Mike: Hello, I'm Mike Clarke, podcast editor for the Cochrane Library. Cochrane is producing a growing series of reviews on the care of patients with COVID-19. In January 2022, we published a new review of a group of treatments called interleukin-1 blocking agents and we asked lead author, Mauricia Davidson from Cochrane France, to tell us about the findings.

Mauricia: Interleukin‐1, or IL‐1 for short, is a type of protein called a cytokine, which triggers inflammation to help fight infection. In COVID‐19, as the patient's immune system fights the virus, the lungs and airways become inflamed, causing breathing difficulties. However, in some people, the immune system can overreact, leading to a ‘cytokine storm'. This produces dangerously high levels of inflammation and tissue damage and can cause severe breathing difficulties, organ failure and death.
Interleukin-1 blocking agents, such as anakinra and canakinumab are medicines that stop IL‐1 from working by blocking its signals to other parts of the immune system. This, in turn, reduces inflammation and may help the patient's immune system to fight COVID‐19.
Therefore, in this review, we're investigating whether IL‐1 blockers are effective for people with COVID‐19, when compared with standard care alone or with placebo. In our most recent search on November 5th 2021, we found six multicenter, randomized trials with 2132 participants that we were able to use in the review and 16 trials that had not yet published their results.
Four of the included trials assessed anakinra and the other two assessed canakinumab. On average, participants in the trials were between 58 and 68 years old and most were men. All participants were hospitalized, mainly with moderate to critical COVID‐19 and, at the start of the trials, at least two thirds of participants were receiving oxygen, and at most one third were intubated.
Turning to the results, our findings show that anakinra and canakinumab probably result in little or no clinical improvement in COVID‐19 in the first 28 days after treatment. The data on whether use of these drugs affects the number of deaths are very unreliable and although both anakinra and canakinumab probably don't lead to an important increase in any adverse events, their effect on serious adverse events is unclear.
Put simply, and as the takeaway message for the current version of our review, we did not find evidence for an important beneficial effect of interleukin‐1 blocking agents for patients with COVID-19, and the available evidence is uncertain or very uncertain for several outcomes.

Mike: If you would like to look deeper into this evidence and watch for future updates of the review, it's available online at Cochrane Library dot com. If you go to the website and search 'IL-1 and COVID-19', you'll see a link to it.