Clinical evidence of an interferon-glucocorticoid therapeutic synergy in COVID-19.

Synthetic glucocorticoid dexamethasone is the first trial-proven drug that reduces COVID-19 mortality by suppressing immune system. In contrast, interferons are a crucial component of host antiviral immunity and can be directly suppressed by glucocorticoids. To investigate whether therapeutic interferons can compensate glucocorticoids-induced loss of antiviral immunity, we retrospectively analyzed a cohort of 387 PCR-confirmed COVID-19 patients with quasi-random exposure to interferons and conditional exposure to glucocorticoids. Among patients receiving glucocorticoids, early interferon therapy was associated with earlier hospital discharge (adjusted HR 1.68, 95% CI 1.19-2.37) and symptom relief (adjusted HR 1.48, 95% CI 1.06-2.08), while these associations were insignificant among glucocorticoids nonusers. Early interferon therapy was also associated with lower prevalence of prolonged viral shedding (adjusted OR 0.24, 95% CI 0.10-0.57) only among glucocorticoids users. Additionally, these associations were glucocorticoid cumulative dose- and timing-dependent. These findings reveal potential therapeutic synergy between interferons and glucocorticoids in COVID-19 that warrants further investigation.

Retrospective Multicenter Cohort Study Shows Early Interferon Therapy Is Associated with Favorable Clinical Responses in COVID-19 Patients.

Interferons (IFNs) are widely used in treating coronavirus disease 2019 (COVID-19) patients. However, a recent report of ACE2, the host factor mediating SARS-Cov-2 infection, identifying it as interferon-stimulated raised considerable safety concern. To examine the association between the use and timing of IFN-α2b and clinical outcomes, we analyzed in a retrospective multicenter cohort study of 446 COVID-19 patients in Hubei, China. Regression models estimated that early administration (≤5 days after admission) of IFN-α2b was associated with reduced in-hospital mortality in comparison with no admission of IFN-α2b, whereas late administration of IFN-α2b was associated with increased mortality. Among survivors, early IFN-α2b was not associated with hospital discharge or computed tomography (CT) scan improvement, whereas late IFN-α2b was associated with delayed recovery. Additionally, early IFN-α2b and umifenovir alone or together were associated with reduced mortality and accelerated recovery in comparison with treatment with lopinavir/ritonavir (LPV/r) alone. We concluded that administration of IFN-α2b during the early stage of COVID-19 could induce favorable clinical responses.