JAMA has published a meta-analysis of 15 studies of hospitalized patients with COVID-19 treated with tocilizumab and corticosteroids, showing that a clinically meaningful mortality benefit from tocilizumab (and steroids) was best seen in those not requiring invasive mechanical ventilation (IMV).
The meta-analysis included 15 randomized clinical trials comprising 5339 hospitalized patients with COVID-19 treated with tocilizumab and corticosteroids (in 2020 and 2021), those receiving simple oxygen only or noninvasive ventilation. They used bayesian methods to assess the magnitude of mortality benefit associated with tocilizumab and the differences between respiratory support subgroups in hospitalized COVID-19 patients. The primary outcome measure was all-cause mortality at 28 days after randomization.
What was the effect of oxygen?
From a total of 5339 hospitalized COVID-19 patients, 2117 received simple oxygen only, 2505 received noninvasive ventilation (NIV), and 717 received invasive mechanical ventilation. The overall odds ratios (ORs) for survival were:
- Simple Oxygen: OR 0.70; 0.50-0.91
- NIV: OR 0.81; 0.63-1.03
- IMV: OR 0.89; 0.61-1.22
The probabilities of a survival benefit (OR <1) was better in patients receiving simple oxygen only (98.9%), over NIV (95.5%), and IMV (75.4%).
Tocilizumab superiority in the simple oxygen only subgroup compared with the NIV and IMV subgroups were 85% and 90%.
More research is needed to define which patients will benefit most from tocilizumab and different levels of oxygenation.