Convalescent Plasma does not improve in-hospital mortality among low SARS-CoV-2-IgG antibodies in COVID-19 hospitalized patients

Abstract

Background: The use of convalescent plasma (CP) is recommended as an Emergency Use Authorization (EUA) in the USA for patients with COVID-19. However, limited data are available regarding the impact of this. Our aim was to assess the impact on in-hospital mortality after CP administration according to pre-transfusion antibodies in COVID-19 recipients hospitalized with severe COVID-19 infection. Our hypothesis was that patients with low SARS-CoV-2 IgG antibodies are more likely to benefit with the administration of CP.

Methods: In this observational cohort study, we enrolled consecutive COVID-19 hospitalized patients presenting with COVID-19 disease >18 years of age. CP was administered after obtaining informed consent as part of standard of care. Prior to the administration of CP, the patient had a blood sample drawn for SARS-CoV-2 IgG (Abbott Laboratories – FDA’s EUA – cut off value: more or equal to 1.4 = Positive). Primary outcome was in-hospital mortality.

Results: Among 205 hospitalized patients that received CP for COVID-19, 55 (27%) had SARS-CoV-2 antibodies measured before CP administration. The patient median age was 69 years old (interquartile range [IQR] 60-76) and the majority were men (91%). Low SARS-CoV-2 IgG (<1.4 UI) was identified in 33% of the patients. When comparing low SARS-CoV-2 IgG <1.4 UI vs. low SARS-CoV-2 IgG >1.4 UI, in-hospital mortality was 28% (5/18 patients) compared to 22% (8/37 patients) with an Odds ratio of 0.72 (95% confidence interval 0.20-2.62; p= 0.6), respectively.

Conclusion: The administration of CP did not change in-hospital mortality among patients with high or low SARS-CoV-2 IgG antibodies.