Predictors of poor seroconversion and adverse events to SARS-CoV-2 mRNA BNT162b2 vaccine in cancer patients on active treatment

Time-Dependent Effects of Clinical Interventions on SARS-CoV-2 Immunity in Patients with Lung Cancer

In patients with lung cancer (LC), understanding factors that impact the dynamics of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) anti-spike antibody (SAb) titers over time is critical, but challenging, due to evolving treatments, infections, vaccinations, and health status. The objective was to develop a time-dependent regression model elucidating individual contributions of factors influencing SAb levels in LC patients using a prospective, longitudinal, multi-institutional cohort study initiated in January 2021. The study evaluated 296 LC patients-median age 69; 55% female; 50% stage IV. Blood samples were collected every three months to measure SAb levels using FDA-approved ELISA. Asymptomatic and unreported infections were documented through measurement of anti-nucleocapsid Ab levels (Meso Scale Discovery). Associations between clinical characteristics and titers were evaluated using a time-dependent linear regression model with a generalized estimating equation (GEE), considering time-independent variables (age, sex, ethnicity, smoking history, histology, and stage) and time-dependent variables (booster vaccinations, SARS-CoV-2 infections, cancer treatment, steroid use, and influenza vaccination). Significant time-dependent effects increasing titer levels were observed for prior SARS-CoV-2 infection (p < 0.001) and vaccination/boosters (p < 0.001). Steroid use (p = 0.043) and chemotherapy (p = 0.033) reduced titer levels. Influenza vaccination was associated with increased SAb levels (p < 0.001), independent of SARS-CoV-2 vaccine boosters. Prior smoking significantly decreased titers in females (p = 0.001). Age showed no association with titers. This GEE-based linear regression model unveiled the nuanced impact of multiple variables on patient anti-spike Ab levels over time. After controlling for the major influences of vaccine and SARS-CoV-2 infections, chemotherapy and steroid use were found to have negatively affected titers. Smoking in females significantly decreased titers. Surprisingly, influenza vaccinations were also significantly associated, likely indirectly, with improved SARS-CoV-2 titers.

Immunogenicity after vaccination of COVID-19 vaccines in patients with cancer: a prospective, single center, observational study

BACKGROUND

Patients with cancer, particularly those undergoing chemotherapy, are at risk from the low immunogenicity of Coronavirus Disease 19 (COVID-19) vaccines.

METHODS

This prospective study assessed the seroconversion rate of COVID-19 vaccines among patients with cancer and hospital staff. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein-specific IgG (S-IgG) concentrations were evaluated before the first vaccination, and 1-3 and 4-6 months after the second vaccination. The primary endpoint was the seroconversion rate measured 1-3 months after the second vaccine.

RESULTS

In total, 590 patients and 183 healthy hospital staff were analyzed. At 1-3 months after the second vaccination, the S-IgG antibody concentration exceeded the cut-off value (20 BAU/mL) in 96.1% (567/590) of the patients with cancer and 100% (183/183) of the healthy controls (p = 0.0024). At 4-6 months after the second vaccination, the S-IgG antibody concentration exceeded the cut-off value (20 BAU/ml for S-IgG) in 93.1% (461/495) of the patients with cancer and 100% (170/170) of the healthy controls (p < 0.0001). Old age, being male, and low lymphocyte count were related to low SARS-CoV-2 S-IgG levels 1-3 months after the second vaccination among patients, while body mass index, smoking history, and serum albumin level were not. Patients undergoing platinum combination therapy and alkylating agent among cytotoxic drugs, and PARP inhibitor, mTOR inhibitor, and BCR-ABL inhibitor exhibited a low S-IgG antibody concentration compared to the no treatment group.

CONCLUSIONS

COVID-19 vaccine immunogenicity was reduced among patients with cancer, especially under several treatment regimens.

SARS-CoV-2 vaccination willingness and humoral vaccination response in radiation oncology patients

BACKGROUND

SARS-CoV-2 infection has been and, in some parts, still is a threat to oncologic patients, making it crucial to understand perception of vaccination and immunologic responses in this vulnerable patient segment. SARS-CoV-2 vaccines in relation to malignant disease characteristics and therapies have so far not been studied consecutively in larger oncologic patient populations. This study captures SARS-CoV-2 vaccination willingness and humoral immune response in a large consecutive oncologic patient collective at the beginning of 2021.

METHODS

1142 patients were consecutively recruited over 5.5 months at a tertiary department for radiation oncology and were assessed for vaccination willingness via a standardized interview. In already vaccinated patients total SARS-CoV-2 S antibody titres against the spike protein (Anti-SARS-CoV-2 S) and were evaluated 35 days or later after the first dose of SARS-CoV-2 vaccine.

RESULTS

Vaccination willingness was high with a rate of 90 %. The most frequent reasons for rejection were: undecided/potential vaccination after therapy, distrust in the vaccine and fear of interaction with comorbidities. Factors associated with lower vaccination willingness were: worse general condition, lower age and female sex. 80 % of the participants had been previously vaccinated, 8 % reported previous infection and 16 % received vaccination during antineoplastic therapy. In 97.5 % of the vaccinated patients Anti-SARS-CoV-2 S was detected. In a univariable analysis parameters associated with non-conversion were: lower performance status, spread to the local lymphatics (N + ), hematologic disease and diffuse metastases. All patients with oligometastatic disease achieved positive Anti-SARS-CoV-2 S titres. For patients with two vaccinations several risk factors were identified, that were associated with low antibody concentrations.

CONCLUSIONS

SARS-CoV-2 vaccination willingness among oncologic patients was high in the first months after its availability, and most patients had already received one or two doses. Over 97 % of vaccinated patients had measurable anti-SARS-CoV-2 S titres. Our data supports early identification of low humoral responders after vaccination and could facilitate the design of future oncologic vaccine trials (clinicaltrials.gov Identifier: NCT04918888).

Serological response and immune-related adverse events following COVID-19 vaccination in cancer patients treated with immune checkpoint inhibitors: A systematic review and meta-analysis

With the popularity of Coronavirus disease 2019 (COVID-19) vaccine and the development of vaccination strategies, the impact of COVID-19 vaccine on cancer patients receiving immune checkpoint inhibitors (ICIs) is still unclear. In the systematic review and meta-analysis of patients with ICIs, we assessed the serological response of cancer patients receiving COVID-19 vaccine, and explored the risk of immune related adverse events (irAEs). We searched PubMed, EMBASE and Cochrane Library as of 10 June 2023, and included cancer patients who received ICIs and COVID-19 vaccine. The systematic review and meta-analysis include cohort study, cross-sectional study and case report. The outcome included the serological response, Spike-specific T-cell response, irAEs and rare adverse events. When possible, the data were analysed by random effect analysis, and the statistical heterogeneity was assessed by Q-test and I2 statistics. We explored the sources of heterogeneity through L'Abbe plots, Galbraith radial plots, and sensitivity analysis. The publication bias was evaluated by Egger's, Begg's linear regression test and funnel plot, and the impact of publication bias was further analysed by trim and fill method. 27 studies were eligible (19 cohort studies, 1 cross-sectional study and 7 case reports), involving 8331 patients (with 4724 receiving ICIs). Most studies used mRNA vaccine (BNT162b2 or mRNA-1273). Compared with cancer patients receiving chemotherapy, cancer patients receiving ICIs were significantly more likely to have seroconversion (RR = 1.05, 95%CI 1.01-1.10, P = 0.02). There were no statistically significant differences in seroconversion rates when comparing cancer patients receiving ICIs with controls without cancer (RR = 0.95, 95% CI 0.89-1.01, P = 0.09) or with cancer patients receiving targeted therapy (RR = 1.05, 95% CI 0.79-1.39, P = 0.75). The incidence of irAEs in patients receiving ICIs before and after COVID-19 vaccination was (21.96%, 95%CI 16.66%-28.94%) and (14.88%, 95%CI 8.65%-25.57%), respectively. The most common irAEs were endocrine abnormalities, skin disorders, etc. The certainty of evidence was low in cancer patients with ICIs, compared with those receiving chemotherapy, and very low versus controls without cancer. Cancer patients treated with ICIs seem to be able to receive COVID-19 vaccine safely without increasing the incidence of irAEs.

Immunologic Signatures of Peripheral Blood T Cells Reveal the Outcome of p53MVA Vaccine and Pembrolizumab Treatment in Patients with Advanced Ovarian Cancer

PURPOSE

Our previous studies indicated that p53-reactive T cells were associated with clinical benefit in patients with advanced ovarian cancer who were treated with p53-expressing modified vaccinia Ankara (p53MVA) vaccine and gemcitabine chemotherapy. To replace chemotherapy with an approach that will enhance vaccine efficacy and antitumor immunity, we treated patients with p53MVA in combination with PD-1 checkpoint blocker, pembrolizumab. We also attempted to further characterize the activation status of T cells prior to vaccination and during treatment.

EXPERIMENTAL DESIGN

Patients received up to three triweekly vaccinations concurrent with pembrolizumab, followed by pembrolizumab monotherapy at 3-week intervals. Correlative studies analyzed peripheral blood T-cell phenotypes and profiles of immune function gene expression.

RESULTS

We observed 6/28 (21%) patients with a clinical benefit to therapy, including 3 partial responses (PR) and 3 patients with stable disease (SD) for 6+ months. The median progression-free survival was 1.8 months (95% confidence interval: 1.7-3.8) and median overall survival was 15.1 months (9.4-30.4). Two patients remain progression-free at 28 and 33 months. Of the 18 patients evaluable in correlative studies, 6 were immunologic responders of whom 5 had clinical benefit (3 PR, 2 SD). Immunologic non-responders expressed in pretreatment peripheral blood mononuclear cell samples high levels of mRNA for multiple molecules associated with terminally differentiated T cells.

CONCLUSIONS

p53MVA/pembrolizumab immunotherapy showed promising antitumor activity in patients who demonstrated functionally competent peripheral blood T cells. Detection of markers of terminally differentiated T cells before treatment may identify patients unlikely to respond to p53MVA/pembrolizumab.

SIGNIFICANCE

The activity of a combination immunotherapy of p53 vaccine and PD-1 checkpoint blockade in patients with platinum-resistant ovarian cancer was evaluated in a phase II trial. Clinical benefit was correlated with the responsive immune status of patients before and during the treatment, defining potential predictive markers for immune therapy.

COVID-19 Infection despite Previous Vaccination in Cancer Patients and Healthcare Workers: Results from a French Prospective Multicenter Cohort (PAPESCO-19)

In a multicenter prospective cohort of cancer patients (CP; n = 840) and healthcare workers (HCWs; n = 935) vaccinated against COVID-19, we noticed the following: i/after vaccination, 4.4% of HCWs and 5.8% of CP were infected; ii/no characteristic was associated with post-vaccine COVID-19 infections among HCWs; iii/CP who developed infections were younger, more frequently women (NS), more frequently had gastrointestinal, gynecological, or breast cancer and a localized cancer stage; iv/CP vaccinated while receiving chemotherapy or targeted therapy had (NS) more breakthrough infections after vaccination than those vaccinated after these treatments; the opposite was noted with radiotherapy, immunotherapy, or hormonotherapy; v/most COVID-19 infections occurred either during the Alpha wave (11/41 HCW, 20/49 CP), early after the first vaccination campaign started, or during the Omicron wave (21/41 HCW, 20/49 CP), more than 3 months after the second dose; vi/risk of infection was not associated with values of antibody titers; vii/the outcome of these COVID-19 infections after vaccination was not severe in all cases. To conclude, around 5% of our CPs or HCWs developed a COVID-19 infection despite previous vaccination. The outcome of these infections was not severe.

COVID-19 Vaccination Safety Profiles in Patients With Solid Tumour Cancers: A Systematic Review

Vaccination has become an essential means of protection for solid tumour patients against coronavirus disease 2019 (COVID-19). In this systematic review, we sought to identify common safety profiles of the COVID-19 vaccine in patients with solid tumours. A search of Web of Science, PubMed, EMBASE and Cochrane was conducted for studies in English full-text that reported side-effect data experienced by patients with cancer who were at least 12 years old with solid tumours or a recent history of solid tumours after receiving either one or multiple doses of the COVID-19 vaccination. Study quality was assessed with the Newcastle Ottawa Scale criteria. Acceptable study types were retrospective and prospective cohorts, retrospective and prospective observational studies, observational analyses and case series; systematic reviews, meta-analyses and case reports were excluded. Among local/injection site symptoms, the most commonly reported were injection site pain and ipsilateral axillary/clavicular lymphadenopathy, whereas the most commonly reported systemic effects were fatigue/malaise, musculoskeletal symptoms and headache. Most side-effects reported were characterised as mild to moderate. A thorough evaluation of the randomised controlled trials for each featured vaccine led to the conclusion that in the USA and abroad, the safety profile seen in patients with solid tumours is comparable with that seen in the general public.

Serological Response to SARS-CoV-2 after COVID-19 Vaccination in Lung Cancer Patients: Short Review

In comparison to the general population, lung cancer patients are more likely to suffer from severe Coronavirus disease (COVID-19) and associated mortality. Considering this increased risk, and in order to prevent symptoms and severe disease, patients with lung cancer have been prioritized for COVID-19 vaccination primary and booster doses. Despite this, the pivotal clinical trials did not include these patients, which leaves open questions regarding vaccine efficacy and humoral immune response. This review outlines the findings of recent investigations into the humoral responses of lung cancer patients to COVID-19 vaccination, particularly the primary doses and first boost.

Effectiveness and Safety of COVID-19 Vaccination in Patients with Malignant Disease

A novel virus named SARS-CoV-2 has caused a worldwide pandemic, resulting in a disastrous impact to the public health since 2019. The disease is much more lethal among patients with malignant disease. Vaccination plays an important role in the prevention of infection and subsequent severe COVID-19. However, the efficacy and safety of vaccines for cancer patients needs further investigation. Encouragingly, there have been important findings deduced from research so far. In this review, an overview of the immunogenicity, effectiveness, and safeness of COVID-19 vaccines in patients with cancer to date is to be shown. We also highlight important questions to consider and directions that could be followed in future research.

COVID-19 vaccination in patients with cancer receiving immune checkpoint inhibitors: a systematic review and meta-analysis

BACKGROUND

Immune checkpoint inhibitors (ICI) can cause off-target inflammatory and immune-related adverse events (irAE). Conceivably, COVID-19 vaccination could trigger an inflammatory and immune response that could induce or aggravate irAE.

METHODS

The objective of this systematic review is to appraise the efficacy and safety of COVID-19 vaccination in patients with cancer treated with ICI. The literature search was performed in PubMed and Embase in English from December 2019 to February 2022. The review included clinical trials, observational cohort studies, case series, and case reports reporting on the clinical efficacy and safety of COVID-19 vaccines on patients with cancer treated with ICI. Outcomes of interest included seroconversion, SARS-CoV-2 infection rate, severe COVID-19, COVID-19 mortality rate. Incidence of ICI irAEs was also ascertained as well as vaccine adverse events. A meta-analysis was conducted to estimate the pooled effect sizes of the outcomes when possible, using random effects models.

RESULTS

Overall, 19 studies were included for the analysis (n=10 865 with 2477 receiving ICI). We analyzed 15 cohort studies, 1 cross-sectional study, and 3 case reports. There were no statistically significant differences in seroconversion rates after the second dose of the vaccine when comparing patients with cancer receiving ICI with patients without cancer (risk ratio, RR 0.97, 95% CI 0.92 to 1.03) or with patients with cancer without active treatment (RR 1.00, 95% CI 0.96 to 1.04). There was a higher probability of seroconversion in patients with cancer treated with ICI compared with patients with cancer treated with chemotherapy (RR 1.09, 95% CI 1.00 to 1.18). In a single study in patients receiving ICI, no differences were observed in risk of irAE between those receiving inactivated vaccine and those unvaccinated (pneumonitis RR 0.88, 95% CI 0.33 to 2.3; rash RR 1.03, 95% CI 0.66 to 1.62; arthralgia RR 0.94, 95% CI 0.51 to 1.75). There were no studies for other types of vaccines comparing vaccinated vs not vaccinated in patients treated with ICI. The most common vaccine-related adverse events were local pain or fatigue. Overall, the quality of evidence was rated as very low.

CONCLUSION

COVID-19 vaccination appears to be effective and safe in patients with cancer receiving ICI.

Longitudinal efficacy and toxicity of SARS-CoV-2 vaccination in cancer patients treated with immunotherapy

Despite more than 2 years having elapsed since the onset of SARS-CoV-2 pandemic, a level of hesitation around increased SARS-CoV-2 vaccine toxicity in cancer patients receiving immunotherapy (IO) remains. This hesitation stems from the idea that IO agents could elicit an overwhelming immune stimulation post vaccination and therefore increase the risk of vaccine-related toxicity. The aim of our study was to explore serological responses to SARS-CoV-2 vaccination in patients treated with IO and describe the level of immune stimulation using parameters such as blood cytokines, autoantibody levels and immune related adverse events (irAEs) post vaccination. Fifty-one evaluable patients were enrolled in this longitudinal study. Absolute levels and neutralization potential of anti-SARS-CoV-2 antibodies were not significantly different in the IO group compared to non-IO. Chemotherapy adversely affected seroconversion when compared to IO and/or targeted treatment. Following vaccination, the prevalence of grade ≥2 irAEs in patients treated with IO was not higher than the usual reported IO toxicity. We report, for the first time, that anti-SARS-CoV-2 vaccination, elicited the generation of five autoantibodies. The significantly increased autoantibodies were IgM autoantibodies against beta-2 glycoprotein (p = 0.02), myeloperoxidase (p = 0.03), nucleosome (p = 0.041), SPLUNC2 (p < 0.001) and IgG autoantibody against Myosin Heavy Chain 6 (MYH6) (p < 0.001). Overall, comprehensive analysis of a small cohort showed that co-administration of SARS-CoV-2 vaccine and IO is not associated with increased irAEs. Nevertheless, the detection of autoantibodies post anti-SARS-CoV-2 vaccination warrants further investigation (NCT03702309).

Immunogenicity assessment of elder hepatocellular carcinoma patients after inactivated whole-virion SARS-CoV-2 vaccination

BACKGROUND

Research on immunogenicity after 3rd SARS-CoV-2 vaccine in elder hepatocellular carcinoma (HCC) was limited. This study aimed to investigate the efficacy and influencing factors of inactivated SARS-CoV-2 vaccine in elder HCC.

RESEARCH DESIGN AND METHODS

We assessed total antibodies, anti-RBD IgG, and neutralizing antibodies (NAb) toward SARS-CoV-2 wild type (WT) as well as BA.4/5 in 304 uninfected HCC, 147 matched healthy control (HC), and 53 SARS-CoV-2 infected HCC, all aged over 60 years. The levels of antibodies were compared in the period 7-90, 91-180, and >180 days after 2nd or 3rd vaccination, respectively.

RESULTS

HCC had lower seropositivity than HC after 2nd dose (total antibodies, 64% vs. 92%, P < 0.0001; anti-RBD IgG, 50% vs. 77%, P < 0.0001). But 3rd dose can efficaciously close the gap (total antibodies, 96% vs. 100%, P = 0.1212; anti-RBD IgG: 87% vs. 87%, P > 0.9999). Booster effect of 3rd dose can persist >180 days in HCC (2nd vs. 3rd: total antibodies, 0.60 vs. 3.20, P < 0.0001; anti-RBD IgG, 13.86 vs. 68.85, P < 0.0001; WT NAb, 11.70 vs. 22.47, P < 0.0001). Vaccinated HCC had more evident humoral responses than unvaccinated ones after infection (total antibodies: 3.85 vs. 3.20, P < 0.0001; anti-RBD IgG: 910.92 vs. 68.85, P < 0.0001; WT NAb: 96.09 vs. 22.47, P < 0.0001; BA.4/5 NAb: 86.53 vs. 5.59, P < 0.0001).

CONCLUSIONS

Our findings highlight the booster effect and protective role of 3rd dose. Our results could provide a theoretical foundation for informing decisions regarding SARS-CoV-2 vaccination in elder HCC.

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.

Influence of the COVID-19 pandemic in the gastrointestinal oncology setting: An overview

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has been impacting healthcare in various ways worldwide and cancer patients are greatly affected by the coronavirus disease 2019 (COVID-19) pandemic. The reorganization of the health facilities in order to supply the high demand resulting from the aforementioned infection as well as the social isolation measures led to impairments for the diagnosis and follow-up of patients with gastrointestinal cancers, which has had an impact on the prognosis of the oncologic patients. In that context, health authorities and organizations have elaborated new guidelines with specific recommendations for the management of individuals with gastrointestinal neoplasms during the pandemic. Of note, oncologic populations seem to be more susceptible to unfavorable outcomes when exposed to SARS-CoV-2 infection and some interactions involving virus, tumor, host immune system and anticancer therapies are probably related to the poorer prognosis observed in those COVID-19 patients. Moreover, vaccination stands out as the main prevention method against severe SARS-CoV-2 infection and some particularities have been observed regarding the seroconversion of vaccinated oncologic patients including those with gastrointestinal malignancies. In this minireview, we gather updated information regarding the influence of the pandemic in the diagnosis of gastrointestinal neoplasms, new recommendations for the management of gastrointestinal cancer patients, the occurrence of SARS-CoV-2 infection in those individuals and the scenario of the vaccination against the virus in that population.

Efficacy and impact of SARS-CoV-2 vaccination on cancer treatment for breast cancer patients: a multi-center prospective observational study

Purpose

Vaccination is an essential strategy to prevent infection in the SARS-CoV-2 pandemic. However, there are concerns about vaccine efficacy and the impact of vaccination on cancer treatment. Additionally, the emergence of novel variants may affect vaccination efficacy. This multi-center, prospective, observational study investigated the efficacy and impact of vaccination against SARS-CoV-2 variants on treatment among breast cancer patients in Japan.

Methods

Patients with breast cancer scheduled to be vaccinated with the SARS-CoV-2 vaccine from May to November 2021 were prospectively enrolled (UMIN000045527). They were stratified into five groups according to their cancer treatment: no treatment, hormone therapy, anti-human epidermal growth factor receptor (HER)2 therapy, chemotherapy, and cyclin-dependent kinase 4/6 (CDK4/6) inhibitor. Serum samples for assessing serological responses were collected before the first vaccination and after the second vaccination.

Results

Eighty-five breast cancer patients were included. The overall seroconversion rate after second vaccination was 95.3% and the lowest seroconversion rate was 81.8% in the patients under chemotherapy. The overall positivity rate of neutralizing antibodies against the wild-type, α, Δ, κ, and omicron variants were 90.2%, 81.7%, 96.3%, 84.1%, and 8.5%, respectively. Among the patients under chemotherapy or CDK4/6 inhibitors, various degrees of decreased neutralizing antibody titers against SARS-CoV-2 variants were observed. Withdrawal or reduction of systemic therapy because of vaccination was observed in only one patient.

Conclusion

Our data support SARS-CoV-2 vaccination for breast cancer patients. However, a reduction in neutralizing antibody titers was suggested during chemotherapy and CDK4/6 inhibitors, raising concerns about the impact on long-term infection prevention.

Immunogenicity and Safety of the BNT162b2 mRNA COVID-19 Vaccine in Patients with Melanoma Treated with Immunotherapy

Simple Summary

The efficacy and safety of the BNT126b2 vaccine against SARS-CoV-2 has not been thoroughly studied in cancer patients treated with immunotherapy. This research aims to investigate the efficacy and safety of the vaccine in patients with melanoma under immunotherapy; at the same time, through the immunophenotyping of T cells and myeloid cells of the peripheral blood, it will be possible to look for changes in the subpopulations of such cells after vaccinations. The results of the study help establish the efficacy and safety of the vaccine in this population, especially since a theoretical concern exists about the vaccine triggering irAEs.

Abstract

The BNT162b2 vaccine against SARS-CoV-2 has a proven efficacy and a favorable safety profile. In cancer patients under immunotherapy in the form of immune-checkpoint inhibitors (ICIs), the efficacy of the vaccine has not been thoroughly studied, while a theoretical concern has also been raised about triggering immune-related adverse events (irAEs) by the vaccine. We conducted a prospective, non-interventional study on the immunogenicity and safety of the BNT162b2 vaccine in patients with advanced or metastatic melanoma treated with ICIs. Blood samples were obtained 0–4 days before the first dose and 12–21 days after the second dose of the vaccine for the quantification of the SARS-CoV-2 anti-spike antibody using an ELISA and immunophenotyping of the T and myeloid cell subpopulations. The active recording of AEs for a two-month period was conducted. Forty patients were included in the study. All but one (97.3%) achieved seroconversion after two doses of the vaccine and no correlations of the antibody titers with any of the studied parameters (age, gender, stage and duration of the disease, type of ICI, previous treatment, etc.) were found. Moreover, no differences in the subpopulations of the T cells (including the T-regulatory cells) or the myeloid cells were found pre- and post-vaccination. All AEs were low-grade, while one case of arthritis exacerbation was noted. The seroconversion rate in the studied population was high and was comparable to that of healthy subjects, while no major safety issues were raised during the safety follow-up. Finally, no derangements in the subpopulations of T cells or myeloid cells were noted. This is the first study focusing on the immunogenicity, safety, and effect of anti-SARS-CoV-2 vaccines on the blood-cell immunophenotype status of patients with melanoma treated with ICIs.

Strong Response to SARS-CoV-2 Vaccine Additional Doses Among Patients With Inflammatory Bowel Diseases

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has disrupted health care and has resulted in high mortality rates.¹ Vaccination is an international priority to mitigate the risks of SARS-CoV-2. The initial trials for development of SARS-CoV-2 vaccines excluded individuals with immunocompromising conditions.².

Adverse events following immunization and psychological distress among cancer patients/survivors following vaccination against SARS-CoV-2 infection

Purpose

This study aims to describe the adverse events following immunization (AEFIs) of SARS-CoV-2 vaccination in cancer patients/survivors associated with their psychological distress.

Methods

A cross-sectional study was conducted to assess AEFIs after the receipt of SARS-CoV-2 vaccines in cancer patients/survivors attending a university hospital in Malaysia. Psychological distress was measured using the Hospital Anxiety and Depression Scale (HADS) before and after the first and second doses of COVID-19 vaccine.

Results

A total of 217 complete responses were received. Compared with before vaccination, both HADS Anxiety (HADS-A) and HADS Depression (HADS-D) scores were significantly reduced after the first and second dose of the SARS-CoV-2 vaccine. Most of the participants had mild-or-moderate systemic and local AEFIs, with the most common being pain at the injection site, tiredness, and headache for both the first and second doses of the vaccine. Positive correlations between the total AEFI score and HADS-A (r = 0.309, p < 0.001) and HADS-D (r = 0.214, p = 0.001) scores were observed after the first dose of the SARS-CoV-2 vaccine. Similarly, positive associations were observed between the total AEFI score and HADS-A (r = 0.305, p < 0.001) and HADS-D (r = 0.235, p < 0.001) scores after the second dose of the SARS-CoV-2 vaccine.

Conclusion

Mild-to-moderate AEFIs found in this study help address vaccine hesitancy in cancer patients/survivors. Receiving the SARS-CoV-2 vaccine had a positive effect on decreasing psychological distress in cancer patients/survivors. High severity of an AEFI was associated with higher anxiety and depressive symptoms.

Adverse drug reactions to the three doses of the severe acute respiratory syndrome coronavirus 2 (SARS-COV-2) mRNA-1273 vaccine in a cohort of cancer patients under active treatment of a tertiary hospital in Madrid, Spain

Background: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines efficacy and safety have been tested in phase 3 studies in which cancer patients were not included or were underrepresented. Methods: The objective of this study is to evaluate the safety profile of the mRNA-1273 vaccine across cancer patients and its relationship to patients' demographics. We selected from our records all 18-years or older solid cancer patients under active treatment vaccinated with the complete three-dose schedule mRNA-1273 vaccine whose adverse drug reactions (ADRs)  after each dose were recorded. Medical records were reviewed retrospectively to collect data between April 19, 2021, and December 31, 2021. Patients with documented previous infection by SARS-Cov-2 were excluded. Results: A total of 93 patients met the inclusion criteria. Local ADRs were reported more frequently after the first and second dose than after the third (41.9%, 43% and 31.1% of the patients respectively), while systemic ADRs followed the opposite pattern (16.1%, 34.4% and 52.6% of the patients respectively). We found a statistically significant association between sex and systemic adverse reactions after the third dose, p < 0.001 and between systemic adverse reactions after the second dose and systemic adverse reactions after the third dose, p = 0.001 A significant linear trend, p = 0.012, with a higher Eastern Cooperative Oncology Group (ECOG) score associated with a lower proportion of patients suffering from systemic side effects was found. Women had 5.79 times higher odds to exhibit systemic ADRs after the third dose (p=0.01) compared to males. Increasing age was associated with a decreased likelihood of exhibiting ADRs (p=0.016). Conclusion: The mRNA-1273 vaccine shows a tolerable safety profile. The likelihood of ADRs appears to be associated with gender and age. Its association with ECOG scores is less evident. Further studies are needed to elucidate this data in cancer patients.

Antibody responses and risk factors associated with impaired immunological outcomes following two doses of BNT162b2 COVID-19 vaccination in patients with chronic pulmonary diseases

Introduction

Responses to COVID-19 vaccination in patients with chronic pulmonary diseases are poorly characterised. We aimed to describe humoral responses following two doses of BNT162b2 mRNA COVID-19 vaccine and identify risk factors for impaired responses.

Methods

Prospective cohort study including adults with chronic pulmonary diseases and healthcare personnel as controls (1:1). Blood was sampled at inclusion, 3 weeks, 2 and 6 months after first vaccination. We reported antibody concentrations as geometric means with 95% CI of receptor binding domain (RBD)-IgG and neutralising antibody index of inhibition of ACE-2/RBD interaction (%). A low responder was defined as neutralising index in the lowest quartile (primary outcome) or RBD-IgG <225 AU/mL plus neutralising index <25% (secondary outcome), measured at 2 months. We tested associations using Poisson regression.

Results

We included 593 patients and 593 controls, 75% of all had neutralising index ≥97% at 2 months. For the primary outcome, 34.7% of patients (n=157/453) and 12.9% of controls (n=46/359) were low responders (p<0.0001). For the secondary outcome, 8.6% of patients (n=39/453) and 1.4% of controls (n=5/359) were low responders (p<0.001). Risk factors associated with low responder included increasing age (per decade, adjusted risk ratio (aRR) 1.17, 95% CI 1.03 to 1.32), Charlson Comorbidity Index (per point) (aRR 1.15, 95% CI 1.05 to 1.26), use of prednisolone (aRR 2.08, 95% CI 1.55 to 2.77) and other immunosuppressives (aRR 2.21, 95% CI 1.65 to 2.97).

Discussion

Patients with chronic pulmonary diseases established functional humoral responses to vaccination, however lower than controls. Age, comorbidities and immunosuppression were associated with poor immunological responses.

Impaired serological response to COVID-19 vaccination following anti-cancer therapy: a systematic review and meta-analysis

Owing to the high coronavirus disease 2019 (COVID‐19)‐related morbidity and fatality rate among patients with cancer, the introduction of COVID‐19 vaccines is of profound significance in this fragile population. Accumulating data suggested that oncologic patients, especially those with anticancer therapy have an impaired immune response to COVID‐19 vaccination. However, the exact effect of anticancer treatments on postvaccination response has not been elucidated yet. We, therefore, conducted a meta‐analysis to evaluate the impact of treatments on response to COVID‐19 vaccination in patients with cancer. A total of 39 studies were finally included comprising 11 075 oncologic patients. Overall, we found the humoral response was significantly decreased in patients undergoing anticancer treatments (odds ratio [OR] = 2.55, 95% confidence interval [CI]: 2.04–3.18) compared with those without active treatment. The seroconversion rates were significantly lower in patients with chemotherapy (OR = 3.04, 95% CI: 2.28–4.05), targeted therapy (OR = 4.72, 95% CI: 3.18–7.01) and steroid usage (OR = 2.19, 95% CI: 1.57–3.07), while there was no significant association between immunotherapy or hormonal therapy and seroconversion after vaccination. Subgroup analyses showed therapies with anti‐CD20 antibody (OR = 11.28, 95% CI: 6.40–19.90), B‐cell lymphoma 2 inhibitor (OR = 5.76, 95% CI: 3.64–9.10), and Bruton tyrosine kinase inhibitor (OR = 6.86, 95% CI: 4.23–11.15) were significantly correlated with the risk of negative humoral response to vaccination. In conclusion, our results demonstrated that specific oncologic therapies may significantly affect serological response to COVID‐19 vaccines in patients with cancer. Thus, an adapted vaccination strategy taking the influence of active treatment into account is in need, and further research on the effect of the third dose of vaccine and the role of postvaccination cellular response in oncologic patients is also needed.

Booster doses of COVID-19 vaccines for patients with haematological and solid cancer: a systematic review and individual patient data meta-analysis

Importance

Patients with cancer have an increased risk of severe disease and mortality from COVID-19, as the disease and antineoplastic therapy cause reduced vaccine immunogenicity. Booster doses have been proposed to enhance protection, and efficacy data are emerging from several studies.

Objective

To evaluate the proportion of COVID-19 primary vaccination non-responders with cancer who seroconvert after a booster dose.

Methods

PubMed, EMBASE, CENTRAL and medRxiv were searched from 1st January 2021 to 10th March 2022. Quality was assessed using the Joanna Briggs Institute Critical Appraisal checklist.

Results

After the eligibility assessment, 22 studies were included in this systematic review and 17 for meta-analysis of seroconversion in non-responders, pooling a total of 849 patients with haematological cancer and 82 patients with solid cancer. Haematological cancer non-responders exhibited lower seroconversion at 44% (95% CI 36–53%) than solid cancer at 80% (95% CI 69–87%). Individual patient data meta-analysis found the odds of having a meaningful rise in antibody titres to be significantly associated with increased duration between the second and third dose (OR 1.02, 95% CI 1.00–1.03, P ≤ 0.05), age of patient (OR 0.960, 95% CI 0.934–0.987, P ≤ 0.05) and cancer type. With patients with haematological cancer as a reference, patients with lung cancer had 16.8 times the odds of achieving a meaningful increase in antibody titres (OR 16.8, 95% CI 2.95–318, P ≤ 0.05) and gastrointestinal cancer patients had 25.4 times the odds of achieving a meaningful increase in antibody titres (OR 25.4, 95% CI 5.26–492.21, P ≤ 0.05).

Conclusions

administration of a COVID-19 vaccine booster dose is effective in improving seroconversion and antibody levels. Patients with haematological cancer consistently demonstrate poorer response to booster vaccines than patients with solid cancer.

Predictors of poor serologic response to COVID-19 vaccine in patients with cancer: a systematic review and meta-analysis

Backgrounds

Patients with cancer presented a lower probability to obtain seroconversion after a complete course of COVID-19 vaccination. However, little was known on the factors that predict poor seroconversion in this frail population.

Methods

We searched the PubMed, EMBASE, and China National Knowledge Infrastructure databases for all articles within a range of published years from 2019 to 2022 on the predictors of response to COVID-19 vaccine in patients with cancer (last search was updated on 2st March 2022). The odds ratio corresponding to the 95% confidence interval was used to assess the outcome. The statistical heterogeneity among studies was assessed with the Q-test and I² statistics. The review was registered with PROSPERO (CRD42022315687) and reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.

Results

Twenty cohort studies met the inclusion criteria for this study, with 5,499 patients with cancer. We found that advanced age, male patients, and metastatic disease increased negative seropositivity to COVID-19 vaccine. Immunoglobulin heavy chain variable mutation status, high concentration of Ig G, Ig M, and Ig A were correlated with seropositivity. Relating to cancer treatment strategy, anti-CD20 therapy within recent 12 months and chemotherapy were negatively correlated with seroconversion. Meta-analysis found no significant difference associated with targeted treatment, immunotherapy, and endocrine treatment.

Conclusions

Our meta-analysis assessed the factors that predict poor seroconversion in order to plan better prevention strategies in this frail population. The results proposed that enhanced vaccination strategies would be beneficial for the special patients such as advanced male, or patients receiving active chemotherapy, and carefully prevention should be emphasised even after a complete course of vaccination.

COVID-19 vaccines in patients with cancer: immunogenicity, efficacy and safety

Patients with cancer have a higher risk of severe coronavirus disease (COVID-19) and associated mortality than the general population. Owing to this increased risk, patients with cancer have been prioritized for COVID-19 vaccination globally, for both primary and booster vaccinations. However, given that these patients were not included in the pivotal clinical trials, considerable uncertainty remains regarding vaccine efficacy, and the extent of humoral and cellular immune responses in these patients, as well as the risks of vaccine-related adverse events. In this Review, we summarize the current knowledge generated in studies conducted since COVID-19 vaccines first became available. We also highlight critical points that might affect vaccine efficacy in patients with cancer in the future.

Seropositivity and neutralising antibodies at six months after BNT162b2 vaccination in patients with solid tumours

Aim

Patients with cancer are at an increased risk for severe coronavirus disease of 2019. We previously reported initial findings from a single centre prospective study evaluating antibody response after BNT162b2 vaccine, showing that adequate antibody response was achieved after two doses, but not after one, in patients with cancer vaccinated during anticancer therapy. Herein, we report a follow-up study, evaluating antibody response six months after the second vaccine dose.

Methods

The study included patients with solid tumours undergoing anticancer treatment, and immunocompetent health-care workers serving as controls. Serum titres of the receptor-binding domain (RBD) IgG and neutralising antibodies (Nabs) were measured approximately six months after the second vaccine dose. Complete blood count values were collected and evaluated as predictors for antibody response.

Results

The analysis included 93 patients with cancer (66.7% metastatic). Six months after the second vaccine dose (mean 176 ± 20 days), seropositivity rate among patients and controls was 83.9% versus 96.3% (p = 0.0001), respectively. Median RBD-IgG titre was lower among patients compared with controls (2.3 versus 3.2, p = 0.0002). Among seropositive individuals, median Nabs titre was similar between patients with cancer and controls (p = 0.566). Among patients with cancer, lymphocyte and neutrophil counts were not correlated with either RBD-IgG or Nabs titres.

Conclusions

Seropositivity rates and RBD-IgG titre at six months after second BNT162b2 vaccine dose are lower among patients with cancer compared with healthy controls. However, Nabs titre is similar, suggesting a comparable protection among seropositive individuals. Lymphocyte count is not predictive of antibody response.

Attitudes towards and safety of the SARS-CoV-2 inactivated vaccines in 188 patients with systemic lupus erythematosus: a post-vaccination cross-sectional survey

Vaccination is key in mastering the COVID-19 pandemic. Data on attitudes towards and safety of the SARS-CoV-2 inactivated vaccines in patients with systemic lupus erythematosus (SLE) are limited. A post-vaccination cross-sectional survey was conducted to obtain data on attitudes towards and safety of the SARS-CoV-2 inactivated vaccines in SLE patients compared to healthy controls. A post-vaccination cross-sectional survey was conducted in 188 patients with SLE and in 190 healthy controls who had received at least one dose of SARS-CoV-2 inactivated vaccine to find out post-vaccination adverse event (AE) or SLE flares. A total of 188 patients with SLE and 190 healthy controls vaccinated with the two-dose regimen SARS-CoV-2 inactivated vaccine were enrolled in the study. The two groups were matched in age, sex, medical background, income, and education level. All the SLE patients were in disease remission or with low disease activity with a median age of 35 years, a sex constituent ratio of 87.4% female, and a median disease duration of 4 years. SLE patients had much more concerns about vaccination safety (44.7% vs. 15.8%, P < 0.001), and were much less willing to get vaccinated (57.4% vs. 88.4%, P < 0.001). SLE patients had more mild adverse events after the first vaccine dose (43.6% vs. 25.3%, P = 0.008), and less mild adverse events after the second vaccine dose (19.8% vs. 34.9%, P = 0.024), compared with healthy controls. The AEs were minor and there were no serious or major adverse events in both groups. In patients with SLE, the post-vaccination disease activity remained stable. One previously undiagnosed female progressed into symptomatic SLE after one week of vaccination. Although SLE patients had concerns about the safety of the SARS-CoV-2 vaccines, the inactivated vaccination was safe in patients with stable SLE.

COVID-19 Vaccination in Patients With Malignancy; A Systematic Review and Meta-Analysis of the Efficacy and Safety

Background

Data on the efficacy and safety of COVID-19 vaccines in patients with malignancy are immature. In this paper, we assessed the literature involving the use of COVID-19 vaccines in cancer patients and reported the seroconversion rates as the main outcome and severity of COVID-19 infection and side effects following COVID-19 vaccination as the secondary outcomes.

Methods

A systematic review with meta-analysis was performed. Searches were conducted in electronic websites, databases, and journals, including Scopus, PubMed, Embase, and Web of Science from January 01, 2019, to November 30, 2021. Studies reporting data on the safety and efficacy of COVID vaccine in cancer patients using any human samples were included. The risk of bias was assessed using the NEWCASTLE-OTTAWA scale in the included studies.

Results

A total of 724 articles were identified from databases, out of which 201 articles were duplicates and were discarded. Subsequently, 454 articles were excluded through initial screening of the titles and abstracts. Moreover, 41 studies did not report the precise seroconversion rate either based on the type of cancer or after injection of a second dose of COVID vaccine. Finally, 28 articles met all the inclusion criteria and were included in this systematic review. The overall seroconversion rates after receiving a second dose of COVID-19 vaccine, based on type of cancer were 88% (95% CI, 81%-92%) and 70% (95% CI, 60%-79%) in patients with solid tumors and hematologic malignancies, respectively.

Conclusion

Overall, we conclude that vaccination against COVID-19 in patients with active malignancies using activated and inactivated vaccines is a safe and tolerable procedure that is also accompanied by a high efficacy.

Parallel evolution and differences in seroprevalence of SARS-CoV-2 antibody between patients with cancer and health care workers in a tertiary cancer centre during the first and second wave of COVID-19 pandemic: canSEROcov-II cross-sectional study

Background

Patients with cancer are a population at high risk of severe infection from SARS-CoV-2. Patients with cancer regularly attend specialised healthcare centres for management and treatment, where they are in contact with healthcare workers (HCWs). Numerous recommendations target both patients with cancer and HCWs to minimise the spread of SARS-CoV-2 during these interactions.

Objective

To investigate the parallel evolution of the COVID-19 epidemic in these 2 populations over time, we studied the seroprevalence of anti-SARS-CoV-2 antibodies after both the first and second waves of the pandemic, and in both cancer patients and HCWs from a single specialised anti-cancer centre. Factors associated with seropositivity were identified in both populations.

Methods

We conducted a cross-sectional study after the second wave of the COVID pandemic in France. All participants were invited to undergo serological testing for SARS-CoV-2 and complete a questionnaire collecting data about their working conditions (for HCWs) or medical management (for patients) during this period. Results after the second wave were compared to those of a previous study among 1011 patients with cancer and 663 HCWs performed in the same centre after the first wave, using the same evaluations.

Findings

We included 502 HCWs and 507 patients with cancer. Seroprevalence of anti-SARS-CoV-2 antibodies was higher after the second wave than after the first wave in both HCWs (15.1% versus 1.8%; p < 0.001), and patients (4.1% versus 1.7%; p = 0.038). By multivariate analysis, the factors found to be associated with seropositivity after the second wave for HCWs were: working in direct patient care (p = 0.050); having worked in a dedicated COVID-19 unit (p = 0.0036); contact with a person with COVID-19-positive in the workplace (p = 0.0118) or outside of the workplace (p = 0.0297). Among patients with cancer, only a contact with someone who tested positive for COVID-19 was found to be significantly associated with positive serology. The proportion of reported contacts with individuals with COVID-19-positive was significantly lower among patients with cancer than among HCWs (7.6% versus 40.7%, respectively; p < 0.0001)

Interpretation

Between the first and second waves of the epidemic in France, the seroprevalence of anti-SARS-CoV-2 antibodies increased to a lesser extent among patients with cancer than among their HCWs, possibly due to better self-protection, notably social distancing. The risk factors for infection identified among HCWs plead in favour of numerous intra-hospital contaminations, especially for HCWs in contact with high-risk patients. This underlines the compelling need to pursue efforts to implement strict hygiene and personal protection measures (including vaccination) to protect HCWs and patients with cancer.

Third dose of anti-SARS-CoV-2 vaccine for patients with cancer: Should humoral responses be monitored? A position article

Taking into account higher risk of severe coronavirus disease 2019 or death among patients with cancer, as well as impaired immunogenicity after anti-SARS-CoV-2 vaccines, in addition to waning immunity, booster dosing appears mandatory in this patient population. This review sought to provide reasonable evidence so as to assist oncologists in their daily practice, helping them decide when an anti-SARS-Cov2 antibody (Ab) dosage should be scheduled after a full two-dose vaccination and, if necessary, propose an early third dose (D3). Such D3 could apply to non-responder patients with anti-Spike (S) Abs titres <40 binding Ab unit (BAU)/mL. For lowresponder patients with anti-S Ab titres between 40 BAU/mL and 100/260 BAU/mL (suggested area of uncertainty), an early D3 may similarly be proposed. Nevertheless, this D3 could be administered in a less urgent manner, taking into account associated comorbidities and regional epidemic incidence rates. This latter strategy may comprise a monthly dosage of anti-S titres so as to better assess the kinetics of waning immunity. For responder patients with anti-S titres above 260 BAU/mL, we suggest to follow the recommendations outlined for the general population. Given this context, patients with anti-S titres above 1000 BAU/mL should be given the possibility to undergo anti-S titre control after three months, designed to assess rapid humoral waning immunity. We strongly recommend that patients with cancer be included into observational serological monitoring studies or clinical trials that are dedicated to severe immunocompromised patients without any humoral seroconversion after D3.

Recent advances in nanotechnology-based COVID-19 vaccines and therapeutic antibodies

COVID-19 has caused a global pandemic and millions of deaths. It is imperative to develop effective countermeasures against the causative viral agent, SARS-CoV-2 and its many variants. Vaccines and therapeutic antibodies are the most effective approaches for preventing and treating COVID-19, respectively. SARS-CoV-2 enters host cells through the activities of the virus-surface spike (S) protein. Accordingly, the S protein is a prime target for vaccines and therapeutic antibodies. Dealing with particles with dimensions on the scale of nanometers, nanotechnology has emerged as a critical tool for rapidly designing and developing safe, effective, and urgently needed vaccines and therapeutics to control the COVID-19 pandemic. For example, nanotechnology was key to the fast-track approval of two mRNA vaccines for their wide use in human populations. In this review article, we first explore the roles of nanotechnology in battling COVID-19, including protein nanoparticles (for presentation of protein vaccines), lipid nanoparticles (for formulation with mRNAs), and nanobodies (as unique therapeutic antibodies). We then summarize the currently available COVID-19 vaccines and therapeutics based on nanotechnology.

Persistence of Anti-SARS-CoV-2 Antibodies in Long Term Care Residents Over Seven Months After Two COVID-19 Outbreaks

Background

As part of the public health outbreak investigations, serological surveys were carried out following two COVID-19 outbreaks in April 2020 and October 2020 in one long term care facility (LTCF) in British Columbia, Canada. This study describes the serostatus of the LTCF residents and monitors changes in their humoral response to SARS-CoV-2 and other human coronaviruses (HCoV) over seven months.

Methods

A total of 132 serum samples were collected from all 106 consenting residents (aged 54-102) post-first outbreak (N=87) and post-second outbreak (N=45) in one LTCF; 26/106 participants provided their serum following both COVID-19 outbreaks, permitting longitudinal comparisons between surveys. Health-Canada approved commercial serologic tests and a pan-coronavirus multiplexed immunoassay were used to evaluate antibody levels against the spike protein, nucleocapsid, and receptor binding domain (RBD) of SARS-CoV-2, as well as the spike proteins of HCoV-229E, HCoV-HKU1, HCoV-NL63, and HCoV-OC43. Statistical analyses were performed to describe the humoral response to SARS-CoV-2 among residents longitudinally.

Findings

Survey findings demonstrated that among the 26 individuals that participated in both surveys, all 10 individuals seropositive after the first outbreak continued to be seropositive following the second outbreak, with no reinfections identified among them. SARS-CoV-2 attack rate in the second outbreak was lower (28.6%) than in the first outbreak (40.2%), though not statistically significant (P>0.05). Gradual waning of anti-nucleocapsid antibodies to SARS-CoV-2 was observed on commercial (median Δ=-3.7, P=0.0098) and multiplexed immunoassay (median Δ=-169579, P=0.014) platforms; however, anti-spike and anti-receptor binding domain (RBD) antibodies did not exhibit a statistically significant decline over 7 months. Elevated antibody levels for beta-HCoVs OC43 (P<0.0001) and HKU1 (P=0.0027) were observed among individuals seropositive for SARS-CoV-2 compared to seronegative individuals.

Conclusion

Our study utilized well-validated serological platforms to demonstrate that humoral responses to SARS-CoV-2 persisted for at least 7 months. Elevated OC43 and HKU1 antibodies among SARS-CoV-2 seropositive individuals may be attributed to cross reaction and/or boosting of humoral response.