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    Clinical Trial Results:
    Hyperpolarized xenon lung MRI in long-term COVID19

    Summary
    EudraCT number
    		 2021-006335-26
    Trial protocol
    		 DK  
    Global end of trial date
    05 Sep 2024

    Results information
    Results version number
    		 v1(current)
    This version publication date
    23 Oct 2025
    First version publication date
    23 Oct 2025
    Other versions

    Trial information

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    Trial identification
    Sponsor protocol code
    Xe-long-COVID
    Additional study identifiers
    ISRCTN number
    		 -
    US NCT number
    		 -
    WHO universal trial number (UTN)
    		 -
    Sponsors
    Sponsor organisation name
    Aarhus University
    Sponsor organisation address
    Palle Juul-Jensens Boulevard 99, Aarhus, Denmark, 8200
    Public contact
    MR Research Center, Aarhus University, cl@clin.au.dk
    Scientific contact
    MR Research Center, Aarhus University, cl@clin.au.dk
    Paediatric regulatory details
    Is trial part of an agreed paediatric investigation plan (PIP)
    No
    Does article 45 of REGULATION (EC) No 1901/2006 apply to this trial?
    No
    Does article 46 of REGULATION (EC) No 1901/2006 apply to this trial?
    No
    Results analysis stage
    Analysis stage
    Final
    Date of interim/final analysis
    05 Sep 2024
    Is this the analysis of the primary completion data?
    Yes
    Primary completion date
    29 Aug 2024
    Global end of trial reached?
    Yes
    Global end of trial date
    05 Sep 2024
    Was the trial ended prematurely?
    Yes
    General information about the trial
    Main objective of the trial
    To study lung gas uptake in long COVID19
    Protection of trial subjects
    All subject were thoroughly screened for MRI contraindications. During IMP inhalation, peripheal saturation was continuously monitored, and subjects were instructed to resume breathing if the saturation dropped below 85% or more than 5%-points.
    Background therapy
    		 -
    Evidence for comparator
    		 An age and gender matched control group was recruited to compare to the gas transfer of patients
    Actual start date of recruitment
    01 Jul 2023
    Long term follow-up planned
    No
    Independent data monitoring committee (IDMC) involvement?
    Yes
    Population of trial subjects
    Number of subjects enrolled per country
    Country: Number of subjects enrolled
    Denmark: 22
    Worldwide total number of subjects
    22
    EEA total number of subjects
    22
    Number of subjects enrolled per age group
    In utero
    0
    Preterm newborn - gestational age < 37 wk
    0
    Newborns (0-27 days)
    0
    Infants and toddlers (28 days-23 months)
    0
    Children (2-11 years)
    0
    Adolescents (12-17 years)
    0
    Adults (18-64 years)
    19
    From 65 to 84 years
    3
    85 years and over
    0

    Subject disposition

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    Recruitment
    Recruitment details
    		 Patients were contacted through the long covid-19 clinic, at the department of infectious diseases, Aarhus University hospital. Healthy through public advertisement. If a subject was interested in participation, they were contacted by sponsors representative to elaborate on the study. If still interested, a date for inclusion was set as appropriate

    Pre-assignment
    Screening details
    		 Screening was based on the patient self reported health scales with medical research council score above 2.

    Period 1
    Period 1 title
    Overall Trial (overall period)
    Is this the baseline period?
    		 Yes
    Allocation method
    Not applicable
    Blinding used
    		 Not blinded
    Blinding implementation details
    Explorative physiological study

    Arms
    Are arms mutually exclusive
    Yes

    Arm title
    		 Patients
    Arm description
    		 PAtients with Post COVID-19 Condition with MRC dyspnea above 2
    Arm type
    		 Experimental

    Investigational medicinal product name
    xenon
    Investigational medicinal product code
    PRD10485456
    Other name
    Xenon-129
    Pharmaceutical forms
    Inhalation solution
    Routes of administration
    Inhalation use
    Dosage and administration details
    For subjects of height 160 cm and above: 500 ml mixed with 500 ml nitrogen. For subjects of height 150 cm till 160 cm: 450ml mixed with 350 ml nitrogen.

    Arm title
    		 Healthy Controls
    Arm description
    		 Healthy age and gender matched controls
    Arm type
    		 Active comparator

    Investigational medicinal product name
    Xenon
    Investigational medicinal product code
    PRD10485456
    Other name
    Xenon-129
    Pharmaceutical forms
    Inhalation solution
    Routes of administration
    Inhalation use
    Dosage and administration details
    For subjects of height 160 cm and above: 500 ml mixed with 500 ml nitrogen. For subjects of height 150 cm till 160 cm: 450ml mixed with 350 ml nitrogen.

    Number of subjects in period 1
    		Patients Healthy Controls
    Started
    14
    8
    Completed
    14
    8

    Baseline characteristics

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    Baseline characteristics reporting groups
    Reporting group title
    Overall Trial
    Reporting group description
    		 -

    Reporting group values
    		 Overall Trial Total
    Number of subjects
    		 22 22
    Age categorical
    Units: Subjects
        In utero
    		 0 0
        Preterm newborn infants (gestational age < 37 wks)
    		 0 0
        Newborns (0-27 days)
    		 0 0
        Infants and toddlers (28 days-23 months)
    		 0 0
        Children (2-11 years)
    		 0 0
        Adolescents (12-17 years)
    		 0 0
        Adults (18-64 years)
    		 19 19
        From 65-84 years
    		 3 3
        85 years and over
    		 0 0
    Gender categorical
    Units: Subjects
        Female
    		 16 16
        Male
    		 6 6
    Subject analysis sets

    Subject analysis set title
    Patients
    Subject analysis set type
    		 Sub-group analysis
    Subject analysis set description
    Patients

    Subject analysis set title
    Healthy Controls
    Subject analysis set type
    		 Sub-group analysis
    Subject analysis set description
    Healthy Controls

    Subject analysis sets values
    		 Patients Healthy Controls
    Number of subjects
    14
    8
    Age categorical
    Units: Subjects
        In utero
    0
    0
        Preterm newborn infants (gestational age < 37 wks)
    0
    0
        Newborns (0-27 days)
    0
    0
        Infants and toddlers (28 days-23 months)
    0
    0
        Children (2-11 years)
    0
    0
        Adolescents (12-17 years)
    0
    0
        Adults (18-64 years)
    12
    7
        From 65-84 years
    2
    1
        85 years and over
    0
    0
    Age continuous
    Units:
        
    ( )
    ( )
    Gender categorical
    Units: Subjects
        Female
    11
    5
        Male
    3
    3

    End points

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    End points reporting groups
    Reporting group title
    Patients
    Reporting group description
    		 PAtients with Post COVID-19 Condition with MRC dyspnea above 2

    Reporting group title
    Healthy Controls
    Reporting group description
    		 Healthy age and gender matched controls

    Subject analysis set title
    Patients
    Subject analysis set type
    		 Sub-group analysis
    Subject analysis set description
    Patients

    Subject analysis set title
    Healthy Controls
    Subject analysis set type
    		 Sub-group analysis
    Subject analysis set description
    Healthy Controls

    Primary: Lung gas uptake and structure assessed with hyperpolarized xenon MRI

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    End point title
    		 Lung gas uptake and structure assessed with hyperpolarized xenon MRI
    End point description
    End point type
    Primary
    End point timeframe
    at day of examination
    End point values
    		 Patients Healthy Controls Patients Healthy Controls
    Number of subjects analysed
    12
    8
    12
    8
    Units: percent
    number (not applicable)
        RBC:M
    0.214617
    0.243863
    0.214617
    0.243863
        RBC:GAS
    0.001653
    0.001629
    0.001653
    0.001629
        M:GAS
    0.007030
    0.006251
    0.007030
    0.006251
    Statistical analysis title
    		 RBC:M
    Comparison groups
    Healthy Controls v Patients
    Number of subjects included in analysis
    20
    Analysis specification
    Pre-specified
    Analysis type
    		 equivalence
    P-value
    		 = 0.305
    Method
    		 Wilcoxon (Mann-Whitney)
    Parameter type
    		 Median difference (final values)
    Point estimate
    0.0292
    Confidence interval
         level
    		 95%
         sides
    2-sided
         lower limit
    		 -0.0191
         upper limit
    		 0.107
    Statistical analysis title
    		 RBG:GAS
    Comparison groups
    Patients v Healthy Controls v Patients v Healthy Controls
    Number of subjects included in analysis
    40
    Analysis specification
    Pre-specified
    Analysis type
    		 equivalence
    P-value
    		 = 0.97
    Method
    		 Wilcoxon (Mann-Whitney)
    Parameter type
    		 Mean difference (final values)
    Point estimate
    -0.0000087
    Confidence interval
         level
    		 95%
         sides
    2-sided
         lower limit
    		 -0.000414
         upper limit
    		 0.000492
    Statistical analysis title
    		 M:GAS
    Comparison groups
    Patients v Healthy Controls v Patients v Healthy Controls
    Number of subjects included in analysis
    40
    Analysis specification
    Pre-specified
    Analysis type
    		 equivalence
    P-value
    		 = 0.172
    Method
    		 Wilcoxon (Mann-Whitney)
    Parameter type
    		 Mean difference (final values)
    Point estimate
    -0.000779
    Confidence interval
         level
    		 95%
         sides
    2-sided
         lower limit
    		 -0.00194
         upper limit
    		 0.000377

    Secondary: Lung Mircrostrucure

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    End point title
    		 Lung Mircrostrucure
    End point description
    The Apparent Diffusion Coefficient (ADC) and the mean diffusive length scale (LmD) are measures if lung alveolar size
    End point type
    Secondary
    End point timeframe
    At time of examination
    End point values
    		 Patients Healthy Controls
    Number of subjects analysed
    10
    8
    Units: micrometre(s)
    median (inter-quartile range (Q1-Q3))
        LmD
    283.8 (272.4 to 295.1)
    297.7 (294.4 to 318.2)
        ADC
    0.035 (0.033 to 0.037)
    0.039 (0.038 to 0.043)
    Statistical analysis title
    		 ADC
    Comparison groups
    Patients v Healthy Controls
    Number of subjects included in analysis
    18
    Analysis specification
    Pre-specified
    Analysis type
    		 equivalence
    P-value
    		 = 0.012
    Method
    		 t-test, 2-sided
    Parameter type
    		 Mean difference (final values)
    Point estimate
    0.00486
    Confidence interval
         level
    		 95%
         sides
    2-sided
         lower limit
    		 0.00122
         upper limit
    		 0.0085
    Statistical analysis title
    		 LmD
    Comparison groups
    Patients v Healthy Controls
    Number of subjects included in analysis
    18
    Analysis specification
    Pre-specified
    Analysis type
    		 equivalence
    P-value
    		 = 0.013
    Method
    		 t-test, 2-sided
    Parameter type
    		 Mean difference (final values)
    Point estimate
    22.5
    Confidence interval
         level
    		 95%
         sides
    2-sided
         lower limit
    		 5.37
         upper limit
    		 39.6

    Adverse events

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    Adverse events information
    Timeframe for reporting adverse events
    On the date of examination
    Assessment type
    		 Systematic
    Dictionary used for adverse event reporting
    Dictionary name
    		 None
    Dictionary version
    0
    Reporting groups
    Reporting group title
    Patients
    Reporting group description
    		 PAtients with Post COVID-19 Condition with MRC dyspnea above 2

    Reporting group title
    Healthy Controls
    Reporting group description
    		 Healthy age and gender matched controls

    Serious adverse events
    		 Patients Healthy Controls
    Total subjects affected by serious adverse events
         subjects affected / exposed
    0 / 14 (0.00%)
    0 / 8 (0.00%)
         number of deaths (all causes)
    0
    0
         number of deaths resulting from adverse events
    0
    0
    Frequency threshold for reporting non-serious adverse events: 0%
    Non-serious adverse events
    		 Patients Healthy Controls
    Total subjects affected by non serious adverse events
         subjects affected / exposed
    8 / 14 (57.14%)
    4 / 8 (50.00%)
    Nervous system disorders
    Sensory disturbance
         subjects affected / exposed
    2 / 14 (14.29%)
    1 / 8 (12.50%)
         occurrences all number
    2
    1
    Dizziness
         subjects affected / exposed
    4 / 14 (28.57%)
    3 / 8 (37.50%)
         occurrences all number
    4
    3
    Gastrointestinal disorders
    Epigastric discomfort
    alternative assessment type: Non-systematic
         subjects affected / exposed
    1 / 14 (7.14%)
    0 / 8 (0.00%)
         occurrences all number
    1
    0
    Taste disorder
    Additional description: taste of metal
         subjects affected / exposed
    1 / 14 (7.14%)
    1 / 8 (12.50%)
         occurrences all number
    1
    1

    More information

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    Substantial protocol amendments (globally)
    Were there any global substantial amendments to the protocol? No

    Interruptions (globally)
    Were there any global interruptions to the trial? No

    Limitations and caveats
    Limitations of the trial such as small numbers of subjects analysed or technical problems leading to unreliable data.
    Study was terminated early due to slow recruitment. This lead to a smaller than desired sample size.
    For support, Contact us.
    The status and protocol content of GB trials is no longer updated since 1 January 2021. For the UK, as of 31 January 2021, EU Law applies only to the territory of Northern Ireland (NI) to the extent foreseen in the Protocol on Ireland/NI. Legal notice
    As of 31 January 2023, all EU/EEA initial clinical trial applications must be submitted through CTIS . Updated EudraCT trials information and information on PIP/Art 46 trials conducted exclusively in third countries continues to be submitted through EudraCT and published on this website.

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