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Bamlanivimab therapy for acute COVID-19 does not blunt SARS-CoV-2–specific memory T cell responses
Sydney I. Ramirez, Alba Grifoni, Daniela Weiskopf, Urvi M. Parikh, Amy Heaps, Farhoud Faraji, Scott F. Sieg, Justin Ritz, Carlee Moser, Joseph J. Eron, Judith S. Currier, Paul Klekotka, Alessandro Sette, David A. Wohl, Eric S. Daar, Michael D. Hughes, Kara W. Chew, Davey M. Smith, Shane Crotty, for the Accelerating COVID-19 Therapeutic Interventions and Vaccines–2/A5401 (ACTIV-2/A5401) Study Team
Sydney I. Ramirez, Alba Grifoni, Daniela Weiskopf, Urvi M. Parikh, Amy Heaps, Farhoud Faraji, Scott F. Sieg, Justin Ritz, Carlee Moser, Joseph J. Eron, Judith S. Currier, Paul Klekotka, Alessandro Sette, David A. Wohl, Eric S. Daar, Michael D. Hughes, Kara W. Chew, Davey M. Smith, Shane Crotty, for the Accelerating COVID-19 Therapeutic Interventions and Vaccines–2/A5401 (ACTIV-2/A5401) Study Team
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Research Article COVID-19 Immunology

Bamlanivimab therapy for acute COVID-19 does not blunt SARS-CoV-2–specific memory T cell responses

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Abstract

Despite the widespread use of SARS-CoV-2–specific monoclonal antibody (mAb) therapy for the treatment of acute COVID-19, the impact of this therapy on the development of SARS-CoV-2–specific T cell responses has been unknown, resulting in uncertainty as to whether anti–SARS-CoV-2 mAb administration may result in failure to generate immune memory. Alternatively, it has been suggested that SARS-CoV-2–specific mAb may enhance adaptive immunity to SARS-CoV-2 via a “vaccinal effect.” Bamlanivimab (Eli Lilly and Company) is a recombinant human IgG1 that was granted FDA emergency use authorization for the treatment of mild to moderate COVID-19 in those at high risk for progression to severe disease. Here, we compared SARS-CoV-2–specific CD4+ and CD8+ T cell responses of 95 individuals from the ACTIV-2/A5401 clinical trial 28 days after treatment with bamlanivimab versus placebo. SARS-CoV-2–specific T cell responses were evaluated using activation-induced marker assays in conjunction with intracellular cytokine staining. We demonstrate that most individuals with acute COVID-19 developed SARS-CoV-2–specific T cell responses. Overall, our findings suggest that the quantity and quality of SARS-CoV-2–specific T cell memory were not diminished in individuals who received bamlanivimab for acute COVID-19. Receipt of bamlanivimab during acute COVID-19 neither diminished nor enhanced SARS-CoV-2–specific cellular immunity.

Authors

Sydney I. Ramirez, Alba Grifoni, Daniela Weiskopf, Urvi M. Parikh, Amy Heaps, Farhoud Faraji, Scott F. Sieg, Justin Ritz, Carlee Moser, Joseph J. Eron, Judith S. Currier, Paul Klekotka, Alessandro Sette, David A. Wohl, Eric S. Daar, Michael D. Hughes, Kara W. Chew, Davey M. Smith, Shane Crotty, for the Accelerating COVID-19 Therapeutic Interventions and Vaccines–2/A5401 (ACTIV-2/A5401) Study Team

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Figure 4

SARS-CoV-2–specific CD4+ memory T cell subsets are equivalent following receipt of mAb or placebo.

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SARS-CoV-2–specific CD4+ memory T cell subsets are equivalent following ...
(A and C) Representative flow cytometry plots of total circulating naive and memory CD4+ T cell subsets (black dots) and proportion of naive/memory cells that are SARS-CoV-2–specific CD4+ T cells by AIM (teal overlay; OX40+41BB+ in A, OX40+CD40L+ in C; see Supplemental Figure 1 for ancestral gating). (B and D) Percentage of SARS-CoV-2–specific CD4+ T cells that are Tcm, Tem, and Temra at study day 28 in individuals who received mAb (3 shades of teal/green circles) or placebo control (3 shades of gray circles) for acute COVID-19 by AIM (B, OX40+41BB and D, OX40+CD40L+) following 24-hour stimulation with SARS-CoV-2 spike or CD4-RE MPs. T cell subtype (Tcm, Tem, and Temra) was assigned based on surface expression of CCR7 and/or CD45RA, as in A and C. Bars represent geometric mean with geometric standard deviation. Equivalent memory T cell populations for treatment and placebo groups were compared by Kruskal-Wallis tests with Dunn’s post hoc correction for multiple comparisons.

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