SARS-CoV-2 antibody changes in patients receiving COVID-19 convalescent plasma from normal and vaccinated donors

Abstract

Background and Objectives: Vaccination has been shown to stimulate remarkably high antibody levels in donors who have recovered from COVID-19. Our objective was to examine patient antibody responses following COVID-19 Convalescent Plasma (CCP) transfusion and compare responses to CCP from vaccinated and nonvaccinated donors. Materials and methods: Plasma samples were obtained from 25 recipients of CCP and COVID-19 antibody levels measured before and after CCP treatment. Factors that effect antibody levels were examined. Results: In the 21 patients who received CCP from nonvaccinated donors, only modest increases in antibody levels were observed. Patients who received two units were more likely to seroconvert than those receiving just one unit. The strongest predictor of changes in patient antibody level was the CCP dose. Using patient plasma volume and donor antibody level, the post-transfusion antibody level could be predicted with remarkable accuracy. In contrast, the 4 patients who received CCP from vaccinated donors all had dramatic increases in antibody levels following transfusion of a single unit. In this subset of recipients, antibody levels observed after transfusion of CCP were comparable to those seen in donors who had fully recovered from COVID-19. Conclusion: If available, CCP from vaccinated donors with very high antibody levels should be used. CCP from vaccinated donors increases patient antibody levels much more than 1 or 2 units of CCP from unvaccinated donors.

Mortality rates among hospitalized patients with COVID-19 treated with convalescent plasma A Systematic review and meta-analysis

“…In this framework, three matched cohort studies 98,109,114 enrolling 330 participants and 12 case series 54,[134][135][136][137][138][139][140][141][142][143][144] enrolling 29,361 participants were included in this subgroup analysis. In this subgroup meta-analysis, treatment with COVID-19 convalescent plasma containing high antibody levels was associated with a 15% decrease in mortality rates compared to convalescent plasma containing low antibody levels, with a pooled risk ratio estimate of 0.85 (95% CI, 0.73 to 0.99).…”

COVID 19 convalescent plasma: Is there still a place for CCP?

“…The antibody dose can be calculated by multiplying donor’s antibody level by the unit volume. Leon et al found a high correlation between the predicted SARS-CoV-2 antibody level and the actual SARS-CoV-2 antibody level after transfusion [9] .…”

Are convalescent plasma stocks collected during former COVID‐19 waves still effective against current SARS‐CoV‐2 variants?

“…Vax‐CCP is also less likely to benefit from expensive pathogen inactivation technologies since collections do not stem from recently hospitalized subjects, and this makes product manufacturing simpler and cheaper. Transfusion of Vax‐CCP has resulted in recipient nAb titres as high as seen in convalescents [19] and, together with emergence of novel VOCs with Spike mutations, could re‐launch the declining CCP demand over monoclonal antibodies. As more recovered patients are vaccinated, Vax‐CCP may emerge as a source of both high nAb titre and “broad spectrum” CCP during the next phases of the pandemic.…”