansel@manchester.ac.uk+44 161 275 1319

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026