Blockade of IL-33 with itepekimab, compared to placebo, was shown to reduce exacerbations in patients with moderate-to-severe asthma when treatment with steroids was withdrawn [147], and blockade of ST2 with astegolimab reduced the annualized asthma exacerbation rate in a broad population of severe asthma patients, including those defined as eosinophil-low [148]. This evidence concerns the gene IL1RL1 and asthma.