Quercetin as a possible complementary agent for early-stage COVID-19: Concluding results of a randomized clinical trial
Francesco Di Pierro, Amjad Khan, Somia Iqtadar, Sami Ullah Mumtaz, Muhammad Nabeel Akbar Chaudhry, Alexander Bertuccioli, Giuseppe Derosa, Pamela Maffioli, Stefano Togni, Antonella Riva, Pietro Allegrini, Martino Recchia, Nicola Zerbinati
Frontiers in Pharmacology, doi:10.3389/fphar.2022.1096853
Background: Quercetin, a natural polyphenol with demonstrated broadspectrum antiviral, anti-inflammatory, and antioxidant properties, has been proposed as an adjuvant for early-stage coronavirus disease 2019 (COVID-19) infection. Objective: To explore the possible therapeutic effect of quercetin in outpatients with early-stage mild to moderate symptoms of COVID-19.
Methods: This was an open-label randomized controlled clinical trial conducted at the department of medicine, King Edward Medical University, Lahore, PK. Patients were randomized to receive either standard of care (SC) plus an oral quercetin supplement (500 mg Quercetin Phytosome ® , 1st week, TDS: 2nd week, BDS) (n = 50, quercetin group) or SC alone (n = 50, control group). Results: After one week of treatment, patients in the quercetin group showed a speedy recovery from COVID-19 as compared to the control group, i.e., 34 patients (vs. 12 in the control group) tested negative for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) (p = 0.0004), and 26 patients (vs. 12 in the control group) had their COVID-19-associated acute symptoms resolved (p = 0.0051). Patients in the quercetin group also showed a significant fall in the serum lactate dehydrogenase (LDH) mean values i.e., from 406.56 ± 183.92 to 257.74 ± 110.73 U/L, p = 0.0001. Quercetin was well-tolerated by all the 50 patients, and no side effects were reported.
Ethics statement The study was approved by the Institutional Review Board, King Edward Medical University, Lahore, Pakistan via Ref. No. 192 /RC/KEMU. The patients/participants provided their written informed consent to participate in this study.
Author contributions
Conflict of interest FDP belongs to the Scientific Board of Pharmextracta. AB is a Pharmextracta scientific advisor. ST, PA, and AR belong to the Scientific Board of Indena. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.
Publisher's note All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.
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