The study represents the largest clinical series of COVID-19 patients treated with tocilizumab to date. The research examined the first 239 hospitalized COVID-19 patients at YNHH, 153 of whom were treated with tocilizumab.
The team found that COVID-19 patients with CRS who were treated with tocilizumab showed relatively low mortality rates overall compared to reports from other hospitals, especially those CRS patients who required mechanical ventilation—typically a poor prognostic indicator. The 14-day survival rate for all tocilizumab-treated patients, most of whom met admission criteria for severe COVID-19, was 87%. The 48 tocilizumab-treated patients who required mechanical ventilation spent an average of five and a half days on a ventilator, and their 14-day survival rate was 75%.
"Typically, at least half of the patients who require mechanical ventilation die, but in those treated with tocilizumab here, only 25% did," said Dr. Maricar Malinis, one of the senior authors and associate professor of medicine (infectious diseases).
Across studies, mortality rates for COVID-19 patients requiring ventilation ranges from 40% to 90%.
To determine which patients with COVID-19 would receive the drug, the Yale team designed an algorithm to identify patients who appeared to have CRS, as indicated by required oxygen and inflammatory markers.
