{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"institution":[{"name":"bioRxiv"}],"indexed":{"date-parts":[[2026,6,25]],"date-time":"2026-06-25T19:47:24Z","timestamp":1782416844968,"version":"3.54.5"},"posted":{"date-parts":[[2026,6,23]]},"group-title":"Immunology","reference-count":46,"publisher":"openRxiv","license":[{"start":{"date-parts":[[2026,6,23]],"date-time":"2026-06-23T00:00:00Z","timestamp":1782172800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/www.biorxiv.org\/about\/FAQ#license"}],"funder":[{"DOI":"10.13039\/100000002","name":"National Institutes of Health","doi-asserted-by":"crossref","award":["R01 AI 138801"],"award-info":[{"award-number":["R01 AI 138801"]}],"id":[{"id":"10.13039\/100000002","id-type":"DOI","asserted-by":"crossref"}]},{"DOI":"10.13039\/100020366","name":"Massachusetts Consortium on Pathogen Readiness","doi-asserted-by":"crossref","id":[{"id":"10.13039\/100020366","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"accepted":{"date-parts":[[2026,6,23]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                <jats:sec>\n                  <jats:title>Background<\/jats:title>\n                  <jats:p>Nirmatrelvir-ritonavir (N-R) reduces morbidity and mortality from COVID-19 in high-risk individuals; however, N-R use has been associated with risk of SARS-CoV-2 virologic rebound. The mechanisms contributing to virologic rebound after N-R treatment are currently unknown. One plausible mechanism is that antiviral treatment may alter the development of immune responses to SARS-CoV-2 infection, thereby contributing to rebound after cessation of therapy.<\/jats:p>\n                <\/jats:sec>\n                <jats:sec>\n                  <jats:title>Methods<\/jats:title>\n                  <jats:p>We profiled immune responses in a case-ascertained, longitudinal, prospective cohort of ambulatory individuals with COVID-19. Participants were grouped according to whether virological rebound occurred and whether they had received N-R treatment. We assessed antibody, T-cell, and innate responses.<\/jats:p>\n                <\/jats:sec>\n                <jats:sec>\n                  <jats:title>Results<\/jats:title>\n                  <jats:p>We observed no differences in the binding or neutralizing antibody, T-cell, and innate immune responses between participants with virologic rebound compared to participants without virologic rebound. N-R use was associated with slightly weaker antibody responses overall, even after adjustment for immunosuppression.<\/jats:p>\n                <\/jats:sec>\n                <jats:sec>\n                  <jats:title>Conclusion<\/jats:title>\n                  <jats:p>Virologic rebound after N-R treatment is likely driven by non-immune mechanisms.<\/jats:p>\n                <\/jats:sec>\n                <jats:sec>\n                  <jats:title>Funding<\/jats:title>\n                  <jats:p>The project was supported by the National Institutes of Health (R01 AI 138801) and the Massachusetts Consortium on Pathogen Readiness. Its contents are solely the responsibility of the authors and do not necessarily represent the official views of the NIH.<\/jats:p>\n                <\/jats:sec>","DOI":"10.64898\/2026.06.22.733737","type":"posted-content","created":{"date-parts":[[2026,6,24]],"date-time":"2026-06-24T03:35:11Z","timestamp":1782272111000},"source":"Crossref","is-referenced-by-count":0,"title":["Post-infection immune response in adults with COVID-19 with and without nirmatrelvir-ritonavir treatment and virologic rebound"],"prefix":"10.64898","author":[{"given":"Dibya","family":"Ghimire","sequence":"first","affiliation":[{"name":"Massachusetts General Hospital, Boston, Massachusetts"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chloe M.","family":"Hasund","sequence":"additional","affiliation":[{"name":"Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Boston, MA, USA"},{"name":"Infectious Disease and Microbiome Program, Broad Institute, Cambridge, MA, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"John Bianchi","family":"Colangeli","sequence":"additional","affiliation":[{"name":"Massachusetts General Hospital, Boston, Massachusetts"},{"name":"Broad Institute, Cambridge, Massachusetts"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"May Y.","family":"Liew","sequence":"additional","affiliation":[{"name":"Massachusetts General Hospital, Boston, Massachusetts"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Emory","family":"Abar","sequence":"additional","affiliation":[{"name":"Massachusetts General Hospital, Boston, Massachusetts"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mamadou","family":"Barry","sequence":"additional","affiliation":[{"name":"Massachusetts General Hospital, Boston, Massachusetts"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andrew","family":"Alexandrescu","sequence":"additional","affiliation":[{"name":"Massachusetts General Hospital, Boston, Massachusetts"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Benjamin L.","family":"Kotzen","sequence":"additional","affiliation":[{"name":"Massachusetts General Hospital, Boston, Massachusetts"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zahra","family":"Reynolds","sequence":"additional","affiliation":[{"name":"Massachusetts General Hospital, Boston, Massachusetts"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Eliza","family":"Passell","sequence":"additional","affiliation":[{"name":"Massachusetts General Hospital, Boston, Massachusetts"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chase","family":"Mandell","sequence":"additional","affiliation":[{"name":"Massachusetts General Hospital, Boston, Massachusetts"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zoie","family":"Smith-Sparks","sequence":"additional","affiliation":[{"name":"Massachusetts General Hospital, Boston, Massachusetts"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Karry","family":"Su","sequence":"additional","affiliation":[{"name":"Massachusetts General Hospital, Boston, Massachusetts"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Julie","family":"Boucau","sequence":"additional","affiliation":[{"name":"Ragon Institute of Mass General Brigham, MIT, and Harvard, Cambridge, Massachusetts"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Owen T.","family":"Glover","sequence":"additional","affiliation":[{"name":"Ragon Institute of Mass General Brigham, MIT, and Harvard, Cambridge, Massachusetts"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Brooke","family":"Leeman","sequence":"additional","affiliation":[{"name":"Brigham and Women\u2019s Hospital, Boston, Massachusetts"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gregory E.","family":"Edelstein","sequence":"additional","affiliation":[{"name":"Brigham and Women\u2019s Hospital, Boston, Massachusetts"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Manish C.","family":"Choudhary","sequence":"additional","affiliation":[{"name":"Brigham and Women\u2019s Hospital, Boston, Massachusetts"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5300-0571","authenticated-orcid":false,"given":"Yijia","family":"Li","sequence":"additional","affiliation":[{"name":"Brigham and Women\u2019s Hospital, Boston, Massachusetts"},{"name":"University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Naomi","family":"Patel","sequence":"additional","affiliation":[{"name":"Massachusetts General Hospital, Boston, 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