|
LETTER TO THE EDITOR| VOLUME 99, P75-76, OCTOBER 2020 Effectiveness of hydroxychloroquine in COVID-19 disease: A done and dusted deal? https://www.ijidonline.com/article/S1201-9712(20)30600-7/fulltext Antonella d’Arminio Monforte; Alessandro Tavelli; Francesca Bai; Giulia Marchetti; Alessandro Cozzi-Lepri Open Access Published: July 29, 2020 Dear Sir, Arshad et al. show evidence for reduced mortality in COVID-19 patients taking hydroxychloroquine alone or with azithromycin in an observational study in the USA ( ). Data on the effectiveness and toxicity of hydroxychloroquine are controversial ( , , , , ). A total of 539 COVID-19 hospitalized patients were included in our cohort in Milan, from February 24 to May 17, 2020, of whom 174 died in hospital (day 14 probability of death: 29.5% – 95%CI: 25.5–34.0). We divided a subset of our cohort into three groups who started treatment a median of 1 day after admission: those receiving hydroxychloroquine alone ( N?=?197), those receiving hydroxycholoroquine?+?azithromycin ( N?=?94), and those receiving neither (controls) ( N?=?92). Of the latter group, ten started HIV antivirals (boosted-lopinavir or –darunavir), one teicoplanin, twelve immunomodulatory drugs, or corticosteroids, 23 heparin and 46 remained untreated. The percent of death in the three groups was 27%, 23%, and 51%. Mechanical ventilation was used in 4.3% of hydroxychloroquine, 14.2% of hydroxychloroquine?+?azithromycin, and 26.1% of controls. Unweighted and weighted relative hazards of mortality are shown in Table 1. After adjusting for several key confounders (see table), the use of hydroxycholoroquine?+?azithromycin was associated with a 66% reduction in risk of death as compared to controls; the analysis also suggested more substantial effectiveness of hydroxychloroquine in patients with less severe COVID-19 disease (PO2/FiO2?>?300, interaction p-value <0.0001). Our results are remarkably similar to those shown by Arshad et al. Table 1Unadjusted and adjusted marginal relative hazards of in-hospital mortality Some important weaknesses in Arshad et al.’s analysis have been pointed out ( ), but not all of these apply to our study. Our propensity scores include some of the potential confounders that were missing in the analysis by Arshad (e.g., calendar day of admission, disease severity, cardiovascular disease (CVD), baseline plasma CRP); second, we have excluded people receiving other drugs which could have biased the effect of hydroxychloroquine when used in combination. Third, although residual confounding is a possibility (e.g., people with CVD were more frequent in control), people in the control group were more likely to undergo mechanical ventilation, which is a conservative bias. These results from two different real-life settings (Italy and USA), conflict with those of two large randomized trials ( , ). Although unmeasured confounding remains the most likely explanation for the discrepancies, a robust meta-analysis is still lacking, and we believe that hydroxychloroquine should be further tested in randomised trials. When best to start treatment is also a question that needs to be addressed in ad-hoc randomized studies. Declarations of interestNone declared. Ethical approvalThis analysis is part of the study approved by Ethic Committee Area 1, Milan Italy (2020/ST/049 and 2020/ST/049_BIS, 11/03/2020). References -
- Arshad S.
- Kigore P.
- Chaudhry Z.S.
- Jacobsen G.
- Wang D.D.
- Huitsing K.
- et al.
Treatment with hydroxychloroquine, azithromycin, and combination in patients hospitalised with COVID-19. Int J Infect Dis. 2020;https://doi.org/10.1016/j.ijid.2020.06.09 -
- Devaux C.A.
- Rolain J.M.
- Colson P.
- Raoult D.
New insights on the antiviral effects of chloroquine against coronavirus: what to expect for COVID-19?. Int J Antimicrob Agents. 2020; ()https://doi.org/10.1016/j.antimicag. 2020.105938 -
- Gautret F.
- Lagier J.C.
- Parola P.
- Hoang V.T.
- Meddeb L.
- Mailhe M.
- et al.
Hydroxychloroquine and azithromycin as a treatment of COVID-19: results of an open-label non-randomised clinical trial. Int J Antimicrob Agents. 2020; ()https://doi.org/10.1016/j.antimicag. 2020.105949 -
- Geleris J.
- Sun Y.
- Platt J.
- Zucker J.
- Baldwin M.
- Hripcsak G.
- et al.
Observational study on hydroxychloroquine in hospitalized patients with COVID-19. N Engl J Med. 2020; 382: 2411-2418https://doi.org/10.1056/NEJMoa2012410 -
- Horby P.
- Lim W.S.
- Emberson J.
- Mafham M.
- Bell J.L.
- Linsell L.
- et al.
Effect of desamethasone in hospitalized patients with CVID-19: preliminary report. COVID-19 SARS-CoV-2 preprints from medRxiv and bioRxiv. 2020 -
- Lee T.C.
- MacKenzie L.J.
- McDonald E.G.
- Tong S.Y.C.
An observational cohort study of hydroxychloroquine and azithromycin for COVID-19: (Can’t get no) satisfaction. Int J Infect Dis. 2020;https://doi.org/10.1016/j.ijid.2020.06.095 -
- Liu J.
- Cao R.
- Xu M.
- Wang X.
- Zhang H.
- Hu H.
- et al.
Hydroxychloroquine, a less toxic derivative of chloroquine, is effective in inhibiting SARS-CoV-2 infection in vitro. Cell Discov. 2020; 6: 16 -
- Tang W.
- Cao Z.
- Han M.
- Wang Z.
- Chen J.
- Sun W.
- et al.
Hydroxychloroquine in patients mainly with mild to moderate COVID-19: an open-label, randomised, controlled trial. BMJ. 2020; 369: m1849https://doi.org/10.1136/bmj.m1849 -
- World Health Organization
“Solidarity” clinical trial for COVID-19 treatments – update on hydroxychloroquine. 2020 () Article infoPublication historyPublished online: July 29, 2020 Received: July 10, 2020 Copyright© 2020 The Author(s). Published by Elsevier Ltd on behalf of International Society for Infectious Diseases. v |
|