Ivermectin, A Reanalysis of the Data
et al., American Journal of Therapeutics,
Updated meta analysis showing no significant change if Elgazzar et al. is excluded.
Currently there are 99 ivermectin for COVID-19 studies
, showing 49% lower mortality [35‑60%]
, 29% lower ventilation [13‑42%]
, 38% lower ICU admission [14‑56%]
, 34% lower hospitalization [20‑45%]
, and 81% fewer cases [71‑87%]
Marik et al., 2 Sep 2021, peer-reviewed, 2 authors.
Abstract: Letters to the Editor
Queen Mary University of London
London, United Kingdom
The authors have no conflicts of interest to declare.
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Ivermectin, A Reanalysis of the Data
To the Editor:
Our article entitled “Review of the Emerging Evidence Demonstrating the Efficacy of Ivermectin in the
Prophylaxis and Treatment of COVID-19” was recently
published in the American Journal of Therapeutics.1 Our
article included randomized and observational trial
meta-analyses on the efficacy of ivermectin for the prophylaxis and treatment of COVID-19. Recently, the
study conducted by Elgazzar et al2 has come under
scrutiny with accusations of scientific misconduct. His
paper was apparently retracted without his knowledge
and without giving him the opportunity to defend these
serious claims. This situation is most unfortunate. While
this issue is being resolved, we decided to redo the
original meta-analyses excluding this study. The summary point estimates were largely unaffected when the
study by Elgazzar et al was removed. The revised forest
plots are provided below (Figures 1–3).
FIGURE 1. Meta-analysis of ivermectin prophylaxis trials in COVID-19. Symbols: Squares indicate treatment effect of an
individual study. Large diamond reflects summary of study design immediately above. Size of each symbol correlates
with the size of the CI around the point estimate of treatment effect with larger sizes indicating a more precise CI. CI,
confidence interval; OBS, observational study; RCT, randomized controlled trial.
American Journal of Therapeutics (2021) 28(5)
Copyright © 2021 Wolters Kluwer Health, Inc. Unauthorized reproduction of this article is prohibited.
Letters to the Editor
FIGURE 2. Meta-analysis of the outcome of time to clinical recovery from controlled trials of ivermectin treatment in COVID19. Symbols: Squares indicate treatment effect of an individual study. Large diamond reflects summary of study design
immediately above. Small diamond indicates sum effect of all trial designs. Size of each symbol correlates with the size of
the CI around the point estimate of treatment effect with larger sizes indicating a more precise CI. CI, confidence interval.
FIGURE 3. Meta-analysis of the..
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