Short-term effectiveness of COVID-19 vaccines in immunocompromised patients: A systematic literature review and meta-analysis

Effectiveness of heterologous and homologous COVID-19 vaccination among immunocompromised individuals: a systematic literature review and meta-analysis

Objectives

We assessed the effectiveness of heterologous vaccination strategy in immunocompromised individuals regarding COVID-19 outcomes, comparing it to homologous approaches.

Design

Systematic literature review/meta-analysis.

Methods

We searched PubMed, CINAHL, EMBASE, Cochrane Central Register of Controlled Trials, Scopus, and Web of Science from January 1, 2020 to September 29, 2023. We included studies that evaluated the heterologous vaccination strategy on immunocompromised individuals through outcomes related to COVID-19 (levels of anti-SARS-CoV-2 spike protein IgG, neutralizing antibodies, symptomatic COVID-19 infection, hospitalization, and death) in comparison to homologous schemes. We also used random-effect models to produce pooled odds ratio estimates. Heterogeneity was investigated with I2 estimation.

Results

Eighteen studies met the inclusion criteria for this systematic review. Fourteen of them provided quantitative data for inclusion in the meta-analysis on vaccine response, being four of them also included in the vaccine effectiveness meta-analysis. The vaccination strategies (heterologous vs homologous) showed no difference in the odds of developing anti-SARS-CoV-2 spike protein IgG (odds ratio 1.12 [95% Cl: 0.73-1.72]). Heterologous schemes also showed no difference in the production of neutralizing antibodies (odds ratio 1.48 [95% Cl: 0.72-3.05]) nor vaccine effectiveness in comparison to homologous schemes (odds ratio 1.52 [95% CI: 0.66-3.53]).

Conclusions

Alternative heterologous COVID-19 vaccinations have shown equivalent antibody response rates and vaccine effectiveness to homologous schemes, potentially aiding global disparity of vaccine distribution.

Comparison Study of the Bio-Plex and Meso Scale Multiplexed SARS-CoV-2 Serology Assays Reveals Evidence of Diminished Host Antibody Responses to SARS-CoV-2 after Monoclonal Antibody Treatment

Background

Assessing the breadth and duration of antigen-specific binding antibodies provides valuable information for evaluating interventions to treat or prevent SARS-CoV-2 infection. Multiplex immunoassays are a convenient method for rapid measurement of antibody responses but can sometimes provide discordant results, and antibody positive percent agreement for COVID-19 diagnosis can vary depending on assay type, disease severity, and population sampled. Therefore, we compared two assays marked for research applications, MSD and Bio-Plex Pro, to evaluate qualitative interpretation of serostatus and quantitative detection of antibodies of varying isotypes (IgG, IgM, and IgA) against receptor binding domain (RBD) and nucleocapsid (N) antigens.

Methods

Specimens from ACTIV-2/A5401, a placebo-controlled clinical trial of the SARSCoV-2 monoclonal antibody (mAb) bamlanivimab to prevent COVID-19 disease progression, were used to evaluate the concordance of the Bio-Rad Bio-Plex Pro Human SARS-CoV-2 Serology Assay and the Meso Scale Discovery (MSD) V-PLEX COVID-19 Panel 1 serology assay in detecting and quantifying IgG, IgA, and IgM binding anti-SARS-CoV-2 antibody responses against the RBD and N antigens. Data were disaggregated by study arm, bamlanivimab dose, days post-enrollment, and presence of emerging resistance.

Results

We observed 90.5% (412 of 455 tests) concordance for anti-RBD IgG and 87% (396 of 455) concordance for anti-N IgG in classifying samples as negative or positive based on assay-defined cutoffs. Antibody levels converted to the WHO standard BAU/mL were significantly correlated for all isotypes (IgG, IgM, and IgA) and SARS-CoV-2 antigen targets (RBD and N) tested that were common between the two assays (Spearman r 0.65 to 0.92, P < 0.0001). Both assays uncovered evidence of diminished host-derived IgG immune responses in participants treated with bamlanivimab compared to placebo. Assessment of immune responses in the four individuals treated with the 700 mg of bamlanivimab with emerging mAb resistance demonstrated a stronger anti-N IgG response (MSD) at day 28 (median 2.18 log BAU/mL) compared to participants treated with bamlanivimab who did not develop resistance (median 1.55 log BAU/mL).

Conclusions

These data demonstrate the utility in using multiplex immunoassays for characterizing the immune responses with and without treatment in a study population and provide evidence that monoclonal antibody treatment in acute COVID-19 may have a modest negative impact on development of host IgG responses.

Using virtual patient cohorts to uncover immune response differences in cancer and immunosuppressed COVID-19 patients

The COVID-19 pandemic caused by the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) resulted in millions of deaths globally. Adults with immunosuppression (e.g., solid organ transplant recipients) and those undergoing active cancer treatments experience worse infections and more severe COVID-19. It is difficult to conduct clinical studies in these populations, resulting in a restricted amount of data that can be used to relate mechanisms of immune dysfunction to COVID-19 outcomes in these vulnerable groups. To study immune dynamics after infection with SARS-CoV-2 and to investigate drivers of COVID-19 severity in individuals with cancer and immunosuppression, we adapted our mathematical model of the immune response during COVID-19 and generated virtual patient cohorts of cancer and immunosuppressed patients. The cohorts of plausible patients recapitulated available longitudinal clinical data collected from patients in Montréal, Canada area hospitals. Our model predicted that both cancer and immunosuppressed virtual patients with severe COVID-19 had decreased CD8+ T cells, elevated interleukin-6 concentrations, and delayed type I interferon peaks compared to those with mild COVID-19 outcomes. Additionally, our results suggest that cancer patients experience higher viral loads (however, with no direct relation with severity), likely because of decreased initial neutrophil counts (i.e., neutropenia), a frequent toxic side effect of anti-cancer therapy. Furthermore, severe cancer and immunosuppressed virtual patients suffered a high degree of tissue damage associated with elevated neutrophils. Lastly, parameter values associated with monocyte recruitment by infected cells were found to be elevated in severe cancer and immunosuppressed patients with respect to the COVID-19 reference group. Together, our study highlights that dysfunction in type I interferon and CD8+ T cells are key drivers of immune dysregulation in COVID-19, particularly in cancer patients and immunosuppressed individuals.

Risk of breakthrough infection and hospitalisation after COVID-19 primary vaccination by HIV status in four Italian regions during 2021

BACKGROUND

As of 2024, vaccination remains the main mitigation measure against COVID-19, but there are contradictory results on whether people living with HIV (PLWH) are less protected by vaccines than people living without HIV (PLWoH). In this study we compared the risk of SARS-CoV-2 infection and COVID-19 hospitalisation following full vaccination in PLWH and PLWoH.

METHODS

We linked data from the vaccination registry, the COVID-19 surveillance system and from healthcare/pharmacological registries in four Italian regions. We identified PLWH fully vaccinated (14 days post completion of the primary cycle) and matched them at a ratio of 1:4 with PLWoH by week of vaccine administration, age, sex, region of residence and comorbidities. Follow-up started on January 24, 2021, and lasted for a maximum of 234 days. We used the Kaplan-Meier estimator to calculate the cumulative incidence of infection and COVID-19 hospitalisation in both groups, and we compared risks using risk differences and ratios taking PLWoH as the reference group.

RESULTS

We matched 42,771 PLWH with 171,084 PLWoH. The overall risk of breakthrough infection was similar in both groups with a rate ratio (RR) of 1.10 (95% confidence interval (CI):0.80-1.53). The absolute difference between groups at the end of the study period was 8.28 events per 10,000 person-days in the PLWH group (95%CI:-18.43-40.29). There was a non-significant increase the risk of COVID-19 hospitalisation among PLWH (RR:1.90; 95%CI:0.93-3.32) which corresponds to 6.73 hospitalisations per 10,000 individuals (95%CI: -0.57 to 14.87 per 10,000).

CONCLUSIONS

Our findings suggest PLWH were not at increased risk of breakthrough SARS-CoV-2 infection or COVID-19 hospitalisation following a primary cycle of mRNA vaccination.

Vaccination of Adults With Cancer: ASCO Guideline

PURPOSE

To guide the vaccination of adults with solid tumors or hematologic malignancies.

METHODS

A systematic literature review identified systematic reviews, randomized controlled trials (RCTs), and nonrandomized studies on the efficacy and safety of vaccines used by adults with cancer or their household contacts. This review builds on a 2013 guideline by the Infectious Disease Society of America. PubMed and the Cochrane Library were searched from January 1, 2013, to February 16, 2023. ASCO convened an Expert Panel to review the evidence and formulate recommendations.

RESULTS

A total of 102 publications were included in the systematic review: 24 systematic reviews, 14 RCTs, and 64 nonrandomized studies. The largest body of evidence addressed COVID-19 vaccines.

RECOMMENDATIONS

The goal of vaccination is to limit the severity of infection and prevent infection where feasible. Optimizing vaccination status should be considered a key element in the care of patients with cancer. This approach includes the documentation of vaccination status at the time of the first patient visit; timely provision of recommended vaccines; and appropriate revaccination after hematopoietic stem-cell transplantation, chimeric antigen receptor T-cell therapy, or B-cell-depleting therapy. Active interaction and coordination among healthcare providers, including primary care practitioners, pharmacists, and nursing team members, are needed. Vaccination of household contacts will enhance protection for patients with cancer. Some vaccination and revaccination plans for patients with cancer may be affected by the underlying immune status and the anticancer therapy received. As a result, vaccine strategies may differ from the vaccine recommendations for the general healthy adult population vaccine.Additional information is available at www.asco.org/supportive-care-guidelines.

Immunogenicity and safety of a quadrivalent recombinant influenza vaccine manufactured in Iran (FluGuard) in volunteers aged 18-60 years: A double-blind, non-inferiority, randomized controlled trial

BACKGROUND

This study aimed to evaluate the non-inferiority of the FluGuard (a quadrivalent recombinant vaccine manufactured by Nivad Pharmed Salamat Company in Iran) by comparing its immunogenicity and safety with Vaxigrip Tetra (a quadrivalent inactivated vaccine manufactured by Sanofi Pasteur in France).

MATERIALS AND METHODS

In this double-blind, randomized controlled trial, eligible volunteers aged 18-60 were randomized to receive either FluGuard or Vaxigrip Tetra vaccines. Immunogenicity was evaluated using the Hemagglutination Inhibition (HAI) assay and reported with the geometric mean titer (GMT), seroprotection, and seroconversion. In addition, vaccine safety was assessed by interviewing participants through phone calls.

RESULTS

Out of 110 randomized volunteers, 51 and 53 were entered into the final analysis in the Vaxigrip and FluGuard groups, respectively. Vaxigrip had a higher seroprotection rate for the H1N1 strain compared with FluGuard (98 % vs. 91 %). Besides, FluGuard had higher seroprotection rates for H3N2 (74 % vs. 69 %), B-Yamagata (87 % vs. 84 %), and B-Victoria (66 % vs. 41 %) strains compared with Vaxigrip. In all four strains, FluGuard was non-inferior to Vaxigrip with the upper bounds of the 95 % CI on the ratio of the GMTs < 1.5: H1N1 (1.25), H3N2 (0.94), B-Yamagata (0.62), and B-Victoria (0.59). Furthermore, FluGuard was non-inferior to Vaxigrip with the upper bounds of the 95 % CI on the difference between the seroconversion rates < 10 %: H1N1 (2 %), H3N2 (10 %), B-Yamagata (-10 %), and B-Victoria (-29 %). The prevalence of solicited adverse drug reactions did not differ between groups. Furthermore, participants did not experience serious adverse events.

CONCLUSION

Our findings support the non-inferiority of the FluGuard vaccine to the Vaxigrip vaccine regarding immunogenicity and safety.

CLINICAL TRIAL REGISTRY

The study protocol was approved by the Iranian Registry of Clinical Trials (IRCT20210901052358N5).

Managing acute COVID-19 in immunocompromised pediatric patients

INTRODUCTION

SARS-CoV-2 infection is a potentially life-threatening infection in immunocompromised pediatric patients, and its management has rapidly evolved during the pandemic. To control SARS-CoV-2 infection over time, the scenario changed for the better with the introduction of specific treatments such as antiviral drugs, vaccines, and monoclonal antibodies, together with drugs blocking the inflammatory cytokine cascade and improvements in supportive care.

AREAS COVERED

This paper discusses the therapeutic strategies to apply for patients affected by COVID-19 in the pediatric population, with a focus on the immunocompromised patients.

EXPERT OPINION

Treatment in pediatric patients retraces the therapies investigated and approved in adults and must be calibrated on the basis of the severity of the infection (anti-spike monoclonal antibody, antivirals, anti-inflammatory drugs, and immunomodulators). Transmission prevention policies and vaccination reduce the risk of infection, while early intervention in the immunocompromised patients at high-risk of progression to severe-critical COVID-19 may reduce the period of viral shedding and the need for hospitalization, intensive care admission, and death. In hemato-oncological patients, the delayed treatment of SARS-CoV-2 infection or COVID-19 disease represents a frequent complication and its impact on the patient outcome remains a matter of research for the next few years.

AZD1222 effectiveness against severe COVID-19 in individuals with comorbidity or frailty: The RAVEN cohort study

OBJECTIVES

Despite being prioritized during initial COVID-19 vaccine rollout, vulnerable individuals at high risk of severe COVID-19 (hospitalization, intensive care unit admission, or death) remain underrepresented in vaccine effectiveness (VE) studies. The RAVEN cohort study (NCT05047822) assessed AZD1222 (ChAdOx1 nCov-19) two-dose primary series VE in vulnerable populations.

METHODS

Using the Oxford-Royal College of General Practitioners Clinical Informatics Digital Hub, linked to secondary care, death registration, and COVID-19 datasets in England, COVID-19 outcomes in 2021 were compared in vaccinated and unvaccinated individuals matched on age, sex, region, and multimorbidity.

RESULTS

Over 4.5 million AZD1222 recipients were matched (mean follow-up ∼5 months); 68% were ≥50 years, 57% had high multimorbidity. Overall, high VE against severe COVID-19 was demonstrated, with lower VE observed in vulnerable populations. VE against hospitalization was higher in the lowest multimorbidity quartile (91.1%; 95% CI: 90.1, 92.0) than the highest quartile (80.4%; 79.7, 81.1), and among individuals ≥65 years, higher in the 'fit' (86.2%; 84.5, 87.6) than the frailest (71.8%; 69.3, 74.2). VE against hospitalization was lowest in immunosuppressed individuals (64.6%; 60.7, 68.1).

CONCLUSIONS

Based on integrated and comprehensive UK health data, overall population-level VE with AZD1222 was high. VEs were notably lower in vulnerable groups, particularly the immunosuppressed.

Determinants of SARS-CoV-2 IgG response and decay in Canadian healthcare workers: A prospective cohort study

INTRODUCTION

Healthcare workers (HCWs) from an interprovincial Canadian cohort gave serial blood samples to identify factors associated with anti-receptor binding domain (anti-RBD) IgG response to the SARS-CoV-2 virus.

METHODS

Members of the HCW cohort donated blood samples four months after their first SARS-CoV-2 immunization and again at 7, 10 and 13 months. Date and type of immunizations and dates of SARS-CoV-2 infection were collected at each of four contacts, together with information on immunologically-compromising conditions and current therapies. Blood samples were analyzed centrally for anti-RBD IgG and anti-nucleocapsid IgG (Abbott Architect, Abbott Diagnostics). Records of immunization and SARS-CoV-2 testing from public health agencies were used to assess the impact of reporting errors on estimates from the random-effects multivariable model fitted to the data.

RESULTS

2752 of 4567 vaccinated cohort participants agreed to donate at least one blood sample. Modelling of anti-RBD IgG titer from 8903 samples showed an increase in IgG with each vaccine dose and with first infection. A decrease in IgG titer was found with the number of months since vaccination or infection, with the sharpest decline after the third dose. An immunization regime that included mRNA1273 (Moderna) resulted in higher anti-RBD IgG. Participants reporting multiple sclerosis, rheumatoid arthritis or taking selective immunosuppressants, tumor necrosis factor inhibitors, calcineurin inhibitors and antineoplastic agents had lower anti-RBD IgG. Supplementary analyses showed higher anti-RBD IgG in those reporting side-effects of vaccination, no relation of anti-RBD IgG to obesity and lower titers in women immunized in early or mid-pregnancy. Sensitivity analysis results suggested no important bias in the self-report data.

CONCLUSION

Creation of a prospective cohort was central to the credibility of results presented here. Serial serology assessments, with longitudinal analysis, provided effect estimates with enhanced accuracy and a clearer understanding of medical and other factors affecting response to vaccination.

A systematic review and meta-analysis of the global prevalence and determinants of COVID-19 vaccine acceptance and uptake in people living with HIV

People living with HIV (PLHIV) are at higher risk of poor outcomes of SARS-CoV-2 infection. Here we report the pooled prevalence of COVID-19 vaccine acceptance/uptake and determinants among this vulnerable population of PLHIV based on a systematic review and meta-analysis of studies published by 25 August 2023. Among the 54 included studies (N = 167,485 participants), 53 (N = 166,455) provided data on vaccine acceptance rate, while 27 (N = 150,926) provided uptake data. The global prevalences of COVID-19 vaccine acceptance and uptake were 67.0% and 56.6%, respectively. Acceptance and uptake rates were 86.6% and 90.1% for the European Region, 74.9% and 71.6% for the Region of the Americas, 62.3% and 78.9% for the South-East Asian Region, 64.6% and 19.3% for the Eastern Mediterranean Region, 58.0% and 35.5% for the African Region, and 57.4% and 44.0% for the Western Pacific Region. The acceptance rate increased from 65.9% in 2020 to 71.0% in 2022, and the uptake rate increased from 55.9% in 2021 to 58.1% in 2022. Men, PLHIV aged ≥40 years and those who had recently received the influenza vaccine were more likely to accept and receive the COVID-19 vaccine. Factors associated with lower uptake included Black race, other races (Latinx/Hispanic/mixed race), low education level and being unemployed. Vaccine-related factors associated with higher acceptance included belief in vaccine effectiveness, vaccine trust, perceived high susceptibility to SARS-CoV-2 infection and fear of potential COVID-19 effect in PLHIV. Sustained efforts and targeted interventions are needed to reduce regional disparities in COVID-19 vaccine uptake among PLHIV.

Humoral and cellular response to the COVID-19 vaccine in immunocompromised children

BACKGROUND

A suboptimal response to the 2-dose COVID-19 vaccine series in the immunocompromised population prompted recommendations for a 3rd primary dose. We aimed to determine the humoral and cellular immune response to the 3rd COVID-19 vaccine in immunocompromised children.

METHODS

Prospective cohort study of immunocompromised participants, 5-21 years old, who received 2 prior doses of an mRNA COVID-19 vaccine. Humoral and CD4/CD8 T-cell responses were measured to SARS-CoV-2 spike antigens prior to receiving the 3rd vaccine dose and 3-4 weeks after the 3rd dose was given.

RESULTS

Of the 37 participants, approximately half were solid organ transplant recipients. The majority (86.5%) had a detectable humoral response after the 2nd and 3rd vaccine doses, with a significant increase in antibody levels after the 3rd dose. Positive T-cell responses increased from being present in 86.5% to 100% of the cohort after the 3rd dose.

CONCLUSIONS

Most immunocompromised children mount a humoral and cellular immune response to the 2-dose COVID-19 vaccine series, which is significantly augmented after receiving the 3rd vaccine dose. This supports the utility of the 3rd vaccine dose and the rationale for ongoing emphasis for vaccination against COVID-19 in this population.

IMPACT

Most immunocompromised children mount a humoral and cellular immune response to the 2-dose COVID-19 vaccine series, which is significantly augmented after receiving the 3rd vaccine dose. This is the first prospective cohort study to analyze both the humoral and T-cell immune response to the 3rd COVID-19 primary vaccine dose in children who are immunocompromised. The results of this study support the utility of the 3rd vaccine dose and the rationale for ongoing emphasis for vaccination against COVID-19 in the immunosuppressed pediatric population.

Differential cellular and humoral immune responses in immunocompromised individuals following multiple SARS-CoV-2 vaccinations

Introduction

The heterogeneity of the immunocompromised population means some individuals may exhibit variable, weak or reduced vaccine-induced immune responses, leaving them poorly protected from COVID-19 disease despite receiving multiple SARS-CoV-2 vaccinations. There is conflicting data on the immunogenicity elicited by multiple vaccinations in immunocompromised groups. The aim of this study was to measure both humoral and cellular vaccine-induced immunity in several immunocompromised cohorts and to compare them to immunocompetent controls.

Methods

Cytokine release in peptide-stimulated whole blood, and neutralising antibody and baseline SARS-CoV-2 spike-specific IgG levels in plasma were measured in rheumatology patients (n=29), renal transplant recipients (n=46), people living with HIV (PLWH) (n=27) and immunocompetent participants (n=64) post third or fourth vaccination from just one blood sample. Cytokines were measured by ELISA and multiplex array. Neutralising antibody levels in plasma were determined by a 50% neutralising antibody titre assay and SARS-CoV-2 spike specific IgG levels were quantified by ELISA.

Results

In infection negative donors, IFN-γ, IL-2 and neutralising antibody levels were significantly reduced in rheumatology patients (p=0.0014, p=0.0415, p=0.0319, respectively) and renal transplant recipients (p<0.0001, p=0.0005, p<0.0001, respectively) compared to immunocompetent controls, with IgG antibody responses similarly affected. Conversely, cellular and humoral immune responses were not impaired in PLWH, or between individuals from all groups with previous SARS-CoV-2 infections.

Discussion

These results suggest that specific subgroups within immunocompromised cohorts could benefit from distinct, personalised immunisation or treatment strategies. Identification of vaccine non-responders could be critical to protect those most at risk.

Real-World Safety of COVID-19 mRNA Vaccines: A Systematic Review and Meta-Analysis

With the mass vaccination program for COVID-19 mRNA vaccines, there has been sufficient real-world study (RWS) on the topic to summarize their safety in the total population and in immunocompromised (IC) patients who were excluded from phase 3 clinical trials. We conducted a systematic review and meta-analysis to evaluate the safety of COVID-19 mRNA vaccines, with a total of 5,132,799 subjects from 122 articles. In the case of the total population vaccinated with first, second, and third doses, the pooled incidence of any adverse events (AEs) was 62.20%, 70.39%, and 58.60%; that of any local AEs was 52.03%, 47.99%, and 65.00%; that of any systemic AEs was 29.07%, 47.86%, and 32.71%. Among the immunocompromised patients, the pooled odds ratio of any AEs, any local AEs, and systemic AEs were slightly lower than or similar to those of the healthy controls at 0.60 (95% CI: 0.33-1.11), 0.19 (95% CI: 0.10-0.37), and 0.36 (95% CI: 0.25-0.54), with pooled incidences of 51.95%, 38.82%, and 31.00%, respectively. The spectrum of AEs associated with the vaccines was broad, but most AEs were transient, self-limiting, and mild to moderate. Moreover, younger adults, women, and people with prior SARS-CoV-2 infection were more likely to experience AEs.

Effectiveness of vaccination against SARS-CoV-2 and the need for alternative preventative approaches in immunocompromised individuals: a narrative review of systematic reviews

INTRODUCTION

Vaccination against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), including administration of booster doses, continues to be the most effective method for controlling COVID-19-related complications including progression to severe illness and death.However, there is mounting evidence that more needs to be done to protect individuals with compromised immune function.

AREAS COVERED

Here, we review the effectiveness of COVID-19 vaccination in immunocompromised patients, including those with primary immunodeficiencies, HIV, cancer (including hematological malignancies), solid organ transplant recipients and chronic kidney disease, as reported in systematic reviews/meta-analyses published over a 12-month period in PubMed. Given the varied responses to vaccination patients with compromised immune function, a major goal of this analysis was to try to identify specific risk-factors related to vaccine failure.

EXPERT OPINION

COVID-19 remains a global problem, with new variants of concern emerging at regular intervals. There is an ongoing need for optimal vaccine strategies to combat the pandemic. In addition, alternative treatment approaches are needed for immunocompromised patients who may not mount an adequate immune response to current COVID-19 vaccines. Identification of high-risk patients, and the introduction of newer antiviral approaches such as monoclonal antibodies, will offer physicians therapeutic options for such vulnerable individuals.

Importance, Applications and Features of Assays Measuring SARS-CoV-2 Neutralizing Antibodies

More than three years ago, the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) caused the unforeseen COVID-19 pandemic with millions of deaths. In the meantime, SARS-CoV-2 has become endemic and is now part of the repertoire of viruses causing seasonal severe respiratory infections. Due to several factors, among them the development of SARS-CoV-2 immunity through natural infection, vaccination and the current dominance of seemingly less pathogenic strains belonging to the omicron lineage, the COVID-19 situation has stabilized. However, several challenges remain and the possible new occurrence of highly pathogenic variants remains a threat. Here we review the development, features and importance of assays measuring SARS-CoV-2 neutralizing antibodies (NAbs). In particular we focus on in vitro infection assays and molecular interaction assays studying the binding of the receptor binding domain (RBD) with its cognate cellular receptor ACE2. These assays, but not the measurement of SARS-CoV-2-specific antibodies per se, can inform us of whether antibodies produced by convalescent or vaccinated subjects may protect against the infection and thus have the potential to predict the risk of becoming newly infected. This information is extremely important given the fact that a considerable number of subjects, in particular vulnerable persons, respond poorly to the vaccination with the production of neutralizing antibodies. Furthermore, these assays allow to determine and evaluate the virus-neutralizing capacity of antibodies induced by vaccines and administration of plasma-, immunoglobulin preparations, monoclonal antibodies, ACE2 variants or synthetic compounds to be used for therapy of COVID-19 and assist in the preclinical evaluation of vaccines. Both types of assays can be relatively quickly adapted to newly emerging virus variants to inform us about the magnitude of cross-neutralization, which may even allow us to estimate the risk of becoming infected by newly appearing virus variants. Given the paramount importance of the infection and interaction assays we discuss their specific features, possible advantages and disadvantages, technical aspects and not yet fully resolved issues, such as cut-off levels predicting the degree of in vivo protection.

Effectiveness of COVID-19 vaccines in people living with HIV in British Columbia and comparisons with a matched HIV-negative cohort: a test-negative design

OBJECTIVES

We estimated the effectiveness of COVID-19 vaccines against laboratory-confirmed SARS-CoV-2 infection among people living with HIV (PLWH) and compared the estimates with a matched HIV-negative cohort.

METHODS

We used the British Columbia COVID-19 Cohort, a population-based data platform, which integrates COVID-19 data on SARS-CoV-2 tests, laboratory-confirmed cases, and immunizations with provincial health services data. The vaccine effectiveness (VE) was estimated with a test-negative design using the multivariable logistic regression.

RESULTS

The adjusted VE against SARS-CoV-2 infection was 71.1% (39.7, 86.1%) 7-59 days after two doses, rising to 89.3% (72.2, 95.9%) between 60 and 89 days. VE was preserved 4-6 months after the receipt of two doses, after which noticeable waning was observed (51.3% [4.8, 75.0%]). In the matched HIV-negative cohort (n = 375,043), VE peaked at 91.4% (90.9, 91.8%) 7-59 days after two doses and was sustained for up to 4 months, after which evidence of waning was observed, dropping to 84.2% (83.4, 85.0%) between 4 and 6 months.

CONCLUSION

The receipt of two COVID-19 vaccine doses was effective against SARS-CoV-2 infection among PLWH pre-Omicron. VE estimates appeared to peak later in PLWH than in the matched HIV-negative cohort and the degree of waning was relatively quicker in PLWH; however, peak estimates were comparable in both populations.

A simple point-of-care assay accurately detects anti-spike antibodies after SARS-CoV-2 vaccination

Objective

Lateral flow assays (LFA) are sensitive for detecting antibodies to SARS-CoV-2 proteins within weeks after infection. This study tested samples from immunocompetent adults, and those receiving treatments for chronic inflammatory diseases (CID), before and after mRNA SARS-CoV-2 vaccination.

Methods

We compared results obtained with the COVIBLOCK Covid-19 LFA to those obtained by anti-spike (S) ELISA.

Results

The LFA detected anti-S antibodies in 29 of 29 (100%) of the immunocompetent and 110 of 126 (87.3%) of the CID participants after vaccination. Semiquantitative LFA scores were statistically significantly lower in samples from immunosuppressed participants, and were significantly correlated with anti-S antibody levels measured by ELISA.

Conclusions

This simple LFA test is a practical alternative to laboratory-based assays for detecting anti-S antibodies after infection or vaccination. This type of test may be most useful for testing people in outpatient or resource-limited settings.

Pediatric Systemic Lupus Erythematous in COVID-19 Era

Pediatric systemic lupus erythematosus is a chronic autoimmune disorder with a highly variable course and prognosis. It results in functional abnormalities in the immune system due to intrinsic factors and the use of immunosuppressive therapies associated with underlying comorbidities seem to increase the risk of severe COVID-19 and poor outcomes of the disease in pediatric systemic lupus erythematosus (SLE) patients. The aim of this review is to obtain a better understanding of the existing link between this new viral infection and pediatric lupus. We have analyzed the characteristics of newly diagnosed cases of pediatric SLE following COVID-19 which have been reported in the literature and which describe the impact that COVID-19 has on patients already suffering with pediatric SLE.

Therapeutic potential of compounds targeting SARS-CoV-2 helicase

The economical and societal impact of COVID-19 has made the development of vaccines and drugs to combat SARS-CoV-2 infection a priority. While the SARS-CoV-2 spike protein has been widely explored as a drug target, the SARS-CoV-2 helicase (nsp13) does not have any approved medication. The helicase shares 99.8% similarity with its SARS-CoV-1 homolog and was shown to be essential for viral replication. This review summarizes and builds on existing research on inhibitors of SARS-CoV-1 and SARS-CoV-2 helicases. Our analysis on the toxicity and specificity of these compounds, set the road going forward for the repurposing of existing drugs and the development of new SARS-CoV-2 helicase inhibitors.

Immunogenicity and safety of COVID-19 vaccine in lung cancer patients receiving anticancer treatment: A prospective multicenter cohort study

This study assessed the immunogenicity and safety of the BNT162b2 mRNA vaccine in lung cancer patients receiving anticancer treatment. We enrolled lung cancer patients receiving anticancer treatment and non-cancer patients; all participants were fully vaccinated with the BNT162b2 vaccine. Blood samples were collected before the first and second vaccinations and 4 ± 1 weeks after the second vaccination. Anti-severe respiratory syndrome coronavirus-2 (SARS-CoV-2) spike protein S1 subunit receptor-binding domain antibody titers were measured using the Architect SARS-CoV-2 IgG II Quant and Elecsys Anti-SARS-CoV-2 S assays. Fifty-five lung cancer patients and 38 non-cancer patients were included in the immunogenicity analysis. Lung cancer patients showed significant increase in the geometric mean antibody concentration, which was significantly lower than that in the non-cancer patients after the first (30 vs. 121 AU/mL, p < .001 on Architect; 4.0 vs 1.2 U/mL, p < .001 on Elecsys) and second vaccinations (1632 vs. 3472 AU/mL, p = .005 on Architect; 213 vs 573 A/mL, p = .002 on Elecsys). The adjusted odds ratio (aOR) for seroprotection was significantly lower (p < .05) in lung cancer patients than that in non-cancer patients. Analysis of the anticancer treatment types showed that the aOR for seroprotection was significantly lower (p < .05) in lung cancer patients receiving cytotoxic agents. They showed no increase in adverse reactions. BNT162b2 vaccination in lung cancer patients undergoing anticancer treatment significantly increased (p < .05) antibody titers and showed acceptable safety. Immunogenicity in these patients could be inadequate compared with that in non-cancer patients.

COVID-19 vaccine response and safety in patients with cancer: An overview of systematic reviews

Background

To date, the COVID-19 pandemic does not appear to be overcome with new variants continuously emerging. The vaccination against COVID-19 has been the trend, but there are multiple systematic reviews on COVID-19 vaccines in patients with cancer, resulting in redundant and sub-optimal systematic reviews. There are still some doubts about efficacy and safety of the COVID-19 vaccine in cancer patients.

Purpose

To identify, summarize and synthesize the available evidence of systematic reviews on response and COVID-19 vaccine safety in patients with cancer.

Methods

Multiple databases were searched from their inception to May 1, 2022 to fetch the relevant articles. Study quality was assessed by AMSTAR2. The protocol of this study was registered on PROSPERO (CRD42022327931).

Results

A total of 18 articles were finally included. The seroconversion rates after first dose were ranged from 37.30-54.20% in all cancers, 49.60-62.00% in solid cancers and 33.30-56.00% in hematological malignancies. The seroconversion rates after second dose were ranged from 65.30-87.70% in all cancers, 91.60-96.00% in solid cancers and 58.00-72.60% in hematological malignancies. Cancer types and types of therapy could influence vaccine response. COVID-19 vaccines were safe and well-tolerated.

Conclusions

This study suggests COVID-19 vaccine response is significantly lower in cancer patients. Number of received doses, cancer types and treatment strategies could influence response of COVID-19 vaccine in cancer patients. COVID-19 vaccines are safe and well-tolerated. Considering the emergence of several new variants of SARS-CoV-2 with potential influence on ongoing vaccination programs, there is a need for booster doses to increase the effectiveness of COVID-19 vaccines.

Systematic review registration

https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022327931, identifier CRD42022327931.

A multinational Delphi consensus to end the COVID-19 public health threat

Despite notable scientific and medical advances, broader political, socioeconomic and behavioural factors continue to undercut the response to the COVID-19 pandemic1,2. Here we convened, as part of this Delphi study, a diverse, multidisciplinary panel of 386 academic, health, non-governmental organization, government and other experts in COVID-19 response from 112 countries and territories to recommend specific actions to end this persistent global threat to public health. The panel developed a set of 41 consensus statements and 57 recommendations to governments, health systems, industry and other key stakeholders across six domains: communication; health systems; vaccination; prevention; treatment and care; and inequities. In the wake of nearly three years of fragmented global and national responses, it is instructive to note that three of the highest-ranked recommendations call for the adoption of whole-of-society and whole-of-government approaches1, while maintaining proven prevention measures using a vaccines-plus approach2 that employs a range of public health and financial support measures to complement vaccination. Other recommendations with at least 99% combined agreement advise governments and other stakeholders to improve communication, rebuild public trust and engage communities3 in the management of pandemic responses. The findings of the study, which have been further endorsed by 184 organizations globally, include points of unanimous agreement, as well as six recommendations with >5% disagreement, that provide health and social policy actions to address inadequacies in the pandemic response and help to bring this public health threat to an end.

Factors Associated With COVID-19 Vaccine Response in Transplant Recipients: A Systematic Review and Meta-analysis

BACKGROUND

The rapid development and universal access to vaccines represent a milestone in combating the coronavirus disease 2019 (COVID-19) pandemic. However, there are major concerns about vaccine response in immunocompromised populations in particular transplant recipients. In the present study, we aim to comprehensively assess the humoral response to COVID-19 vaccination in both orthotopic organ transplant and allogeneic hematopoietic stem cell transplant recipients.

METHODS

We performed a systematic review and meta-analysis of 96 studies that met inclusion criteria.

RESULTS

The pooled rates of seroconversion were 49% (95% confidence interval [CI], 43%-55%) in transplant recipients and 99% (95% CI, 99%-99%) in healthy controls after the second dose of vaccine. The pooled rate was 56% (95% CI, 49%-63%) in transplant recipients after the third dose. Immunosuppressive medication is the most prominent risk factor associated with seroconversion failure, but different immunosuppressive regimens are associated with differential outcomes in this respect. Calcineurin inhibitors, steroids, or mycophenolate mofetil/mycophenolic acid are associated with an increased risk of seroconversion failure, whereas azathioprine or mammalian target of rapamycin inhibitors do not. Advanced age, short interval from receiving the vaccine to the time of transplantation, or comorbidities confers a higher risk for seroconversion failure.

CONCLUSIONS

Transplant recipients compared with the general population have much lower rates of seroconversion upon receiving COVID-19 vaccines. Immunosuppressants are the most prominent factors associated with seroconversion, although different types may have differential effects.

A Systematic Review and Meta-Analysis of Serologic Response following Coronavirus Disease 2019 (COVID-19) Vaccination in Solid Organ Transplant Recipients

Solid organ transplant (SOT) recipients are at greater risk of coronavirus disease 2019 (COVID-19) and have attenuated response to vaccinations. In the present meta-analysis, we aimed to evaluate the serologic response to the COVID-19 vaccine in SOT recipients. A search of electronic databases was conducted to identify SOT studies that reported the serologic response to COVID-19 vaccination. We analyzed 44 observational studies including 6158 SOT recipients. Most studies were on mRNA vaccination (mRNA-1273 or BNT162b2). After a single and two doses of vaccine, serologic response rates were 8.6% (95% CI 6.8-11.0) and 34.2% (95% CI 30.1-38.7), respectively. Compared to controls, response rates were lower after a single and two doses of vaccine (OR 0.0049 [95% CI 0.0021-0.012] and 0.0057 [95% CI 0.0030-0.011], respectively). A third dose improved the rate to 65.6% (95% CI 60.4-70.2), but in a subset of patients who had not achieved a response after two doses, it remained low at 35.7% (95% CI 21.2-53.3). In summary, only a small proportion of SOT recipients achieved serologic response to the COVID-19 mRNA vaccine, and that even the third dose had an insufficient response. Alternative strategies for prophylaxis in SOT patients need to be developed. Key Contribution: In this meta-analysis that included 6158 solid organ transplant recipients, the serologic response to the COVID-19 vaccine was extremely low after one (8.6%) and two doses (34.2%). The third dose of the vaccine improved the rate only to 66%, and in the subset of patients who had not achieved a response after two doses, it remained low at 36%. The results of our study suggest that a significant proportion of solid organ transplant recipients are unable to achieve a sufficient serologic response after completing not only the two series of vaccination but also the third booster dose. There is an urgent need to develop strategies for prophylaxis including modified vaccine schedules or the use of monoclonal antibodies in this vulnerable patient population.

Publication trends of research on COVID-19 and host immune response: A bibliometric analysis

Introduction

As the first bibliometric analysis of COVID-19 and immune responses, this study will provide a comprehensive overview of the latest research advances. We attempt to summarize the scientific productivity and cooperation across countries and institutions using the bibliometric methodology. Meanwhile, using clustering analysis of keywords, we revealed the evolution of research hotspots and predicted future research focuses, thereby providing valuable information for the follow-up studies.

Methods

We selected publications on COVID-19 and immune response using our pre-designed search strategy. Web of Science was applied to screen the eligible publications for subsequent bibliometric analyses. GraphPad Prism 8.0, VOSviewer, and CiteSpace were applied to analyze the research trends and compared the contributions of countries, authors, institutions, and journals to the global publications in this field.

Results

We identified 2,200 publications on COVID-19 and immune response published between December 1, 2019, and April 25, 2022, with a total of 3,154 citations. The United States (611), China (353), and Germany (209) ranked the top three in terms of the number of publications, accounting for 53.3% of the total articles. Among the top 15 institutions publishing articles in this area, four were from France, four were from the United States, and three were from China. The journal Frontiers in Immunology published the most articles (178) related to COVID-19 and immune response. Alessandro Sette (31 publications) from the United States were the most productive and influential scholar in this field, whose publications with the most citation frequency (3,633). Furthermore, the development and evaluation of vaccines might become a hotspot in relevant scope.

Conclusions

The United States makes the most indispensable contribution in this field in terms of publication numbers, total citations, and H-index. Although publications from China also take the lead regarding quality and quantity, their international cooperation and preclinical research need to be further strengthened. Regarding the citation frequency and the total number of published articles, the latest research progress might be tracked in the top-ranking journals in this field. By analyzing the chronological order of the appearance of retrieved keywords, we speculated that vaccine-related research might be the novel focus in this field.

Impact of vaccination on the symptoms of hospitalised patients with SARS-CoV-2 delta variant (B.1.617.1) infection

OBJECTIVES

The diffusion of the SARS-CoV-2 delta (B.1.617.2) variant and the waning of immune response after primary Covid-19 vaccination favoured the breakthrough SARS-CoV-2 infections in vaccinated subjects. To assess the impact of vaccination, we determined the severity of infection in hospitalised patients according to vaccine status.

METHODS

We performed a retrospectiveobservational study on patients hospitalised in 10 centres with a SARS-CoV-2 infection (delta variant) from July to November 2021 by including all patients who had completed their primary vaccination at least 14 days before hospital admission and the same number of completely unvaccinated patients. We assessed the impact of vaccination and other risk factors through logistic regression.

RESULTS

We included 955 patients (474 vaccinated and 481 unvaccinated). Vaccinated patients were significantly older (75.0 [63.25-84.0] vs. 55.0 [38.0-73.0]; p<0.001), more frequently males (55.1% (261/474) vs. 46.4% (223/481); p=0.009), and had more comorbidities (2.0 [1.0-3.0] vs. 1.0 [0.0-2.0]; p<0.001). Vaccinated patients were less often admitted for Covid-19 (59.3% (281/474) vs. 75.1% (361/481); p<0.001), had less extended lung lesions (≤25%: 64.3% (117/182) vs. 38.4% (88/229); p<0.001), required oxygen less frequently (57.5% (229/398) vs. 73.0% (270/370); p<0.001), at a lower flow (3.0 [0.0-8.7] vs. 6.0 [2.0-50.0] L/min, p<0.001), and for a shorter duration (3 [0.0-8.0] vs. 6 [2.0-12.0] days, p<0.001)., and required less frequently intensive care unit admission (16.2% (60/370) vs. 36.0% (133/369); p<0.001) but had comparable mortality in bivariate analysis (16.7% (74/443) vs. 12.2% (53/433); p=0.075). Multivariate logistic regression showed that vaccination significantly decreased the risk of death (0.38 [0.20-0.70](p=0.002), ICU admission (0.31 [0.21-0.47](p<0.001) and oxygen requirement (0.16 [0.10-0.26](p<0.001), even among older patients or with comorbidities.

CONCLUSIONS

Among patients hospitalised with a delta variant SARS-CoV-2 infection, vaccination was associated with less severe forms, even in the presence of comorbidities.

A Systematic Review of Coronavirus Disease 2019 Vaccine Efficacy and Effectiveness Against Severe Acute Respiratory Syndrome Coronavirus 2 Infection and Disease

Billions of doses of coronavirus disease 2019 (COVID-19) vaccines have been administered globally, dramatically reducing severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) incidence and severity in some settings. Many studies suggest vaccines provide a high degree of protection against infection and disease, but precise estimates vary and studies differ in design, outcomes measured, dosing regime, location, and circulating virus strains. In this study, we conduct a systematic review of COVID-19 vaccines through February 2022. We included efficacy data from Phase 3 clinical trials for 15 vaccines undergoing World Health Organization Emergency Use Listing evaluation and real-world effectiveness for 8 vaccines with observational studies meeting inclusion criteria. Vaccine metrics collected include protection against asymptomatic infection, any infection, symptomatic COVID-19, and severe outcomes including hospitalization and death, for partial or complete vaccination, and against variants of concern Alpha, Beta, Gamma, Delta, and Omicron. We additionally review the epidemiological principles behind the design and interpretation of vaccine efficacy and effectiveness studies, including important sources of heterogeneity.

Vaccination for the Prevention of Infection among Immunocompromised Patients: A Concise Review of Recent Systematic Reviews

Vaccination is crucial for avoiding infection-associated morbidity and mortality among immunocompromised patients. However, immunocompromised patients respond less well to vaccinations compared to healthy people, and little is known about the relative efficacy of various vaccines among different immunocompromised states. A total of 54 systematic reviews (22 COVID-19; 32 non-COVID-19) published within the last 5 years in Pubmed® were reviewed. They demonstrated similar patterns within three seroconversion response categories: good (about >60% when compared to healthy controls), intermediate (~40−60%), and poor (about <40%). Good vaccine responses would be expected for patients with chronic kidney disease, human immunodeficiency virus infection (normal CD4 counts), immune-mediated inflammatory diseases, post-splenectomy states, and solid tumors. Intermediate vaccine responses would be expected for patients with anti-cytotoxic T-lymphocyte antigen-4 therapy, hematologic cancer, and human immunodeficiency virus infection (low CD4 counts). Poor vaccine responses would be expected for patients with B-cell-depleting agents (e.g., anti-CD20 therapy), hematopoietic stem-cell transplant, solid organ transplant, and liver cirrhosis. For all vaccine response categories, vaccination should be timed when patients are least immunosuppressed. For the intermediate and poor vaccine response categories, high-dose vaccine, revaccination when patients are less immunosuppressed, checking for seroconversion, additional booster doses, and long-acting monoclonal antibodies may be considered, supplemented by shielding measures.

Autoimmune post-COVID vaccine syndromes: does the spectrum of autoimmune/inflammatory syndrome expand?

To date, around 60% of the world population has been protected by vaccines against SARS-CoV-2, significantly reducing the devastating effect of the pandemic and restoring social economic activity through mass vaccination. Multiple studies have demonstrated the effectiveness and safety of vaccines against COVID-19 in healthy populations, in people with risk factors, in people with or without SARS-CoV-2 infection, and in immunocompromised people. According to the criteria for post-vaccine adverse events established by the World Health Organization, a minority of individuals may develop adverse events, including autoimmune syndromes. The exact mechanisms for the development of these autoimmune syndromes are under study, and to date, a cause-effect relationship has not been established. Many of these autoimmune syndromes meet sufficient criteria for the diagnosis of Adjuvant-Induced Autoimmune Syndrome (ASIA syndrome). The descriptions of these autoimmune syndromes open new perspectives to the knowledge of the complex relationship between the host, its immune system, with the new vaccines and the development of new-onset autoimmune syndromes. Fortunately, most of these autoimmune syndromes are easily controlled with steroids and other immunomodulatory medications and are short-lived. Rheumatologists must be alert to the development of these autoimmune syndromes, and investigate the relationship between autoimmune/inflammatory symptoms and vaccination time, and assess their therapeutic response.

Prevalence of Anti-SARS-CoV-2 Antibodies and Potential Determinants among the Belgian Adult Population: Baseline Results of a Prospective Cohort Study

The prevalence of anti-SARS-CoV-2 antibodies and potential determinants were assessed in a random sample representative of the Belgian adult population. In total, 14,201 individuals (≥18 years) were invited by mail to provide saliva via an Oracol^® swab. Survey weights were applied, and potential determinants were estimated using multivariable logistic regressions. Between March and August 2021, 2767 individuals participated in the first data collection. During this period, which coincided with the onset of the vaccination campaign, the seroprevalence in the population increased from 25.2% in March/April to 78.1% in July. Among the vaccinated there was an increase from 74,2% to 98.8%; among the unvaccinated, the seroprevalence remained stable (around 17%). Among the vaccinated, factors significantly associated with the presence of antibodies were: having at least one chronic disease (OR_a 0.22 (95% CI 0.08–0.62)), having received an mRNA-type vaccine (OR_a 5.38 (95% CI 1.72–16.80)), and having received an influenza vaccine in 2020–2021 (OR_a 3.79 (95% CI 1.30–11.07)). Among the unvaccinated, having a non-O blood type (OR_a 2.00 (95% CI 1.09–3.67)) and having one or more positive COVID-19 tests (OR_a 11.04 (95% CI 4.69–26.02)) were significantly associated. This study provides a better understanding of vaccine- and/or natural-induced presence of anti-SARS-CoV-2 antibodies and factors that are associated with this presence.

Autoimmune post-COVID vaccine syndromes: does the spectrum of autoimmune/inflammatory syndrome expand?

To date, around 60% of the world population has been protected by vaccines against SARS-CoV-2, significantly reducing the devastating effect of the pandemic and restoring social economic activity through mass vaccination. Multiple studies have demonstrated the effectiveness and safety of vaccines against COVID-19 in healthy populations, in people with risk factors, in people with or without SARS-CoV-2 infection, and in immunocompromised people. According to the criteria for post-vaccine adverse events established by the World Health Organization, a minority of individuals may develop adverse events, including autoimmune syndromes. The exact mechanisms for the development of these autoimmune syndromes are under study, and to date, a cause-effect relationship has not been established. Many of these autoimmune syndromes meet sufficient criteria for the diagnosis of Adjuvant-Induced Autoimmune Syndrome (ASIA syndrome). The descriptions of these autoimmune syndromes open new perspectives to the knowledge of the complex relationship between the host, its immune system, with the new vaccines and the development of new-onset autoimmune syndromes. Fortunately, most of these autoimmune syndromes are easily controlled with steroids and other immunomodulatory medications and are short-lived. Rheumatologists must be alert to the development of these autoimmune syndromes, and investigate the relationship between autoimmune/inflammatory symptoms and vaccination time, and assess their therapeutic response.

Lack of Induction of RBD-Specific Neutralizing Antibodies despite Repeated Heterologous SARS-CoV-2 Vaccination Leading to Seroconversion and Establishment of T Cell-Specific Memory in a Patient in Remission of Multiple Myeloma

Background: Prophylactic vaccination against infectious diseases may induce a state of long-term protection in the otherwise healthy host. However, the situation is less predictable in immunocompromised patients and may require adjustment of vaccination schedules and/or basic therapy. Methods: A patient in full remission of multiple myeloma since the last three years and on long-term maintenance therapy with pomalidomide, a drug inhibiting angiogenesis and myeloma cell growth, was vaccinated twice with Comirnaty followed by two vaccinations with Vaxzevria. Seroconversion and SARS-CoV-2-specific cellular responses were monitored. Results: No signs of seroconversion or T cellular memory were observed after the first “full immunization” with Comirnaty. Consequently, long-term-maintenance therapy with Pomalidomide was stopped and two additional shots of Vaxzevria were administered after which the patient seroconverted with Spike(S)-protein specific antibody levels reaching 49 BAU/mL, mild S-peptide pool-specific T cell proliferation, effector cytokine production (IL-2, IL-13), and T cellular activation with increased numbers of CD3⁺CD4⁺CD25⁺ T cells as compared to vaccinated and non-vaccinated control subjects. However, despite suspension of immunosuppression and administration of in total four consecutive heterologous SARS-CoV-2 vaccine shots, the patient did not develop neutralizing RBD-specific antibodies. Conclusions: Despite immunomonitoring-based adjustment of vaccination and/or therapy schedules vaccination success, with clear correlates of protection, the development of RBD-specific antibodies could not be achieved in the immunocompromised patient with current SARS-CoV-2 vaccines. Thus, our report emphasizes the need for improved active and passive immunization strategies for SARS-CoV-2 infections.

Multiple Sclerosis Patients and Disease Modifying Therapies: Impact on Immune Responses against COVID-19 and SARS-CoV-2 Vaccination

This article reviews the literature on SARS-CoV-2 pandemic and multiple sclerosis (MS). The first part of the paper focuses on the current data on immunopathology of SARS-CoV-2 and leading vaccines produced against COVID-19 infection. In the second part of the article, we discuss the effect of Disease Modifying Therapies (DMTs) on COVID-19 infection severity or SARS-CoV-2 vaccination in MS patients plus safety profile of different vaccine platforms in MS patients.