Validation of Viral Inactivation Protocols for Therapeutic Blood Products against Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2)

Therapeutic blood products including convalescent plasma/serum and immunoglobulins concentrated from convalescent plasma, such as intravenous immunoglobulins or hyperimmune globulins, and monoclonal antibodies are passive immunotherapy options for novel coronavirus disease 2019 (COVID-19). They have been shown to improve the clinical status and biological and radiological parameters in some groups of COVID-19 patients. However, blood products are still potential sources of virus transmission in recipients. The use of pathogen reduction technology (PRT) should increase the safety of the products. The purpose of this study was to determine the impact of solvent/detergents (S/D) procedures on SARS-CoV-2 infectivity elimination in the plasma of donors but also on COVID-19 convalescent serum (CCS) capacity to neutralize SARS-CoV-2 infectivity. In this investigation, S/D treatment for all experiments was performed at a shortened process time (30 min). We first evaluated the impact of S/D treatments (1% TnBP/1% TritonX-45 and 1% TnBP/1% TritonX-100) on the inactivation of SARS-CoV-2 pseudoparticles (SARS-CoV-2pp)-spiked human plasma followed by S/D agent removal using a Sep-Pak Plus C18 cartridge. Both treatments were able to completely inactivate SARS-CoV-2pp infectivity to an undetectable level. Moreover, the neutralizing activity of CCS against SARS-CoV-2pp was preserved after S/D treatments. Our data suggested that viral inactivation methods using such S/D treatments could be useful in the implementation of viral inactivation/elimination processes of therapeutic blood products against SARS-CoV-2.