Validation of Biomarkers for Long COVID in the LIINC Viral Immunopathogenesis and Persistence Repeat Donor Cohort (VIPER) (VIPER)

August 12, 2026 updated by: University of California, San Francisco

The purpose of this study is to better understand the biological changes associated with Long COVID and to identify laboratory tests (biomarkers) that may help diagnose the condition and measure how it changes over time. Researchers will enroll people with Long COVID as well as people who have fully recovered after COVID-19 infection.

Participants will provide health information and biological samples, such as blood, saliva, stool, and, for some participants, tissue biopsies. These samples will be used to study the biological processes involved in Long COVID and to support the development of new diagnostic tests that may improve future research, clinical trials, and patient care.

Study Overview

Status

Recruiting

Conditions

Detailed Description

The lack of a biomarker for Long COVID (LC) is the single biggest obstacle to the development of a cure for this disabling infection-associated chronic condition (IACC). Development of biomarkers to date has been sluggish and uncoordinated, in part due to the lack of resources invested in this effort and in part due to the lack of a central biospecimen collection, distribution, and analytic resource to support the work of laboratories who are developing compelling assays for this condition using novel technologies. Currently, the work of assay development is highly siloed - individual laboratories working with relatively small numbers of samples from participants from individual cohorts with a variable degree of clinical phenotyping are developing individual assays that have not been robustly validated or compared head-to-head with similar assays. The result has been a lack of progress in advancing Long COVID diagnostics, which in turn has limited the development of Long COVID treatments and ultimately a cure.

The UCSF Viral Immunology and Persistence Repeat Donor Cohort (VIPER) program aims to address these challenges by serving as a central, gold-standard resource to support the development of biomarkers for Long COVID. Developed within the UCSF Long-term Impact of Infection with Novel Coronavirus (LIINC) research program (UCSF IRB # 20-30479) - one of the most highly visible and productive Long COVID studies in the world - VIPER will enroll and deeply phenotype individuals with well-defined Long COVID as well as those who have fully recovered from SARS-CoV-2 infection. All participants will undergo a combination of non-invasive (blood, saliva, stool) and invasive (tissue biopsy) sampling using established procedures, with collection of ample amounts of biological specimens to support downstream biomarker development. VIPER specimens will be centrally housed and distributed to collaborating laboratories, who while blinded to the characteristics of the participants will generate measurements that are shared with a central data core for analysis. This will enable the determination of how each assay performs relative to both clinical and laboratory "gold standards" and how each assay performs relative to each other.

Following the identification and validation of these biomarkers, this program will also determine how these tests can be used to assess eligibility and outcomes in LC trials. Ultimately, the goal of VIPER is to promote the development of biomarker tests that can be utilized in the clinic setting to identify those who are likely to benefit from therapeutics targeting each of the mechanisms of Long COVID.

Study Type

Observational

Enrollment (Estimated)

150

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact Backup

Study Locations

  • United States
    • California
      • San Francisco, California, United States, 94110
        • Recruiting
        • Zuckerberg San Francisco General Hospital
        • Contact:
        • Principal Investigator:
          • Michael Peluso

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

Yes

Sampling Method

Non-Probability Sample

Study Population

The study population will include adults with well-characterized Long COVID and adults who have recovered following SARS-CoV-2 infection. Participants will be enrolled from the UCSF Long-term Impact of Infection with Novel Coronavirus (LIINC) research program and through community outreach and referral efforts. The study aims to include individuals with a range of Long COVID symptom patterns and durations to support research on the biological mechanisms of the condition.

Description

Inclusion Criteria:

  • Willing and able to provide written informed consent, and
  • Age >/= 18 years, and
  • Either:

History of a SARS-CoV-2 infection resulting in Long COVID symptoms, confirmed by the investigator, or

Exposure to SARS-CoV-2 without establishment of Long COVID.

  • Enrolled or willing to enroll and complete at least 1 visit in the UCSF Long-term Impact of Infection with Novel Coronavirus (LIINC).
  • Enrolled or willing to be referred for a gut biopsy procedure under related IRB-approved protocols.

Exclusion Criteria:

  • Self-reported or documented chronic anemia with hemoglobin < 9 g/dL. Anemia during a preceding acute illness will not be exclusionary.
  • Serious medical or psychiatric illness that, in the opinion of the site investigator, would interfere with the ability to adhere to study requirements or to give informed consent.
  • Presence of a condition or abnormality that in the opinion of the Investigator would compromise the safety of the patient or the quality of the data.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

Cohorts and Interventions

Group / Cohort
Long COVID
People experiencing Long COVID symptoms
Recovered
People who have fully recovered from their COVID infection(s)

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Participant sex
Time Frame: Baseline visit
The proportion of men and women participating in the baseline visit.
Baseline visit
Participant age
Time Frame: Baseline visit
The median age of study participants at enrollment
Baseline visit
Participant race/ethnicity
Time Frame: Baseline visit
The proportion of participants from each demographic group
Baseline visit
Proportion of participants previously hospitalized
Time Frame: Baseline visit
The proportion of participants who were previously hospitalized
Baseline visit
Colonoscopy Completed
Time Frame: Baseline visit
The proportion of participants completing a research colonoscopy for the study
Baseline visit

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Protocol complete
Time Frame: Up to 6 weeks from baseline
The proportion of enrolled participants who complete all study activities
Up to 6 weeks from baseline

Other Outcome Measures

Outcome Measure
Measure Description
Time Frame
Long COVID Symptom Assessment
Time Frame: Screening, baseline, and up to 6 weeks
Participant-reported assessment for presence and severity of persistent post-COVID-19 symptoms
Screening, baseline, and up to 6 weeks
Qualify of Life Assessment (Global Health Score)
Time Frame: Screening, baseline, and up to 6 weeks
Measure of overall health-related quality of life
Screening, baseline, and up to 6 weeks
Mental Health Symptom Assessment
Time Frame: Screening visit
An instrument such as the PHQ-9 will be used to assess participants' overall mental health status. These will include questions about anxiety and depression, independent of Long COVID association.
Screening visit
Cognitive Symptom Assessment
Time Frame: Screening visit
An instrument such as the Everyday Cognition survey will be used to asses perceived changes in everyday cognitive function across domains compared to participants' pre-COVID baselines.
Screening visit
Fatigue Symptom Assessment
Time Frame: Baseline and up to 6 weeks
An instrument such as the FACIT-Fatigue will be used to assess fatigue severity and its impact on daily activities.
Baseline and up to 6 weeks
Gastrointestinal Symptom Assessment
Time Frame: Baseline and up to 6 weeks
An instrument such as the Modified Gastrointestinal Symptom Rating Scale (GSRS) will be used to assess the severity of gastrointestinal symptoms across multiple symptom domains.
Baseline and up to 6 weeks
Neurocognitive Function Assessment
Time Frame: Baseline and up to 6 weeks
A computer-based neurocognitive test such as CNS Vital Signs will be used to assess cognitive function across multiple domains including memory, attention, psychomotor speed, and executive function.
Baseline and up to 6 weeks
Physical Function Symptom Assessment
Time Frame: Baseline and up to 6 weeks
An instrument such as the PROMIS Physical Function will be used to assess participants' ability to perform physical activities of daily living.
Baseline and up to 6 weeks
Autonomic Symptom Assessment
Time Frame: Baseline and up to 6 weeks
A questionnaire such as the COMPASS-31 or Orthostatic Hypotension Questionnaire (OHQ) will be used to assess autonomic nervous system symptoms across symptom domains.
Baseline and up to 6 weeks
Post-Exertional Malaise Symptom Assessment
Time Frame: Baseline and up to 6 weeks
An instrument such as the DSQ-PEM will be used to assess the severity of post-exertional malaise
Baseline and up to 6 weeks
Grip Strength Test
Time Frame: Up to 6 weeks from baseline
Objective measure of hand grip strength using a hand dynamometer
Up to 6 weeks from baseline
30-Second Sit-to-Stand Test
Time Frame: Up to 6 weeks from baseline
Objective performance test measuring the number of full stands from a seated position completed in 30 seconds
Up to 6 weeks from baseline
Active Standing Test
Time Frame: Up to 6 weeks from baseline
Objective measurement of changes in heart rate and blood pressure upon transition from lying/sitting to standing
Up to 6 weeks from baseline

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

University of California, San Francisco

Collaborators

PolyBio Research Foundation

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

May 18, 2026

Primary Completion (Estimated)

May 15, 2031

Study Completion (Estimated)

May 15, 2031

Study Registration Dates

First Submitted

August 7, 2026

First Submitted That Met QC Criteria

August 12, 2026

First Posted (Actual)

August 18, 2026

Study Record Updates

Last Update Posted (Actual)

August 18, 2026

Last Update Submitted That Met QC Criteria

August 12, 2026

Last Verified

August 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • 25-45159

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

UNDECIDED

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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