The drugs reduce inflammation and doctors hope they can help patients recover from the overwhelming immune response that sometimes triggers Covid-19.
Patients were randomly assigned to receive infusions of two drugs for rheumatoid arthritis, tocilizumab or sarilumab, or to receive standard treatment at the time, which includes corticosteroids for most patients.
The international team of researchers found that patients who received any of the drugs for rheumatoid arthritis experienced significantly more days when they did not need organ support compared to those who received standard treatment.
The data showed that patients who received tocilizumab had a median of 10 days when they did not need organ support and those who received sarilumab had a median of 11 days. Patients who did not receive any of the drugs had zero days without organ support.
The researchers also found that 27% of patients who received arthritis drugs died in the hospital, compared with 36% of those who received standard treatment.
“We also saw patients recover more quickly,” he said. “They were improving and could be discharged from the ICU faster – and that was normal and each patient is a little different.”
Some serious adverse events were reported during the study. Nine were among those who received tocilizumab, including a bacterial infection, five bleeding events, two cardiac events and one person with impaired vision. Eleven adverse events were among those receiving standard treatment, including four bleeding events and seven cases of blood clotting. No serious adverse events were reported among those who received sarilumab.
Although the new study suggests that treatment with tocilizumab and sarilumab may improve outcomes for patients critically with Covid-19, the researchers noted that some separate studies have found no previous benefit with tocilizumab.
“Many previously reported included less severe patients and excluded patients who already received respiratory support,” wrote the researchers in the study. “In these studies, no clear evidence suggested that tocilizumab was effective in preventing disease progression and no benefit regarding survival was seen.”
‘How best to use them remains uncertain’
Among 452 patients who were randomly assigned to receive a single intravenous infusion of tocilizumab or a placebo, the 28-day mortality rate was 19.7% in the tocilizumab group and 19.4% in the placebo group, according to the study summary.
“In this study involving patients hospitalized with severe Covid-19 pneumonia, we found no significant difference in clinical status between the tocilizumab group and the placebo group on day 28. No mortality benefit was associated with the use of tocilizumab, although the study was not fueled for this outcome, “wrote the researchers at Baylor College of Medicine in Houston and several other institutions around the world.
Tocilizumab was well tolerated, the researchers say, and their data suggest that patients may have benefited from the drug, although more research is needed to be sure.
Differences between studies include the severity of the patients’ illness, the time the treatment was administered and the other types of treatment that the patients may have received, such as corticosteroids, Dr. Eric Rubin, editor-in-chief of the New England Journal of Medicine, and its co-authors, Dr. Dan Longo and Dr. Lindsey Baden, wrote in the editorial.
“These points raise thorny questions,” write the authors of the editorial. “For now, we are left with evidence of the benefit of interleukin-6 inhibitors, at least in some circumstances, but the best way to use them remains uncertain.”