Anti-IL-9 (eg, MEDI-528) IL-9 ILC2, γδT17 cells, effector memory T cells, neutrophils, mast cells, M2 macrophages Might inhibit expansion of lymphoid cells, mast cell activation, and neutrophil recruitment in COVID-19 pneumonia; and might inhibit production of TGFβ and pulmonary fibrosis Might favour proinflammatory activation of monocytes and macrophages