“Organizations are encouraged to consider prescribing tocilizumab or sarilumab in the treatment of inpatients in intensive care with Covid-19 pneumonia,” said the new guidance from British health officials. Dr. Gordon noted that this is the strongest official advice issued to date on the immunological drug pair.
Some experts outside Britain are acting more cautiously. Both Dr. Schwartz and Dr. Kaplan-Lewis noted that while the data may be sufficient to persuade the FDA to authorize tocilizumab and sarilumab for emergency use in the United States, the jury has yet to decide on these drugs. And Dr. Boghuma Kabisen Titanji, an infectious disease physician at Emory University, pointed out that only about 4 percent of study volunteers identified as black, which may make the results less applicable to the general population, given the high vulnerability color communities to Covid19.
Further studies are needed to clarify when and in which tocilizumab and sarilumab patients work best, and to uncover why their benefits have clearly emerged in some studies, but not in others, said Dr. Kaplan-Lewis. It is also a challenge to compare the studies that are now coming out with previous tests that were conducted when the virus was much less understood, treatments were administered with less knowledge and mortality rates were even higher.
“If patients got better supportive care, perhaps their results would improve a lot,” said Dr. Krutika Kuppalli, an infectious physician at the University of South Carolina Medical School who was not involved in the study. “Yes, therapy is useful. But it is also about improving the standard of care for people. “
The new study and others suggested that the medication window of opportunity is narrow – within the first day or more after admission to an ICU, said Dr. Kaplan-Lewis. Given too early, the drugs may not cause a measurable reduction in the immune response; delivered too late, and the damage may have already been done. “Maybe that’s when a person has just become critical,” she said.
This tipping point is not always easy to define. Patients enter intensive care in different states, and the limit for critical illnesses may not be uniform across hospitals. And, like all other immunosuppressive drugs, tocilizumab and sarilumab can increase the risk of infection with other viruses or bacteria.
The data is “encouraging,” said Kuppalli. “But I think we need to understand why this data looks different from other studies, before we start implementing this as a generalized policy.”