CD24 and COVID-19: In vitro and in vivo experiments have confirmed the safety and efficacy of EXO-CD24, with no drug-related adverse events reported even in a phase Ib/IIa clinical study.249 Furthermore, EXO-CD24 effectively reduces inflammatory markers and cytokines/chemokines in COVID-19 patients, establishing EXO-CD24 as a potential therapeutic strategy for inhibiting excessive lung inflammation in COVID-19 patients.