Summary:
Background: There is an urgent need to improve health outcomes among
severe COVID-19 patients. Therefore, this study aimed to demystify
efficacy and safety of tocilizumab among those patients based on the
best available evidence.
Methods: Nine electronic databases were searched for relevant studies by
three authors in July using search terms ”tocilizumab”, ”COVID”, ”SARS”.
The last date checked was 26 August, 2020. Eligible studies were
assessed through an inclusion criterion focused on cohort studies and
severe COVID-19 adult patients. Any disagreement between the authors was
resolved by discussions. Primary outcomes were mortality and clinical
improvement, while secondary outcomes were tocilizumab-related adverse
effects.
Results: Tocilizumab reduced the mortality rate by 41%, 40%, 28%, and
37% in 7, 14, 21, and 28 days. There was neither statistically
significant difference between the tocilizumab group and the control
group in the clinical improvement (pooled risk ratio1.21 [0.89,
1.64]) nor in respiratory support change. There were no difference
between the two groups in the occurrence of serious adverse events
(pooled risk difference 0.00 [-0.02, 0.03]), bacteremia (pooled risk
ratio 1.25 [0.80, 1.97]), elevation of liver functions (pooled risk
difference -0.00 [-0.03, 0.02]) and infusion related reactions
(pooled risk difference 0.01 [-0.02, 0.03]). However, the occurrence
of neutropenia (pooled risk ratio 9.23 [1.06, 80.24]) and new
infections (pooled risk difference 0.07 [0.00, 0.14]) were more
likely in the tocilizumab group.
Conclusion: Because of the reported adverse effects of tocilizumab in
treating severe COVID-19 patients, the use of that biological agent
should be limited to selected patients based on the best available
evidence.
Key Words : Tocilizumab; COVID-19; SARS COV 2; Systematic
Review; Meta-Analysis; Cohort studies