Impact of serological and PCR testing requirements on the selection of COVID-19 convalescent plasma donors
BACKGROUND Convalescent plasma is undergoing randomized trials as a potential therapeutic option for COVID-19 infection. Little empirical evidence exists regarding the determination of donor eligibility and experiences with donor selection. STUDY DESIGN AND METHODS This prospective study was conducted at a tertiary care hospital in New York to select plasma donors for a randomized, double-blind, controlled convalescent plasma trial. Clearance for donation required successful completion of an online questionnaire and an in-person screening visit, which included (a) completion of a Donor Health Questionnaire (DHQ), (b) Immunoglobulin G (IgG) antibody testing using an immunochromatographic anti- severe acute respiratory coronavirus 2 (SARS-CoV-2) test, (c) Polymerase chain reaction (PCR) testing if <28 days from symptom resolution, and (d) routine blood bank testing. RESULTS After receiving 3093 online questionnaires, 521 individuals presented for in-person screening visits, with 40.1% (n = 209) fully qualifying. Subjects (n = 312) failed to progress due to the following reasons: disqualifying answer from DHQ (n = 30, 9.6%), insufficient antibodies (n = 198, 63.5%), persistent positive PCR tests (n = 14, 4.5%), and blood donation testing labs (n = 70, 22.4%). Importantly, 24.6% and 11.1% of potential donors who reported having PCR-diagnosed infection had low or undetectable SARS-CoV-2 antibody levels, respectively. Surprisingly, 62.9% (56/89) of subjects had positive PCR tests 14-27 days after symptom resolution, with 13 individuals continuing to be PCR positive after 27 days. CONCLUSION It is feasible for a single site to fully qualify a large number of convalescent plasma donors in a short period of time. Among otherwise qualified convalescent plasma donors, we found high rates of low or undetectable antibody levels and many individuals with persistently positive PCR tests.
Donors for SARS-CoV-2 Convalescent Plasma for a Controlled Clinical Trial: Donor Characteristics, Content and Time Course of SARS-CoV-2 Neutralizing Antibodies
Transfusion Medicine & Hemotherapy. 2021;:1-10
Background: Convalescent plasma is one of the treatment options for COVID-19 which is currently being investigated in many clinical trials Understanding of donor and product characteristics is important for optimization of convalescent plasma Methods: Patients who had recovered from COVID-19 were recruited as donors for COVID-19 convalescent plasma (CCP) for a randomized clinical trial of CCP for treatment of severe COVID-19 (CAPSID Trial) Titers of neutralizing antibodies were measured by a plaque-reduction neutralization test (PRNT) Correlation of antibody titers with host factors and evolution of neutralizing antibody titers over time in repeat donors were analysed Results: A series of 144 donors (41% females, 59% males;median age 40 years) underwent 319 plasmapheresis procedures providing a median collection volume of 850 mL and a mean number of 2 7 therapeutic units per plasmapheresis The majority of donors had a mild or moderate course of COVID-19 The titers of neutralizing antibodies varied greatly between CCP donors (from 1:640) Donor factors (gender, age, ABO type, body weight) did not correlate significantly with the titer of neutralizing antibodies We observed a significant positive correlation of neutralization titers with the number of reported COVID-19 symptoms and with the time from SARS-CoV-2 diagnosis to plasmapheresis Neutralizing antibody levels were stable or increased over time in 58% of repeat CCP donors Mean titers of neutralizing antibodies of first donation and last donation of repeat CCP donors did not differ significantly (1:86 at first compared to 1:87 at the last donation) There was a significant correlation of neutralizing antibodies measured by PRNT and anti-SARS-CoV-2 IgG and IgA antibodies which were measured by ELISA CCP donations with an anti-SARS-CoV-2 IgG antibody content above the 25th percentile were substantially enriched for CCP donations with higher neutralizing antibody levels Conclusion: We demonstrate the feasibility of collection of a large number of CCP products under a harmonized protocol for a randomized clinical trial Titers of neutralizing antibodies were stable or increased over time in a subgroup of repeat donors A history of higher number of COVID-19 symptoms and higher levels of anti-SARS-CoV-2 IgG and IgA antibodies in immunoassays can preselect donations with higher neutralizing capacity [ABSTRACT FROM AUTHOR] Copyright of Transfusion Medicine & Hemotherapy is the property of Karger AG and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission However, users may print, download, or email articles for individual use This abstract may be abridged No warranty is given about the accuracy of the copy Users should refer to the original published version of the material for the full abstract (Copyright applies to all Abstracts )