Cytokine storm syndrome remains a treatment challenge
“Many who die from COVID-19 suffer hyperinflammation with features of cytokine storm syndrome (CSS) and associated acute respiratory distress syndrome,” wrote Randy Q. Cron, MD, and W. Winn Chatham, MD, of the University of Alabama at Birmingham, and Roberto Caricchio, MD, of Temple University, Philadelphia, in an accompanying editorial. They noted that the SAVE-MORE trial results contrast with another recent randomized trial of canakinumab, which failed to show notable benefits, compared with placebo, in treating hospitalized patients with COVID-19 pneumonia.
“There are some key differences between these trials, one being that anakinra blocks signaling of both IL-1 alpha and IL-1 beta, whereas canakinumab binds only IL-1 beta,” the editorialists explained. “SARS-CoV-2–infected endothelium may be a particularly important source of IL-1 alpha that is not targeted by canakinumab,” they noted.
Additional studies have examined IL-6 inhibition to treat COVID-19 patients, but data have been inconsistent, the editorialists said.
“One thing that is clearly emerging from this pandemic is that the CSS associated with COVID-19 is relatively unique, with only modestly elevated levels of IL-6, CRP, and ferritin, for example,” they noted. However, the SAVE-MORE study suggests that more targeted approaches, such as anakinra, “may allow earlier introduction of anticytokine treatment” and support the use of IL-1 blockade with anakinra for cases of severe COVID-19 pneumonia.
Predicting risk for severe disease
“One of the major challenges in the management of patients with COVID-19 is identifying patients at risk of severe disease who would warrant early intervention with anti-inflammatory therapy,” said Salim Hayek, MD, medical director of the University of Michigan’s Frankel Cardiovascular Center Clinics, in an interview. “We and others had found that soluble urokinase plasminogen activator receptor (suPAR) levels are the strongest predictor of severe disease amongst biomarkers of inflammation,” he said. “In this study, patients with high suPAR levels derived benefit from anakinra, compared to those with placebo. This study is a great example of how suPAR levels could be used to identify high-risk patients that would benefit from therapies targeting inflammation,” Dr. Hayek emphasized.
“The findings are in line with the hypothesis that patients with the highest degrees of inflammation would benefit the best from targeting the hyperinflammatory cascade using anakinra or other interleukin antagonists,” Dr. Hayek said. “Given suPAR levels are the best predictors of high-risk disease, it is not surprising to see that patients with high levels benefit from targeting inflammation,” he noted.
The take-home message for clinicians at this time is that anakinra effectively improves outcomes in COVID-19 patients with high suPAR levels, Dr. Hayek said. “SuPAR can be measured easily at the point of care. Thus, a targeted strategy using suPAR to identify patients who would benefit from anakinra appears to be viable,” he explained.
However, “Whether anakinra is effective in patients with lower suPAR levels (<6 ng/mL) is unclear and was not answered by this study,” he said. “We eagerly await results of other trials to make that determination. Whether suPAR levels can also help guide the use of other therapies for COVID-19 should be explored and would enhance the personalization of treatment for COVID-19 according to the underlying inflammatory state,” he added.
The SAVE-MORE study was funded by the Hellenic Institute for the Study of Sepsis and Sobi, which manufactures anakinra. Some of the study authors reported financial relationships with Sobi and other pharmaceutical companies.
Dr. Cron disclosed serving as a consultant to Sobi, Novartis, Pfizer, and Sironax. Dr. Cron and Dr. Chatham disclosed having received grant support from Sobi for investigator-initiated clinical trials, and Dr. Caricchio disclosed serving as a consultant to GlaxoSmithKline, Johnson & Johnson, Aurinia, and Bristol-Myers Squibb. Dr. Hayek had no relevant financial conflicts to disclose.