ABSTRACT
Waning antibody responses after COVID-19 vaccination combined with the emergence of the SARS-CoV-2 Omicron lineage led to reduced vaccine effectiveness. As a countermeasure, bivalent mRNA-based booster vaccines encoding the ancestral spike protein in combination with that of Omicron BA.1 or BA.5 were introduced. Since then, BA.2-descendent lineages have become dominant, such as XBB.1.5 or BA.2.86. Here, we assessed how different COVID-19 priming regimens affect the immunogenicity of the recently used bivalent booster vaccinations and breakthrough infections. BA.1 and BA.5 bivalent vaccines boosted neutralizing antibodies and T-cells up to 3 months after boost; however, cross-neutralization of XBB.1.5 was poor. Interestingly, different combinations of prime-boost regimens induced divergent responses: participants primed with Ad26.COV2.S developed lower binding antibody levels after bivalent boost while neutralization and T-cell responses were similar to mRNA-based primed participants. In contrast, the breadth of neutralization was higher in mRNA-primed and bivalent BA.5 boosted participants. Combined, we highlight important "lessons learned" from the employed COVID-19 vaccination strategies. Our data further support the use of monovalent vaccines based on circulating strains when vaccinating risk groups, as recently recommended by the WHO. We emphasize the importance of the continuous assessment of immune responses targeting circulating variants to guide future COVID-19 vaccination policies.
Subject(s)
Protein S Deficiency , Breakthrough Pain , COVID-19ABSTRACT
Background Bivalent mRNA-based COVID-19 vaccines encoding the ancestral and Omicron spike protein were developed as a countermeasure against antigenically distinct SARS-CoV-2 variants. We compared the (variant-specific) immunogenicity and reactogenicity of mRNA-based bivalent Omicron BA.1 vaccines in individuals who were primed with adenovirus- or mRNA-based vaccines. Methods In this open-label, multicenter, randomized, controlled trial, healthcare workers primed with Ad26.COV2.S or mRNA-based vaccines were boosted with mRNA-1273.214 or BNT162b2 OMI BA.1. The primary endpoint was the fold change in S1-specific IgG antibodies pre- and 28 days after booster vaccination. Secondary outcomes were fast response, (antibody levels on day 7), reactogenicity, neutralization of circulating variants and (cross-reactive) SARS-CoV-2-specific T-cell responses. Findings No effect of different priming regimens was observed on bivalent vaccination boosted S1-specific IgG antibodies. The largest increase in S1-specific IgG antibodies occurred between day 0 and 7 after bivalent booster. Neutralizing antibodies targeting the variants in the bivalent vaccine (ancestral SARS-CoV-2 and Omicron BA.1) were boosted. In addition, neutralizing antibodies against the circulating Omicron BA.5 variant increased after BA.1 bivalent booster. T-cell responses were boosted and retained reactivity with variants from the Omicron sub-lineage. Interpretation Bivalent booster vaccination with mRNA-1273.214 or BNT162b2 OMI BA.1 resulted in a rapid recall of humoral and cellular immune responses independent of the initial priming regimen. Although no preferential boosting of variant-specific responses was observed, the induced antibodies and T-cells cross-reacted with Omicron BA.1 and BA.5. It remains crucial to monitor immunity at the population level, and simultaneously antigenic drift at the virus level, to determine the necessity (and timing) of COVID-19 booster vaccinations.
Subject(s)
COVID-19ABSTRACT
A large proportion of the global population received a single dose of the Ad26.COV2.S coronavirus disease-2019 (COVID-19) vaccine as priming vaccination, which was shown to provide protection against moderate to severe COVID-19. However, the emergence of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) variants that harbor immune-evasive mutations in the spike protein led to the recommendation of booster vaccinations after Ad26.COV2.S priming. Recent studies showed that heterologous booster vaccination with an mRNA-based vaccine following Ad26.COV2.S priming leads to high antibody levels. However, how heterologous booster vaccination affects other functional aspects of the immune response remains unknown. Here, we performed immunological profiling on samples obtained from Ad26.COV2.S-vaccinated individuals before and after a homologous (Ad26.COV2.S) or heterologous (mRNA-1273 or BNT162b2) booster vaccination. Both homologous and heterologous booster vaccination increased antibodies with multiple functionalities towards ancestral SARS-CoV-2, the Delta and Omicron BA.1 variants. Especially, mRNA-based booster vaccination induced high levels of neutralizing antibodies and antibodies with various Fc-mediated effector functions such as antibody-dependent cellular cytotoxicity and phagocytosis. In contrast, T cell responses were similar in magnitude following homologous or heterologous booster vaccination, and retained functionality towards Delta and Omicron BA.1. However, only heterologous booster vaccination with an mRNA-based vaccine led to the expansion of SARS-CoV-2-specific T cell clones, without an increase in the breadth of the T cell repertoire as assessed by T cell receptor sequencing. In conclusion, we show that Ad26.COV2.S priming vaccination provides a solid immunological base for heterologous boosting with an mRNA-based COVID-19 vaccine, increasing humoral and cellular responses targeting newly emerging variants of concern.
Subject(s)
Coronavirus Infections , Drug-Related Side Effects and Adverse Reactions , COVID-19ABSTRACT
Summary Background In the general population, illness after infection with the SARS-CoV-2 Omicron variant is less severe compared with previous variants. Data on the disease burden of Omicron in immunocompromised patients are lacking. We investigated the clinical characteristics and outcome of a cohort of immunocompromised patients with COVID-19 caused by Omicron. Methods Solid organ transplant recipients, patients on anti-CD20 therapy, and allogenic hematopoietic stem cell transplantation recipients on immunosuppressive therapy infected with the Omicron variant, were included. Patients were contacted regularly until symptom resolution. Clinical characteristics of consenting patients were collected through their electronic patient files. To identify possible risk factors for hospitalization, a univariate logistic analysis was performed. Findings A total of 114 consecutive immunocompromised patients(88% after a solid organ transplant) were enrolled. Eighty-nine percent had previously received three mRNA vaccinations. While only one patient died, 23(20%) required hospital admission for a median of 11 days. A low SARS-CoV-2 IgG antibody response(<300 BAU/mL) at diagnosis, higher age, being a lung transplant recipient, more comorbidities and a higher frailty were associated with hospital admission(all p<0.01). At the end of follow-up, 25% had still not fully recovered. Of the 23 hospitalized patients, 70% had a negative and 92% a low IgG (<300 BAU/mL) antibody response at admission. Sotrovimab was administered to 17 of them, of which one died. Interpretation While the mortality in immunocompromised patients infected with Omicron was low, hospital admission was frequent and the duration of symptoms often prolonged. Besides vaccination, other interventions are needed to limit the morbidity from COVID-19 in immunocompromised patients. Funding None.
Subject(s)
COVID-19ABSTRACT
BackgroundVaccines can be less immunogenic in people living with HIV (PLWH), but for SARS-CoV-2 vaccinations this is unknown. Methods and FindingsA prospective cohort study to examine the immunogenicity of BNT162b2, mRNA-1273, ChAdOx1-S and Ad26.COV2.S vaccines in adult PLWH, without prior COVID-19, compared to HIV-negative controls. The primary endpoint was the anti-spike SARS-CoV-2 IgG response after mRNA vaccination. Secondary endpoints included the serological response after vector vaccination, anti-SARS-CoV-2 T-cell response and reactogenicity. Between February-September 2021, 1154 PLWH (median age 53 [IQR 44-60], 86% male) and 440 controls (median age 43 [IQR 33-53], 29% male) were included. 884 PLWH received BNT162b2, 100 mRNA-1273, 150 ChAdOx1-S, and 20 Ad26.COV2.S. 99% were on antiretroviral therapy, 98% virally suppressed, and the median CD4+T-cell count was 710 cells/{micro}L [IQR 520-913]. 247 controls received mRNA-1273, 94 BNT162b2, 26 ChAdOx1-S and 73 Ad26.COV2.S. After mRNA vaccination, geometric mean concentration was 1418 BAU/mL in PLWH (95%CI 1322-1523), and after adjustment for age, sex, and vaccine type, HIV-status remained associated with a decreased response (0.607, 95%CI 0.508-0.725). In PLWH vaccinated with mRNA-based vaccines, higher antibody responses were predicted by CD4+T-cell counts 250-500 cells/{micro}L (2.845, 95%CI 1.876-4.314) or >500 cells/{micro}L (2.936, 95%CI 1.961-4.394), whilst a viral load >50 copies/mL was associated with a reduced response (0.454, 95%CI 0.286-0.720). Increased IFN-{gamma}, CD4+, and CD8+T-cell responses were observed after stimulation with SARS-CoV-2 spike peptides in ELISpot and activation induced marker assays, comparable to controls. Reactogenicity was generally mild without vaccine-related SAE. ConclusionAfter vaccination with BNT162b2 or mRNA-1273, anti-spike SARS-CoV-2 antibody levels were reduced in PLWH. To reach and maintain the same serological responses and vaccine efficacy as HIV-negative controls, additional vaccinations are probably required.
Subject(s)
COVID-19 , HIV InfectionsABSTRACT
Introduction: Only 60% of atrial fibrillation (AF) patients with elevated stroke risk receive anticoagulation (AC). Closing this gap in AC use is particularly challenging in the face of the COVID19 pandemic. Electronic health record (EHR) alerts integrated into in-person and telehealth visits have the potential to close the gap. Hypothesis: A triad approach consisting of interventions at the practice provider at patient level could improve anticoagulation rates in patients with atrial fibrillation. Methods: In collaboration with the Heart Rhythm Society Quality Improvement Committee and UMass, University of Florida (UFL) Jacksonville launched a 2020 quality improvement (QI) intervention, including several Plan-Do-Study-Act (PDSA) cycles, centered around an outpatient, electronic health record (EHR) alert linked to an order set for AC meds, labs, and specialty referrals. The alert fired when cardiologists or primary care physicians saw AF patients in clinic with a CHA2DS2-VASc score of ≥2 who were not on AC. Due to COVID-19, several of the PDSA interventions required adjustments due to redeployment of information technology staff mobilized to generate COVID-19 reports, a pivot for clinicians and patients to telehealth visits, and a change in clinician and patient priorities from routine cardiovascular/preventive care to COVID-19 diagnosis and prevention. To assess intervention effectiveness, the change in AC use as a function of time was measured using a weighted least squares linear regression. Results: At time of launch, 2357 of 3555 eligible patients (56.3%) were on AC. At study end, six months later, the percentage of patients on AC increased by 1.5% to 57.8 %. Based on the population of untreated patients at UFL and the stroke rate for untreated patients (available from large registry data), and assuming absence of any competing/secular trend to explain the growth in AC use, we calculated that a 1.5% increase in the AC treatment percentage could result in the prevention of 1.5 strokes over one year. Conclusion: We demonstrated that an EHR alert can raise the rate of AC use in patients with AF after several rounds of PDSAs. In future efforts, we plan to reassess the AC percentage in our population and confirm the sustainability of our QI efforts as attention focuses back from the pandemic to routine cardiovascular/ preventive care.