Inhibitors of the mTOR pathway like sirolimus combined with oseltamivir have shown inconsistent effects in murine models of severe influenza [32, 33]. Sirolimus also can modulate inflammatory responses through its immunosuppressive properties [34]. In a small RCT (n = 28), treatment with sirolimus compared to no sirolimus in patients with influenza A(H1N1) pneumonia receiving invasive mechanical ventilation (in addition to oseltamivir and corticosteroids) resulted in improvement in hypoxia, multiple organ dysfunction and virus clearance, and in shorter duration of mechanical ventilation [34]. Further study of sirolimus without systemic corticosteroids is planned among patients hospitalized with influenza (NCT03901001).