Tier 2 — strong

Possible Therapeutic Effects of Adjuvant Quercetin Supplementation Against Early-Stage COVID-19 Infection: A Prospective, Randomized, Controlled, and Open-Label Study

Francesco Di Pierro, Giuseppe Derosa, Pamela Maffioli, Alexander Bertuccioli, Stefano Togni, Antonella Riva, Pietro Allegrini, Amjad Khan, Saeed Khan, Bilal Ahmad Khan, Naireen Altaf, Maria Zahid, Ikram Din Ujjan, Roohi Nigar, Mehwish Imam Khushk, Maryam Phulpoto, Amanullah Lail, Bikha Ram Devrajani, Sagheer Ahmed
International journal of general medicine 2021 14:2359-2366

Bibliography

PubMed
PMID 34135619
PubMed Central
PMC8197660
DOI
10.2147/IJGM.S318720
Funding
Funding was not specified in the indexed record or the disclosure metadata available for this entry.
Competing interests
Reported disclosure: FDP is a member of the Scientific Board of Pharmextracta. AB provided scientific advice to Pharmextracta S.p.A. PA, ST and AR are employees of and belong to the Scientific Board of Indena. AR reports a pending patent WO2019016146A1 for quercetin phytosome. The authors report no other conflicts of interest in this work.

Study snapshot

DesignRandomized open-label adjunctive trial
ModelHuman intervention research
Sample152 COVID-19 outpatients
InterventionQuercetin Phytosome formulation 1,000 mg/day plus usual care
Duration30 days
EndpointsEvents and survival

What the study showed, in plain terms

Published in 2021, this source examined immunity and respiratory health. Design: Randomized open-label adjunctive trial. Sample/model: 152 COVID-19 outpatients. The exposure or intervention was Quercetin Phytosome formulation 1,000 mg/day plus usual care. Follow-up or treatment period: 30 days.

The authors reported fewer hospitalizations and severe outcomes in the supplement group.

Unblinded product-specific trial with limited event counts. Confirmatory blinded trials are needed; formulation mass is not pure-quercetin mass.

Continue with Quercetin Data Center

For topic-level interpretation, read Quercetin for Immune Health, Colds and COVID-19. This is a related guide; the citation panel separately identifies articles that directly cite this paper.

Key findings

  • The authors reported fewer hospitalizations and severe outcomes in the supplement group.
  • The recorded outcome domains were Events and survival.
  • The result applies to the tested exposure: Quercetin Phytosome formulation 1,000 mg/day plus usual care; 30 days.

What this study can and cannot tell us

  • Unblinded product-specific trial with limited event counts. Confirmatory blinded trials are needed; formulation mass is not pure-quercetin mass.
  • Without a sufficiently blinded concurrent control, time effects, expectations, co-interventions and regression toward the mean can explain part of an apparent improvement.
  • Source basis: Source check: accessible full text and indexed metadata. Missing method details, funding information or participant denominators are not inferred.

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The therapeutic efficacy of quercetin in combination with antiviral drugs in hospitalized COVID-19 patients: A randomized controlled trial
Mojtaba Shohan et al. · European journal of pharmacology · 2022
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Oral Co-Supplementation of Curcumin, Quercetin, and Vitamin D3 as an Adjuvant Therapy for Mild to Moderate Symptoms of COVID-19-Results From a Pilot Open-Label, Randomized Controlled Trial
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Dr. Khaled Mahmoud, MBBChCritical Care Medicine, Longevity Science & Editorial Direction Dr. Amr Yasser, PhDCardiometabolic, Musculoskeletal, Gut & Bioavailability Dr. Abdulla Mostafa, PhDCellular Senescence, Neurological, Mitochondrial & Brain-Ageing Biology