Long COVID SyndromeNCT04793269
Characteristics of Long COVID-19 Syndrome
An observational study of Long COVID Syndrome, run by Christian Clarenbach at 1 site in Switzerland.
Trial summary
Characterization of patients with long COVID syndrome including symptoms, medical history and persistent organ damage. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Long COVID Syndrome
- How many people
- 200 participants
- Where
- 1 siteSwitzerland
- Study dates
- 23 Feb 2021to 31 Dec 2025
- 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 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Study population: Patients with long COVID syndrome
Who may be able to join
- Long COVID syndrome
- age >= 18 years
- Informed consent
Who cannot join
- none
Trial locations and contacts
1 site in 1 country.
Switzerland1 site
University Hospital Zurich
Zurich, Canton of Zurich, 8091
About this study
Official title: Long COVID Syndrom: Charakterisierung Eines Neuen Krankheitsbildes
Characterization of patients with long COVID syndrome including symptoms, medical history and persistent organ damage.
Read the detailed description
Some people are very hesitant to recover from a COVID-19 infection and present persistent symptoms. The participants still suffer after the acute phase of the infection from shortness of breath, coughing, chest pain or fatigue. Therefore, a special interdisciplinary consultation was built. The consulatation is not only addressed to people who have been hospitalized due to COVID-19, but also to those with mild symptoms during infection. During the consultation hours, personal health data are collected that serves as the basis for this research project.
- Conditions
- Long COVID Syndrome
- Being tested
- No intervention
- Keywords
- long COVID, post COVID
- Medical subject headings
- Post-Acute COVID-19 Syndrome
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
No interventionOther
no intervention
| Study group | Role | What they receive |
|---|---|---|
| Long COVID | Patients with long COVID syndrome Receives: Other: No intervention |
What is being measured
The primary outcome is the main question the study is designed to answer.
Dyspnea
modified medical research council (scale from 0 to 4). The higher the score the worse the symptoms.
Measured: once through study completion, an average of 6 months.
self-addressed Quality of life
Short form health 36 questionnaire with 8 domains, each rated from 0-100. The higher the score the better subjective quality of life.
Measured: once through study completion, an average of 6 months
Thoracic pain
assessed by medical interview (reported as yes or no)
Measured: once through study completion, an average of 6 months
Medical history
List of relevant morbidities assessed as present/not present by medical interview (e.g. respiratory, cardial, neurological, psychiatric diseases by interview and medical records)
Measured: once through study completion, an average of 6 months
Fibrosis
Assessed by chest CT, rated as present/not present
Measured: once through study completion, an average of 6 months
Myocardial damage
Assessed by myocardial damage, rated as present/not present
Measured: once through study completion, an average of 6 months
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted11 Mar 2021
- Study start23 Feb 2021
- Primary completion31 Dec 2025 (estimated)
- Study completion31 Dec 2025 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (1)Papers the sponsor has linked to this study.
- Other trials for Long COVID SyndromeStudies of the same condition, open and under way.
- 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
- Retrospective
- Enrolment
- 200 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Christian Clarenbach
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor-investigator, Christian Clarenbach, University of Zurich
- Investigators
- Christian F Clarenbach, MD, Study chair, University Hospital Zurich, Pulmonology
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT04793269
- Sponsor's protocol ID
- 2021-00280
- Status last verified
- Mar 2025
- First submitted
- 4 Mar 2021
- Last updated
- 30 Mar 2025
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No: IPD will be shared on request
Publications
Malesevic S, Sievi NA, Baumgartner P, Roser K, Sommer G, Schmidt D, Vallelian F, Jelcic I, Clarenbach CF, Kohler M. Impaired health-related quality of life in long-COVID syndrome after mild to moderate COVID-19. Sci Rep. 2023 May 12;13(1):7717. doi: 10.1038/s41598-023-34678-8.
PubMed 37173355
Study at a glance
From the registry record, last updated by the sponsor on 30 Mar 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Long COVID Syndrom: Charakterisierung Eines Neuen Krankheitsbildes
- ClinicalTrials.gov ID
- NCT04793269
- Acronym / sponsor ID
- 2021-00280
- Conditions
- Long COVID Syndrome
- Keywords
- long COVID, post COVID
- Study type
- Observational
- Recruitment status
- Active, not recruiting
- Enrolment
- 200 participants (estimated)
- Lead sponsor
- Christian ClarenbachUniversity, hospital or other
- Study start
- 23 Feb 2021 (actual)
- Primary completion
- 31 Dec 2025 (estimated)
- Study completion
- 31 Dec 2025 (estimated)
- First posted
- 11 Mar 2021 (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.
Characterization of patients with long COVID syndrome including symptoms, medical history and persistent organ damage.
Detailed description
Some people are very hesitant to recover from a COVID-19 infection and present persistent symptoms. The participants still suffer after the acute phase of the infection from shortness of breath, coughing, chest pain or fatigue. Therefore, a special interdisciplinary consultation was built. The consulatation is not only addressed to people who have been hospitalized due to COVID-19, but also to those with mild symptoms during infection. During the consultation hours, personal health data are collected that serves as the basis for this research project.
Study design
- Observational model
- Cohort
- Time perspective
- Retrospective
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| Long COVID | – | Other: No interventionPatients with long COVID syndrome |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
- Study population
- Patients with long COVID syndrome
Key inclusion criteria (3 listed)
- Long COVID syndrome
- age >= 18 years
- Informed consent
Key exclusion criteria (1 listed)
- none
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 |
|---|---|---|
| No interventionno intervention | Other | Long COVID |
Primary outcome
Dyspnea
Time frame: once through study completion, an average of 6 months.
modified medical research council (scale from 0 to 4). The higher the score the worse the symptoms.
self-addressed Quality of life
Time frame: once through study completion, an average of 6 months
Short form health 36 questionnaire with 8 domains, each rated from 0-100. The higher the score the better subjective quality of life.
Thoracic pain
Time frame: once through study completion, an average of 6 months
assessed by medical interview (reported as yes or no)
Medical history
Time frame: once through study completion, an average of 6 months
List of relevant morbidities assessed as present/not present by medical interview (e.g. respiratory, cardial, neurological, psychiatric diseases by interview and medical records)
Fibrosis
Time frame: once through study completion, an average of 6 months
Assessed by chest CT, rated as present/not present
Myocardial damage
Time frame: once through study completion, an average of 6 months
Assessed by myocardial damage, rated as present/not present
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 30 Mar 2025.
- Derived from this study: PubMed 37173355Malesevic S, Sievi NA, Baumgartner P, Roser K, Sommer G, Schmidt D, Vallelian F, Jelcic I, Clarenbach CF, Kohler M. Impaired health-related quality of life in long-COVID syndrome after mild to moderate COVID-19. Sci Rep. 2023 May 12;13(1):7717. doi: 10.1038/s41598-023-34678-8.
- Individual participant dataSharing planned: No. IPD will be shared on request
Related trials for Long COVID Syndrome
Not yet recruitingPhase 1
Phase I Open-Label Safety Trial of Pembrolizumab for Neurological Post- Acute Sequelae of SARS-CoV-2 (PD1-PASC I)
Post-Acute COVID-19 Syndrome
Recruiting
Whole-body Cryotherapy in Those With Chronic Fatigue: A Feasibility Study
ME/CFS, Fibromyalgia (FM)
Not yet recruitingPhase 3
The Study of Brave-LC LDN Treatment Trial
Post-acute COVID-19 Syndrome
Active, not recruitingObservational study
Epigenetic Changes in Long COVID Patients
Long COVID-19 Syndrome, Long COVID Symptoms
Enrolling by invitationPhase 2
Immunotherapy for Neurological Post-Acute Sequelae of SARS-CoV-2
Systemic Inflammation, Neuroinflammation
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. This study is not recruiting at the moment.
Christian F Clarenbach, MD study chair
University Hospital Zurich, Pulmonology
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 Long COVID Syndrome, run by Christian Clarenbach at 1 site in Switzerland.
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 3 inclusion and 1 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: under way, not looking for participants, as of the sponsor's last update on 30 Mar 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 Switzerland. 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?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Dyspnea (time frame: once through study completion, an average of 6 months.). The study lists 6 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT04793269, which also lists 1 linked publication.
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 30 Mar 2025.