Efficacy of SARS-CoV-2 vaccination in patients with monoclonal gammopathies: A cross sectional study

SARS-CoV-2 vaccination is the most effective strategy to protect individuals with haematologic malignancies against severe COVID-19, while eliciting limited vaccine responses. We characterized the humoral responses following 3 mo after mRNA-based vaccines in individuals at different plasma-cell disease stages: monoclonal gammopathy of undetermined significance (MGUS), smoldering multiple myeloma (SMM), and multiple myeloma on first-line therapy (MM), compared with a healthy population. Plasma samples from uninfected MM patients showed lower SARS-CoV-2-specific antibody levels and neutralization capacity compared with MGUS, SMM, and healthy individuals. Importantly, COVID-19 recovered MM individuals presented significantly higher plasma neutralization capacity compared with their uninfected counterparts, highlighting that hybrid immunity elicit stronger immunity even in this immunocompromised population. No differences in the vaccine-induced humoral responses were observed between uninfected MGUS, SMM and healthy individuals. In conclusion, MGUS and SMM patients could be SARS-CoV-2 vaccinated following the vaccine recommendations for the general population, whereas a tailored monitoring of the vaccine-induced immune responses should be considered in uninfected MM patients.This work was partially funded by Grifols, the Departament de Salut of the Generalitat de Catalunya (grant DSL0016 to J Blanco and Grant DSL015 to J Carrillo), the Spanish Health Institute Carlos III (Grant PI17/01518 and PI20/00093 to J Blanco and PI18/01332 to J Carrillo), Fundació Gloria Soler, and the crowdfunding initiatives https://www.yomecorono.com, BonPreu/Esclat and Correos. M Trigueros was supported by a doctoral fellowship from the Departament de Salut from Generalitat de Catalunya (SLT017/20/000095). F Muñoz-Lopez is supported by a doctoral grant from Sorigué Foundation. E Pradenas was supported by a doctoral grant from ANID, Chile: Grant 72180406. M Massanella was granted with RYC2020-028934-I/AEI/10.13039/501100011033 from Spanish Ministry of Science and Innovation and State Research Agency, MCIN/AEI/10.13039/501100011033 and the European Social Fund “investing in your future.