COVID-19's high mortality may be driven by hyperinflammation. Interleukin-6 (IL-6) axis therapies may reduce COVID-19 mortality. Retrospective analyses of tocilizumab in severe to critical COVID-19 patients have demonstrated survival advantage and lower likelihood of requiring invasive ventilation following tocilizumab administration. The majority of patients have rapid resolution (i.e., within 24-72 hours following administration) of both clinical and biochemical signs (fever and CRP, respectively) of hyperinflammation with only a single tocilizumab dose.~The investigators hypothesized that a dose of tocilizumab significantly lower than the EMA- and FDA-labeled dose (8mg/kg) as well as the emerging standard of care dose (400mg) may be effective in patients with COVID-19 pneumonitis and hyperinflammation. Advantages to the lower dose of tocilizumab may include lower likelihood of secondary bacterial infections as well as extension of this drug's limited supply. The investigators conducted an adaptive single-arm phase 2 trial (NCT04331795) evaluating clinical and biochemical response to low-dose tocilizumab in patients with COVID-19 pneumonitis and hyperinflammation.~This multi-center, prospective, randomized controlled phase 2 trial -- designed as two sub-studies to allow for the possible emergence of data demonstrating the clinical efficacy of tocilizumab 8mg/kg or 400mg -- formally tests the clinical efficacy of low-dose tocilizumab in COVID-19 pneumonia.~Sub-Study A Primary Objective A: To establish whether low-dose tocilizumab reduces the time to clinical recovery in patients with COVID-19 pneumonitis and hyperinflammation, when compared to a tocilizumab-free standard of care.~Hypothesis A: The investigators hypothesize that low-dose tocilizumab, when compared to a tocilizumab-free standard of care, decreases the time to recovery in hospitalized, non-invasively ventilated patients with COVID-19 pneumonitis and hyperinflammation by three days or more.~Sub-Study B Primary Objective B: To establish whether low-dose tocilizumab is near-equivalent to high-dose tocilizumab (400mg or 8 mg/kg) in reducing the time to clinical recovery in patients with COVID-19 pneumonitis and hyperinflammation.~Hypothesis B: The investigators hypothesize that low-dose tocilizumab is near-equivalent to high-dose tocilizumab in reducing the time to clinical recovery in hospitalized, non-invasively ventilated patients with COVID-19 pneumonitis and hyperinflammation.
Tocilizumab is an effective treatment for severe coronavirus disease 2019 (Covid-19) pneumonia and related inflammation. Given limited global supplies, clarification of the optimal tocilizumab dose is critical. We conducted an open-label, randomized, controlled trial evaluating two different dose levels of tocilizumab in Covid-19 (40mg and 120mg). Randomization was stratified on remdesivir and corticosteroid at enrollment. The primary outcome was the time to recovery. The key secondary outcome was 28-day mortality.