Critical IllnessNCT07301970
Population Pharmacokinetics of Remifentanil in Low-Weight Critically Ill Patients
An observational study of Critical Illness and Pain, run by Fudan University at 1 site in China.
Trial summary
The goal of this prospective clinical study is to learn about the population pharmacokinetics (PopPK), safety, and efficacy of remifentanil in low-body-weight patients in the Intensive Care Unit (ICU) who require mechanical ventilation. The main questions it aims to answer are: 1. Read more about this study
- Who is it for?
- Any age
- Conditions the study is for
- Critical Illness, Pain
- What is being tested?
- Remifentanil
- Type of treatment
- Injection or infusion
- How many people
- 45 participants
- Where
- 1 siteChina
- Study dates
- 22 Sep 2025to 30 Nov 2026
- How long will I take part?
- 7 Days
- Phase
- Observational
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages Any age
- All sexes
- No healthy volunteers
- Child, Adult, Older adult
Study population: Adult patients admitted to the Intensive Care Unit (ICU) requiring invasive mechanical ventilation who receive remifentanil for analgesia and sedation. The study population comprises two cohorts stratified by Body Mass Index (BMI): a low-body-weight group (BMI < 18.5 kg/m²) and a normal-body-weight control group (18.5 kg/m² ≤ BMI < 24 kg/m²).
Who may be able to join
- Age: ≥18 years old, regardless of sex;
- Normal weight: 18.5 kg/m² ≤ Body Mass Index (BMI) < 24 kg/m² or Low weight: BMI < 18.5 kg/m²;
- Admitted to the intensive care unit (ICU);
- Required invasive mechanical ventilation for more than 10 hours;
- The subject or their legal guardian has fully understood the potential risks and benefits of participating in this study and has signed the informed consent form.
Who cannot join
- Pregnant women;
- Presence of severe respiratory impairment or respiratory depression during the screening period;
- Known hypersensitivity to remifentanil or any of the excipients;
- Meeting other contraindications for opioid use
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
China1 site, 1 recruiting
- Recruiting
Shanghai Minhang Central Hospital
Shanghai
Xiang Li, -86-21-64923400, xiangli0159@hotmail.com
About this study
Official title: Population Pharmacokinetics of Remifentanil for Analgesia and Sedation in Low-Weight Critically Ill Patients Receiving Mechanical Ventilation
The goal of this prospective clinical study is to learn about the population pharmacokinetics (PopPK), safety, and efficacy of remifentanil in low-body-weight patients in the Intensive Care Unit (ICU) who require mechanical ventilation. The main questions it aims to answer are:
- What are the pharmacokinetic characteristics of remifentanil in low-weight ICU patients?
- How does remifentanil (and concurrent propofol use) affect hemodynamic stability (such as blood pressure) and sedation efficacy in this population?
Participants receiving mechanical ventilation will receive remifentanil for analgesia and sedation according to a standardized protocol. They will undergo arterial blood sampling at specific time points to measure drug concentrations. Researchers will also record hemodynamic parameters. Additionally, a subset of patients receiving propofol as a rescue sedative will have plasma propofol concentrations measured to evaluate its influence on blood pressure changes.
Read the detailed description
- Background: Remifentanil is a lipophilic μ-opioid receptor agonist characterized by rapid onset and offset, making it ideal for analgosedation in the Intensive Care Unit (ICU). Body weight is a significant factor affecting its pharmacokinetics (PK). Low-body-weight patients may require different dosing strategies. This study aims to establish a population pharmacokinetic (PopPK) model for remifentanil in mechanically ventilated patients with low body weight and to evaluate its safety and efficacy, with a specific focus on hemodynamic stability.
- Study Protocol \& Dosing Strategy: This is a single-center, prospective observational study designed to reflect real-world clinical practice. Eligible patients requiring invasive mechanical ventilation will receive remifentanil for analgesia and sedation.
- Co-administration: In accordance with standard ICU practice, remifentanil is often administered concurrently with propofol to ensure adequate sedation and analgesia.
- Dosing Regimen: The administration of a loading dose is discretionary based on the patient's clinical condition; in many cases, a continuous infusion is initiated directly without a loading dose to maintain hemodynamic stability.
- Infusion Rate: The continuous infusion is typically initiated at a standardized clinical rate (e.g., approximately 0.18 mg/h) or a weight-based equivalent.
- Titration: Subsequent dosing is titrated dynamically based on clinical response (e.g., patient comfort, ventilator synchrony) and hemodynamic tolerance.
- Pharmacokinetic Sampling (Sparse \& Opportunistic): Blood samples are not collected at rigid clock times but are distributed to capture key PK phases:
- Absorption/Distribution Phase: Samples collected within the first hour of infusion (e.g., 1-2 samples).
- Steady State: Samples collected during stable continuous infusion.
- Elimination Phase: Samples collected immediately prior to stopping the infusion and at multiple intervals after discontinuation.
5.Hemodynamic Assessment \& Propofol Co-variate Analysis: Hemodynamic parameters (MAP, HR) are continuously monitored. Given that propofol is co-administered in most patients and significantly impacts hemodynamics, plasma propofol concentrations will be measured in a subset of patients. These data will be incorporated into the PopPK/PD analysis as a covariate to distinguish the hemodynamic effects of remifentanil from those of propofol.
- Conditions
- Critical Illness, Pain
- Being tested
- Remifentanil
- Medical subject headings
- Critical Illness, Pain
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
RemifentanilDrug
Patients receive remifentanil for analgesia and sedation during mechanical ventilation. The administration follows standard ICU clinical practice, typically initiated at a continuous infusion rate (e.g., approximately 0.18 mg/h or weight-based equivalent) and titrated based on patient response.
| Study group | Role | What they receive |
|---|---|---|
| Low-weight group | BMI < 18.5 Receives: Drug: Remifentanil | |
| Normal-weight group | 18.5 ≤ BMI< 24 Receives: Drug: Remifentanil |
What is being measured
The primary outcome is the main question the study is designed to answer.
Plasma Concentration of Remifentanil
Peripheral arterial blood samples (1mL each) drawn from an existing indwelling arterial blood pressure (ABP) catheter will be collected to determine the plasma concentration of remifentanil (unit: ng/mL). A sparse and opportunistic sampling strategy is employed to capture the full pharmacokinetic profile. Sampling points typically include:
- Absorption/Distribution Phase: Approximately 2 samples within the first 2 hours of administration;
- Maintenance Phase: Samples collected during steady-state infusion, and following dose adjustments to capture the new steady state (typically after re-equilibration);
- Elimination Phase: Approximately 3 samples within 2 hours after the end of infusion.
Measured: From the start of remifentanil administration, through the maintenance infusion phase, up to 2 hours after the end of infusion.
Secondary outcomes (3)
Mean Arterial Pressure (MAP)
Evaluation of hemodynamic stability by measuring the absolute value of MAP. Reported in mmHg.
Measured: From baseline throughout the duration of drug infusion (up to approximately 48 hours).
Plasma Concentration of Propofol
Plasma propofol concentrations will be measured in the subset of patients who receive propofol as a rescue sedative or co-medication. This data will be used as a covariate in the PK/PD analysis to differentiate the hemodynamic effects of propofol from those of remifentanil.
Measured: From the start of its administration, through the maintenance infusion phase, up to 2 hours after the end of infusion.
Heart Rate
Evaluation of hemodynamic stability by measuring Heart Rate. Reported in beats per minute.
Measured: From baseline throughout the duration of drug infusion (up to approximately 48 hours).
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted24 Dec 2025
- Study start22 Sep 2025
- Primary completion30 Jun 2026 (estimated)
- Study completion30 Nov 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Critical IllnessStudies of the same condition, open and under way.
- More trials run by Fudan UniversityThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Cohort
- Time perspective
- Prospective
- Enrolment
- 45 participants (estimated)
- Target duration
- 7 Days
Sponsor and investigators
- Lead sponsor
- Fudan University
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Xiang Li, Shanghai Minhang Central Hospital
- Investigators
- Xiang Li, Principal investigator, Shanghai Minhang Central Hospital
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07301970
- Sponsor's protocol ID
- 2025-007-01K
- Status last verified
- Sep 2025
- First submitted
- 29 Nov 2025
- Last updated
- 24 Dec 2025
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No: Individual participant data will not be shared due to privacy restrictions and ethical considerations.
Study at a glance
From the registry record, last updated by the sponsor on 24 Dec 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Population Pharmacokinetics of Remifentanil for Analgesia and Sedation in Low-Weight Critically Ill Patients Receiving Mechanical Ventilation
- ClinicalTrials.gov ID
- NCT07301970
- Acronym / sponsor ID
- 2025-007-01K
- Conditions
- Critical Illness, Pain
- Study type
- Observational
- Recruitment status
- Recruiting
- Enrolment
- 45 participants (estimated)
- Lead sponsor
- Fudan UniversityUniversity, hospital or other
- Study start
- 22 Sep 2025 (actual)
- Primary completion
- 30 Jun 2026 (estimated)
- Study completion
- 30 Nov 2026 (estimated)
- First posted
- 24 Dec 2025 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The goal of this prospective clinical study is to learn about the population pharmacokinetics (PopPK), safety, and efficacy of remifentanil in low-body-weight patients in the Intensive Care Unit (ICU) who require mechanical ventilation. The main questions it aims to answer are:
- What are the pharmacokinetic characteristics of remifentanil in low-weight ICU patients?
- How does remifentanil (and concurrent propofol use) affect hemodynamic stability (such as blood pressure) and sedation efficacy in this population?
Participants receiving mechanical ventilation will receive remifentanil for analgesia and sedation according to a standardized protocol. They will undergo arterial blood sampling at specific time points to measure drug concentrations. Researchers will also record hemodynamic parameters. Additionally, a subset of patients receiving propofol as a rescue sedative will have plasma propofol concentrations measured to evaluate its influence on blood pressure changes.
Detailed description
- Background: Remifentanil is a lipophilic μ-opioid receptor agonist characterized by rapid onset and offset, making it ideal for analgosedation in the Intensive Care Unit (ICU). Body weight is a significant factor affecting its pharmacokinetics (PK). Low-body-weight patients may require different dosing strategies. This study aims to establish a population pharmacokinetic (PopPK) model for remifentanil in mechanically ventilated patients with low body weight and to evaluate its safety and efficacy, with a specific focus on hemodynamic stability.
- Study Protocol \& Dosing Strategy: This is a single-center, prospective observational study designed to reflect real-world clinical practice. Eligible patients requiring invasive mechanical ventilation will receive remifentanil for analgesia and sedation.
- Co-administration: In accordance with standard ICU practice, remifentanil is often administered concurrently with propofol to ensure adequate sedation and analgesia.
- Dosing Regimen: The administration of a loading dose is discretionary based on the patient's clinical condition; in many cases, a continuous infusion is initiated directly without a loading dose to maintain hemodynamic stability.
- Infusion Rate: The continuous infusion is typically initiated at a standardized clinical rate (e.g., approximately 0.18 mg/h) or a weight-based equivalent.
- Titration: Subsequent dosing is titrated dynamically based on clinical response (e.g., patient comfort, ventilator synchrony) and hemodynamic tolerance.
- Pharmacokinetic Sampling (Sparse \& Opportunistic): Blood samples are not collected at rigid clock times but are distributed to capture key PK phases:
- Absorption/Distribution Phase: Samples collected within the first hour of infusion (e.g., 1-2 samples).
- Steady State: Samples collected during stable continuous infusion.
- Elimination Phase: Samples collected immediately prior to stopping the infusion and at multiple intervals after discontinuation.
5.Hemodynamic Assessment \& Propofol Co-variate Analysis: Hemodynamic parameters (MAP, HR) are continuously monitored. Given that propofol is co-administered in most patients and significantly impacts hemodynamics, plasma propofol concentrations will be measured in a subset of patients. These data will be incorporated into the PopPK/PD analysis as a covariate to distinguish the hemodynamic effects of remifentanil from those of propofol.
Study design
- Observational model
- Cohort
- Time perspective
- Prospective
- Target follow-up
- 7 Days
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Low-weight group | – | Drug: RemifentanilBMI < 18.5 |
| Normal-weight group | – | Drug: Remifentanil18.5 ≤ BMI< 24 |
Who may qualify
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Child, Adult, Older adult
- Study population
- Adult patients admitted to the Intensive Care Unit (ICU) requiring invasive mechanical ventilation who receive remifentanil for analgesia and sedation. The study population comprises two cohorts stratified by Body Mass Index (BMI): a low-body-weight group (BMI < 18.5 kg/m²) and a normal-body-weight control group (18.5 kg/m² ≤ BMI < 24 kg/m²).
Key inclusion criteria (5 listed)
- Age: ≥18 years old, regardless of sex;
- Normal weight: 18.5 kg/m² ≤ Body Mass Index (BMI) < 24 kg/m² or Low weight: BMI < 18.5 kg/m²;
- Admitted to the intensive care unit (ICU);
- Required invasive mechanical ventilation for more than 10 hours;
- The subject or their legal guardian has fully understood the potential risks and benefits of participating in this study and has signed the informed consent form.
Key exclusion criteria (4 listed)
- Pregnant women;
- Presence of severe respiratory impairment or respiratory depression during the screening period;
- Known hypersensitivity to remifentanil or any of the excipients;
- Meeting other contraindications for opioid use
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| RemifentanilPatients receive remifentanil for analgesia and sedation during mechanical ventilation. The administration follows standard ICU clinical practice, typically initiated at a continuous infusion rate (e.g., approximately 0.18 mg/h or weight-based equivalent) and titrated based on patient response. | Drug | Low-weight group, Normal-weight group |
Primary outcome
Plasma Concentration of Remifentanil
Time frame: From the start of remifentanil administration, through the maintenance infusion phase, up to 2 hours after the end of infusion.
Peripheral arterial blood samples (1mL each) drawn from an existing indwelling arterial blood pressure (ABP) catheter will be collected to determine the plasma concentration of remifentanil (unit: ng/mL). A sparse and opportunistic sampling strategy is employed to capture the full pharmacokinetic profile. Sampling points typically include: 1. Absorption/Distribution Phase: Approximately 2 samples within the first 2 hours of administration; 2. Maintenance Phase: Samples collected during steady-state infusion, and following dose adjustments to capture the new steady state (typically after re-equilibration); 3. Elimination Phase: Approximately 3 samples within 2 hours after the end of infusion.
3 secondary outcomes
Mean Arterial Pressure (MAP)
Time frame: From baseline throughout the duration of drug infusion (up to approximately 48 hours).
Plasma Concentration of Propofol
Time frame: From the start of its administration, through the maintenance infusion phase, up to 2 hours after the end of infusion.
Heart Rate
Time frame: From baseline throughout the duration of drug infusion (up to approximately 48 hours).
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 24 Dec 2025.
- Individual participant dataSharing planned: No. Individual participant data will not be shared due to privacy restrictions and ethical considerations.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Xiang Li principal investigator
Shanghai Minhang Central Hospital
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Critical Illness and Pain, run by Fudan University at 1 site in China.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 5 inclusion and 4 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 24 Dec 2025. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in China. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Xiang Li (+86 18918169826, xiangli0159@hotmail.com), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Plasma Concentration of Remifentanil (time frame: From the start of remifentanil administration, through the maintenance infusion phase, up to 2 hours after the end of infusion.). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 24 Dec 2025.