Pine bark pill tested for long COVID relief in 153 patients
NCT ID NCT05890534
First seen Jun 27, 2026 · Last updated Jun 27, 2026
Summary
This study tested Pycnogenol, a natural pine bark extract, against a placebo in 153 adults with Long COVID. The goal was to see if it improves overall health and reduces symptoms like fatigue and brain fog. Participants took the supplement for 12 weeks and reported their health status daily.
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Study facts
What this study's own registry entry says, in plain language.
- Phase
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Phase 3
Large-scale testing in a bigger group. Usually the last step before a treatment can be approved.
- Participants
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153 people
The number who actually took part.
- Started
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Jun 2023
- Finished
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Jan 2025
- Lead sponsor
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Other sponsor
The registry's catch-all category, for sponsors it does not file as a company, a government agency, or a research network.
Who can take part
This study's own entry requirements. Only the study team can say for certain whether you qualify.
- Ages
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18 years and older
- Sex
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Anyone
- Healthy volunteers
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Not accepted
This study is not open to healthy volunteers. The entry requirements below say who it is open to.
Show the full entry requirements Hide the full entry requirements
Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.
Inclusion Criteria: * SARS-CoV-2 infection confirmed by positive PCR or rapid antigen test for professional use or written medical report * Post-COVID condition (WHO definition), i.e., ≥ 3 months after SARS-CoV2 infection and ongoing or recurring symptoms for at least 2 months that cannot be explained by alternative diagnosis * Symptoms include fatigue and / or cognitive impairment ("brain fog") and / or dyspnea and / or post-exertional malaise * Willing to participate and having signed informed consent * Sufficient language and cognitive skills * Ability to participate in study visits * No foreseeable change in medication Exclusion Criteria: * Severe comorbidities such as liver or renal failure, advanced COPD or pulmonary fibrosis requiring \> 5L oxygen/min at rest, active malignancy, advanced heart failure, cardio-vascular events within the previous 24 weeks (such as unstable coronary artery disease, coronary revascularization, myocardial infarction, stroke, transient ischemic attack, critical limb ischemia, pulmonary embolism, deep vein thrombosis), uncontrolled severe hypertension, uncontrolled diabetes uncontrolled autoimmune or inflammatory disease (the responsible study physician will decide each case on an individual basis) * Acute respiratory or other infections (postpone baseline visit until resolved) * Clinical diagnosis of a psychiatric disease (e.g., depression, anxiety disorder, schizophrenia) that is untreated and/or unstable (the responsible study physician will decide each case on an individual basis) * COVID-19 vaccination less than 4 weeks prior to the baseline visit (i.e., first or second dose of a two-dose vaccination regimen, first dose of a single dose vaccination regimen, booster) or during study participation (booster shot will be offered at screening visit, wait time until baseline visit 4 weeks) * Known intolerance of the study drug * Regular intake of Pycnogenol® * Pregnancy or lactating. For women and transgender individuals of childbearing age, who can anamnestically not exclude a pregnancy, are offered a pregnancy test during the study visits. * Being enrolled in another interventional study that may interfere with the current study (the responsible study physician will decide each case on an individual basis)
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Conditions
The condition(s) this trial relates to.
As listed by the trial registrant
The condition terms exactly as the trial's registrant entered them.
Contacts and locations
Locations
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University of Zurich, Epidemiology, Biostatistics and Prevention Institute, Department of Public & Global Health
Zurich, 8001, Switzerland
More trials for these conditions
Other studies related to the condition(s) this trial covers.
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- Mindfulness may offer relief for long COVID sufferers
- Can wearables decode the mystery of fatigue?
- Beetroot juice: a natural boost against long COVID fatigue?
- A One-Two punch for long COVID? supplement and therapy put to the test