Single dose of arthritis drug tocilizumab lowers COVID-19 mortality rate of critically ill patients by 45 per cent

Researchers of a new study say that patients who received intravenous tocilizumab fare much better despite developing additional infections.

By: Jahnavi Sarma | | Published: July 14, 2020 11:57 am

Earlier, in March, during the initial days of the pandemic, tocilizumab was identified as a potentially beneficial therapy for critically ill COVID-19 patients.

According to a new study from the University of Michigan, critically ill COVID-19 patients who received a single dose of tocilizumab intravenously were 45 per cent less likely to die overall. They were also more likely to be out of the hospital or off a ventilator one month after treatment, compared with those who didn’t receive the drug, say researchers. This drug calms ‘cytokine storm’ or an overactive immune system that is caused by COVID-19 infection. The lower risk of death in patients who received intravenous tocilizumab happened despite the fact that they were also twice as likely to develop an additional infection, on top of the novel coronavirus. The study is published in the peer-reviewed journal Clinical Infectious Diseases after being available as a pre-print last month. Also Read - Vaping increases risk of COVID-19 by almost 7 times

Tocilizumab helps patients with ‘superinfections’

To arrive at their conclusions, researchers took a look at data from 154 critically ill patients treated at Michigan Medicine, U-M’s academic medical center, during the first six weeks of the pandemic’s arrival in Michigan from early March to late April. During that time, when little was known about what would help COVID-19 patients on ventilators, about half of the studied patients received the arthritis drug tocilizumab and half did not. Most received it within the 24-hour period surrounding their intubation. Also Read - Will Russia be allowed to conduct trials of its controversial COVID-19 vaccine ‘Sputnik V’ in India?

During the course of the study, researchers saw that by the end of the 28-day period after patients went on a ventilator, 18 per cent of those who received tocilizumab had died, compared with 36 per cent of those who had not. When adjusted for health characteristics, this represents a 45 per cent reduction in mortality. Of those still in the hospital at the end of the study period, 82 per cent of the tocilizumab patients had come off the ventilator, compared with 53 per cent of those who didn’t receive the drug. In all, 54 per cent of the tocilizumab patients developed a secondary infection, mostly ventilator associated pneumonia and 26 per cent of those who didn’t receive tocilizumab developed such infections. Such “superinfections” usually reduce the chance of survival for COVID-19 patients. Also Read - Sputnik V: How Russia's COVID-19 vaccine works and why safety concerns are genuine

Reduced mortality risk despite increase in secondary infections

Initially, researchers were no sure about what they will discover, whether they would find any benefit, a risk, or no clear effect associated with tocilizumab in the patients with life-threatening COVID-19. But they knew it was a critically important question that they were uniquely positioned to answer at that point in the pandemic. But they found that the difference in mortality despite the increase in secondary infection is quite pronounced, even after accounting for many other factors.

Earlier, in March, during the initial days of the pandemic, tocilizumab was identified as a potentially beneficial therapy for critically ill COVID-19 patients. However, experts are concerned about its possible risks and lack of evidence for its use in COVID-19. Many recommended a dose of 8 milligrams per kilogram. Some physicians choose to use it, while others did not.

This drug calms the cytokine storm

The results suggest a benefit from timely and targeted efforts to calm the “cytokine storm” caused by the immune system’s overreaction to the coronavirus. Tocilizumab, originally designed for rheumatoid arthritis, has already been used to calm such storms in patients receiving advanced immunotherapy treatment for cancer.

Tocilizumab better than dexamethasone, say experts

Data released in June from a large randomized controlled trial in the United Kingdom hints that the steroid dexamethasone may be the first choice to treat critically ill COVID-19 patients. According to researchers of the above-mentioned study, due to the lack of randomized controlled trial data and the much higher cost, they would recommend reserving tocilizumab for the treatment of select patients who decompensate while on or after receiving dexamethasone or in patients where the risks of adverse events from steroid therapy outweigh the potential benefits. They admit that further studies of tocilizumab, which is more targeted than dexamethasone in addressing the hyperinflammatory process, could include combining these agents or comparing them head-to-head. They also add that a single dose of tocilizumab is roughly 100 times more expensive than a course of dexamethasone. Another drug that aims to treat cytokine storm by targeting the interleukin-6 (IL-6) receptor, one called sarilumab, appears to have failed to improve outcomes in a clinical trial in COVID-19 patients including those on ventilators.

(With inputs from Agencies)

Published : July 14, 2020 11:57 am

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