Convalescent plasma for patients with multiple myeloma and COVID-19; the European Myeloma Network consensus

Summary: Recent 2022 SARS-CoV-2 Omicron variants show resistance to authorized monoclonal antibodies, particularly the BQ.1.* sublineages. However, polyclonal antibodies from vaccinated or recently recovered individuals retain neutralizing activity against Omicron. A study analyzing patient samples from boosted vaccine cohorts and infection cases found that over 90% of plasma samples neutralized BQ.1.1 and BF.7, with complete neutralization of other variants. Plasma from COVID-19-naive subjects who received a third vaccine dose showed lower neutralization titres compared to VaxCCP. Boosted VaxCCP, either through recent vaccination or infection within 6 months, provides a robust and variant-resilient source of neutralizing antibodies against Omicron BQ.1.1, XBB.1, and BF.7 variants.

Summary: In the post-pandemic COVID-19 period, patients with multiple myeloma (MM) are at increased risk for severe COVID-19 outcomes. The European Myeloma Network recommends vaccination with variant-specific booster vaccines every 6-12 months to overcome the emergence of novel strains. Evaluation of immune response after vaccination can identify vulnerable patients who may need additional boosters and preventive measures. Certain antiviral drugs are effective against specific Omicron subvariants and should be administered in MM patients with positive COVID-19 tests or symptoms.