Safety of Plasmapheresis in Donors with Low IgG Levels: Results of a Prospective, Controlled Multicentre Study.

Background and Objectives: Although plasmapheresis is generally considered safe, there are still concerns about the long-term effects of plasma donation on immunoglobulin G (IgG) levels. The aim of the present study was to investigate if there is a need to permanently defer donors who donated three times with an IgG level below 6.0 g/L. Study Design and Methods: From September 2007 to December 2017, adverse events (AEs) including infections were analysed from data of a prospective, controlled multicentre study of healthy volunteer donors, participating in an individualized plasmapheresis programme stratified by initial IgG level and body weight (individualized arm) or in standard plasmapheresis according to national guidelines (control arm). IgG was monitored at every fifth donation, and donors with IgG levels below the threshold were identified and followed up for possible AEs. Results: In total, 97,540 donations in 1,462 donors in the control arm and 1,491,223 donations in 14,281 donors in the individualized arm were included. Donation-based incidences of at least severe AEs and any infections were 0.019% and 0.192% in the control arm, and 0.014% and 0.153% in the individualized arm. Three or more IgG-measurements below the threshold occurred in 38.2% of control arm donors and 20.9% of individualized arm donors. There were no increased incidence rates of at least severe AEs or any infections in donors with ≥3 IgG-measurements below the threshold in either donor's arm. Conclusions: Our data show no signs of compromised donor safety in donors with ≥3 IgG-measurements below the threshold, indicating that plasmapheresis is feasible and safe in these donors.