Influence of anti-Spike protein antibody levels on tocilizumab efficacy in hospitalized patients with severe COVID-19 pneumonia: a post-hoc analysis of the COVACTA trial

Abstract Background Our aim in this work is to find biomarkers to optimize therapy with IL-6 inhibitors, as not all clinical trials have shown clear benefits on mortality or mechanical ventilation progression. Given the link between delayed seroconversion and higher complication risks, we aim to tes...

Full description

Saved in:
Bibliographic Details
Main Authors: José Aguareles, Carles Forné, Ana García-Casas, Guillermo Santamaría-Corral, Daniel Carnevali-Ruiz, Gabriel Sotres-Fernández, Javier T Solera, Pablo Guisado-Vasco
Format: Article
Language:English
Published: BMC 2025-05-01
Series:BMC Infectious Diseases
Subjects:
Online Access:https://doi.org/10.1186/s12879-025-11001-6
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1850190508249317376
author José Aguareles
Carles Forné
Ana García-Casas
Guillermo Santamaría-Corral
Daniel Carnevali-Ruiz
Gabriel Sotres-Fernández
Javier T Solera
Pablo Guisado-Vasco
author_facet José Aguareles
Carles Forné
Ana García-Casas
Guillermo Santamaría-Corral
Daniel Carnevali-Ruiz
Gabriel Sotres-Fernández
Javier T Solera
Pablo Guisado-Vasco
author_sort José Aguareles
collection DOAJ
description Abstract Background Our aim in this work is to find biomarkers to optimize therapy with IL-6 inhibitors, as not all clinical trials have shown clear benefits on mortality or mechanical ventilation progression. Given the link between delayed seroconversion and higher complication risks, we aim to test if evaluating SARS-CoV-2 spike protein antibody status before treatment could enhance IL-6 inhibitor therapy effectiveness in COVID-19 patients. Methods We conducted a post hoc analysis of the COVACTA study, a phase 3, randomized, double-blind, placebo-controlled trial of the efficacy and safety of tocilizumab in hospitalized patients with severe COVID-19. Cox and logistic regression analysis were used to assess the tocilizumab’s efficacy in severe COVID-19 patients on survival and ICU stay at day 28, based on SARS-CoV-2 S-spike and neutralizing antibody levels. Results Tocilizumab reduced 28-day mortality over placebo in patients with low S-spike antibody titers (20% vs. 29%). No benefit was observed for higher antibody levels. Patients with low S-spike antibody levels treated with tocilizumab exhibited a lower probability of ICU stay at day 28 compared to those treated with placebo (63% vs. 82%). No significant differences were noted in mortality and ICU stay based on whole neutralizing antibody titers. Conclusions Our findings suggest that using IL-6 inhibitors in severe COVID-19 patients with low S-spike antibody titers may improve clinical outcomes. Clinical trial Not applicable.
format Article
id doaj-art-b0468b913e324a149c0c0ef0b5b84366
institution OA Journals
issn 1471-2334
language English
publishDate 2025-05-01
publisher BMC
record_format Article
series BMC Infectious Diseases
spelling doaj-art-b0468b913e324a149c0c0ef0b5b843662025-08-20T02:15:16ZengBMCBMC Infectious Diseases1471-23342025-05-012511910.1186/s12879-025-11001-6Influence of anti-Spike protein antibody levels on tocilizumab efficacy in hospitalized patients with severe COVID-19 pneumonia: a post-hoc analysis of the COVACTA trialJosé Aguareles0Carles Forné1Ana García-Casas2Guillermo Santamaría-Corral3Daniel Carnevali-Ruiz4Gabriel Sotres-Fernández5Javier T Solera6Pablo Guisado-Vasco7Internal Medicine Department, Hospital Universitario Quirónsalud MadridHeorfy ConsultingInternal Medicine Department, Hospital Universitario Quirónsalud MadridInternal Medicine Department, Hospital Universitario Quirónsalud MadridInternal Medicine Department, Hospital Universitario Quirónsalud MadridInternal Medicine Department, Hospital Universitario Quirónsalud MadridInternal Medicine Department, Hospital Universitario Quirónsalud MadridInternal Medicine Department, Hospital Universitario Quirónsalud MadridAbstract Background Our aim in this work is to find biomarkers to optimize therapy with IL-6 inhibitors, as not all clinical trials have shown clear benefits on mortality or mechanical ventilation progression. Given the link between delayed seroconversion and higher complication risks, we aim to test if evaluating SARS-CoV-2 spike protein antibody status before treatment could enhance IL-6 inhibitor therapy effectiveness in COVID-19 patients. Methods We conducted a post hoc analysis of the COVACTA study, a phase 3, randomized, double-blind, placebo-controlled trial of the efficacy and safety of tocilizumab in hospitalized patients with severe COVID-19. Cox and logistic regression analysis were used to assess the tocilizumab’s efficacy in severe COVID-19 patients on survival and ICU stay at day 28, based on SARS-CoV-2 S-spike and neutralizing antibody levels. Results Tocilizumab reduced 28-day mortality over placebo in patients with low S-spike antibody titers (20% vs. 29%). No benefit was observed for higher antibody levels. Patients with low S-spike antibody levels treated with tocilizumab exhibited a lower probability of ICU stay at day 28 compared to those treated with placebo (63% vs. 82%). No significant differences were noted in mortality and ICU stay based on whole neutralizing antibody titers. Conclusions Our findings suggest that using IL-6 inhibitors in severe COVID-19 patients with low S-spike antibody titers may improve clinical outcomes. Clinical trial Not applicable.https://doi.org/10.1186/s12879-025-11001-6TocilizumabSARS-CoV-2COVID-19AntibodiesSerostatusIL-6 inhibitors
spellingShingle José Aguareles
Carles Forné
Ana García-Casas
Guillermo Santamaría-Corral
Daniel Carnevali-Ruiz
Gabriel Sotres-Fernández
Javier T Solera
Pablo Guisado-Vasco
Influence of anti-Spike protein antibody levels on tocilizumab efficacy in hospitalized patients with severe COVID-19 pneumonia: a post-hoc analysis of the COVACTA trial
BMC Infectious Diseases
Tocilizumab
SARS-CoV-2
COVID-19
Antibodies
Serostatus
IL-6 inhibitors
title Influence of anti-Spike protein antibody levels on tocilizumab efficacy in hospitalized patients with severe COVID-19 pneumonia: a post-hoc analysis of the COVACTA trial
title_full Influence of anti-Spike protein antibody levels on tocilizumab efficacy in hospitalized patients with severe COVID-19 pneumonia: a post-hoc analysis of the COVACTA trial
title_fullStr Influence of anti-Spike protein antibody levels on tocilizumab efficacy in hospitalized patients with severe COVID-19 pneumonia: a post-hoc analysis of the COVACTA trial
title_full_unstemmed Influence of anti-Spike protein antibody levels on tocilizumab efficacy in hospitalized patients with severe COVID-19 pneumonia: a post-hoc analysis of the COVACTA trial
title_short Influence of anti-Spike protein antibody levels on tocilizumab efficacy in hospitalized patients with severe COVID-19 pneumonia: a post-hoc analysis of the COVACTA trial
title_sort influence of anti spike protein antibody levels on tocilizumab efficacy in hospitalized patients with severe covid 19 pneumonia a post hoc analysis of the covacta trial
topic Tocilizumab
SARS-CoV-2
COVID-19
Antibodies
Serostatus
IL-6 inhibitors
url https://doi.org/10.1186/s12879-025-11001-6
work_keys_str_mv AT joseaguareles influenceofantispikeproteinantibodylevelsontocilizumabefficacyinhospitalizedpatientswithseverecovid19pneumoniaaposthocanalysisofthecovactatrial
AT carlesforne influenceofantispikeproteinantibodylevelsontocilizumabefficacyinhospitalizedpatientswithseverecovid19pneumoniaaposthocanalysisofthecovactatrial
AT anagarciacasas influenceofantispikeproteinantibodylevelsontocilizumabefficacyinhospitalizedpatientswithseverecovid19pneumoniaaposthocanalysisofthecovactatrial
AT guillermosantamariacorral influenceofantispikeproteinantibodylevelsontocilizumabefficacyinhospitalizedpatientswithseverecovid19pneumoniaaposthocanalysisofthecovactatrial
AT danielcarnevaliruiz influenceofantispikeproteinantibodylevelsontocilizumabefficacyinhospitalizedpatientswithseverecovid19pneumoniaaposthocanalysisofthecovactatrial
AT gabrielsotresfernandez influenceofantispikeproteinantibodylevelsontocilizumabefficacyinhospitalizedpatientswithseverecovid19pneumoniaaposthocanalysisofthecovactatrial
AT javiertsolera influenceofantispikeproteinantibodylevelsontocilizumabefficacyinhospitalizedpatientswithseverecovid19pneumoniaaposthocanalysisofthecovactatrial
AT pabloguisadovasco influenceofantispikeproteinantibodylevelsontocilizumabefficacyinhospitalizedpatientswithseverecovid19pneumoniaaposthocanalysisofthecovactatrial