Immunogenicity of SARS-CoV-2 Vaccine in Dialysis

SARS-CoV-2 Vaccine Effectiveness and Breakthrough Infections Among Patients Receiving Maintenance Dialysis

RATIONALE & OBJECTIVE

SARS-CoV-2 vaccine effectiveness and immunogenicity threshold associated with protection against COVID-19-related hospitalization or death in the dialysis population are unknown.

STUDY DESIGN

Retrospective, observational study.

SETTING & PARTICIPANTS

Adult patients without COVID-19 history receiving maintenance dialysis through a national dialysis provider and treated between February 1 and December 18, 2021, with follow-up through January 17, 2022.

PREDICTOR

SARS-CoV-2 vaccination status.

OUTCOMES

All SARS-CoV-2 infections, composite of hospitalization or death following COVID-19.

ANALYTICAL APPROACH

Logistic regression was used to determine COVID-19 case rates and vaccine effectiveness.

RESULTS

Of 16,213 patients receiving dialysis during the study period, 12,278 (76%) were fully vaccinated, 589 (4%) were partially vaccinated, and 3,346 (21%) were unvaccinated by the end of follow-up. Of 1,225 COVID-19 cases identified, 550 (45%) occurred in unvaccinated patients, and 891 (73%) occurred during the Delta variant-dominant period. Between the pre-Delta period and the Delta-dominant period, vaccine effectiveness rates against a severe COVID-19-related event (hospitalization or death) were 84% and 70%, respectively. In the subset of 3,202 vaccinated patients with at least one anti-spike immunoglobulin G (IgG) assessment, lower anti-spike IgG levels were associated with higher case rates per 10,000 days and higher adjusted hazard ratios for infection and COVID-19-related hospitalization or death.

LIMITATIONS

Observational design, residual biases, and confounding may exist.

CONCLUSIONS

Among maintenance dialysis patients, SARS-CoV-2 vaccination was associated with a lower risk of COVID-19 diagnosis and associated hospitalization or death. Among vaccinated patients, a low anti-spike IgG level is associated with worse COVID-19-related outcomes.

Waning Humoral Response 6 Month after Double Vaccination with the mRNA-BNT162b2 Vaccine in Hemodialysis Patients

Introduction

Although most hemodialysis patients (HDP) exhibit an initial seroresponse to vaccination against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), studies have shown this response to be lower compared to healthy subjects. This fact raised concerns regarding the durability of the immune response and effective protection against severe Coronavirus disease 2019 (COVID-19) in this vulnerable population. The aim of our study was to evaluate the change in antibody levels over time in HDP population.

Materials and Methods

We performed a prospective multicenter study, evaluating antibody response among HDP at 2 and at 6 months after complete two-dose vaccination course with the mRNA-BNT162b2 (Pfizer-BioNTech) vaccine. The study was performed in 14 hemodialysis units of a private dialysis provider in Lithuania. The serum samples of 189 HDP were tested for SARS-CoV-2 IgG against the Spike glycoprotein.

Results

189 HDP participated in the study. Patients were 64.3±15.7 years of age, 116 (61.4%) were males and 73 (38.6%) were females. Among them, 183 (96.8%) were seropositive for anti-S IgG at 2 months after the second immunization dose. Six months after the second dose only 145 (76.7%) of study participants had positive anti-S IgG titers. The median level of anti-S IgG titers after 2 months was 383.1 BAU/mL (166.2-995.6) and after 6 months this level significantly decreased to 51.4 BAU/mL (22.0-104.0) (p<0.001). Seroresponses at both time points inversely correlated with increasing patient's age. Risk factor for absent response after 2 months included oncologic disease. Systemic autoimmune disease and a history of myocardial infarction increased risk to be seronegative 6 months after the second vaccine dose.

Conclusions

The majority of hemodialysis patients seroresponded after BNT162b2/Pfizer vaccination, but vaccine-induced humoral immunity wanes over time.

Comparison of COVID-19 Inactivated Virus Vaccine Immunogenicity Between Healthy Individuals and Patients on Hemodialysis: A Single-Center Study From Pakistan

Introduction

This study compares the immune response after coronavirus disease 2019 (COVID-19) inactivated virus vaccine between healthy individuals (HI) and patients on hemodialysis (HD).

Methods

In this cross-sectional, comparative study, the presence or absence of immunoglobulin G (IgG) anti-S antibody and IgG anti-S antibody titer was compared between HI, and patients on HD after two doses of COVID-19 vaccine.

Results

A total of 81 participants, 50 (61.7%) HD patients and 31 (38.3%) HI, were studied. The mean age was 52.9±12 in HD patients and 42±12.4 in HI. Vaccination responder rates were 80.6% in HI and 72% in HD patients after the first dose (p=0.38) and 93.5% in HI and 94% in HD at the third week of the second dose of the vaccine (p=0.93). The mean IgG antibody titer was 156.3±113.8 in HI and 143.4 ± 117.8 in HD patients (p=0.538) after the first dose and 186.7 ± 97.9 in HI and 180.6 ± 105.8 in HD patients (p=0.552) at three weeks of the second dose. No statistically significant difference was found in antibody titer with respect to gender, age, vaccine (BBIBP-CorV or Conovac), and hypertension. Diabetic HD patients had a lower antibody titer than non-diabetic HD patients (p=0.03) while participants who had a history of COVID-19 infection had a higher IgG titer (p = 0.001). The levels of IgG titer in the same patient increased, corresponding to the doses of vaccine (p <0.001). No HD patient developed COVID-19 infection till the third week of vaccination.

Conclusion

This study demonstrates a similar humoral response after COVID-19 inactivated virus vaccination in HD patients and HI. The response was lower among diabetic patients on HD and better in those with previous COVID-19 infection.

Immunogenicity and Safety of COVID-19 Vaccines in Patients Receiving Renal Replacement Therapy: A Systematic Review and Meta-Analysis

Background

Systematic data on the efficacy and safety of COVID-19 vaccine in patients on renal replacement therapy (RRT) remains limited. We conducted a meta-analysis on the efficacy and safety of COVID-19 vaccine in patients on RRT.

Methods

Eligible studies were identified by systematic literature search in four electronic databases. Twenty-seven studies (4,264 patients) were included for meta-analysis. 99% patients received mRNA vaccine.

Results

Patients on RRT showed inferior seropositivity after two-dosed COVID-19 vaccine, 44% lower than the general population. Kidney transplant recipients (KTRs) had significantly lower seropositivity than patients on haemodialysis (HD) or peritoneal dialysis (PD) (26.1 vs. 84.3% and 92.4% respectively, p < 0.001 for both). Compared with healthy controls, KTRs, HD and PD patients were 80% (95% CI: 62–99%), 18% (95% CI: 9–27%) and 11% (95% CI: 1–21%) less likely to develop antibodies after vaccination (p < 0.001, <0.001 and 0.39 respectively). In KTRs, every 1% increase in using mycophenolate was associated with 0.92% reduction in seropositivity (95% CI: −1.68, −0.17, p = 0.021) at population level. The overall adverse event rate attributed to vaccination was 2.1%. Most events were mild.

Conclusion

Patients on RRT, particularly KTRs, had significantly reduced antibody response after two-dosed COVID-19 vaccination. Vaccination is generally well tolerated.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/, identifier: CRD42021261879.

Negative immune responses to two-dose mRNA COVID-19 vaccines in renal allograft recipients assessed with simple antibody and interferon gamma release assay cellular monitoring

Studies are urgently needed to characterize immunogenicity, efficacy, and safety of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) mRNA vaccines in kidney transplant (KT) recipients, excluded from major clinical trials. Complex ELISPOT and other cellular response techniques have been applied, but simpler tools are needed. An easy-to-use real-world monitoring of SARS-CoV-2 IgG antibodies against the Spike protein and QuantiFERON^® SARS-CoV-2 IFNγ release assay (IGRA) were performed at baseline and 28 days after the second dose in KT recipients and controls (dialysis patients and healthy ones). All healthy controls and >95% dialysis controls became positive for anti-S IgG antibodies, while only 63.3% of KT patients seroconverted with a very low antibody level. A positive IGRA was documented in 96.9% of controls, 89.3% peritoneal dialysis, 77.6% hemodialysis, 61.3% of KT patients transplanted more than 1 year ago and only 36% of those transplanted within the previous 12 months. Overall, 100% of healthy controls, 95.4% of dialysis patients and 78.8% KT recipients developed any immune response (humoral and/or cellular) against SARS-CoV-2. KT patients showed low rates of immune responses to mRNA Coronavirus infectious disease 2019 vaccines, especially those with recent transplantations. Simple humoral and cellular monitoring is advisable, so that repeated doses may be scheduled according to the results.

Longitudinal Analysis of Antibody Responses to the mRNA BNT162b2 Vaccine in Patients Undergoing Maintenance Hemodialysis: A 6-Month Follow-Up

Background: Patients on hemodialysis (HD) are at higher risk for COVID-19, overall are poor responders to vaccines, and were prioritized in the Portuguese vaccination campaign. Objective: This work aimed at evaluating in HD patients the immunogenicity of BTN162b2 after the two doses induction phase, the persistence of specific antibodies along time, and factors predicting these outcomes. Methods: We performed a prospective, 6-month long longitudinal cohort analysis of 156 HD patients scheduled to receive BTN162b2. ELISA quantified anti-spike IgG, IgM, and IgA levels in sera were collected every 3 weeks during the induction phase (t0 before vaccine; t1, d21 post first dose; and t2 d21 post second dose), and every 3-4 months during the waning phase (t3, d140, and t4, d180 post first dose). The age-matched control cohort was similarly analyzed from t0 to t2. Results: Upon exclusion of participants identified as previously exposed to SARS-CoV-2, seroconversion at t1 was lower in patients than controls (29 and 50%, respectively, p = 0.0014), while the second vaccine dose served as a boost in both cohorts (91 and 95% positivity, respectively, at t2, p = 0.2463). Lower response in patients than controls at t1 was a singularity of the participants ≤ 70 years (p = 2.01 × 10-05), associated with immunosuppressive therapies (p = 0.013), but not with lack of responsiveness to hepatitis B. Anti-spike IgG, IgM, and IgA levels decreased at t3, with IgG levels further waning at t4 and resulting in >30% seronegativity. Anti-spike IgG levels at t1 and t4 were correlated (ρ = 0.65, p < 2.2 × 10-16). Conclusions: While most HD patients seroconvert upon 2 doses of BNT162b2 vaccination, anti-spike antibodies levels wane over the following 4 months, leading to early seroreversion in a sizeable fraction of the patients. These findings warrant close monitoring of COVID-19 infection in vaccinated HD patients, and advocate for further studies following reinforced vaccination schedules.

Antibody Response and Safety After mRNA-1273 SARS-CoV-2 Vaccination in Peritoneal Dialysis Patients - the Vienna Cohort

Background

Dialysis patients are at high risk for a severe clinical course after infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Safety and early immune responses after mRNA-based vaccination have been reported mostly in patients on hemodialysis (HD), whereas reports of peritoneal dialysis (PD) patients remain rare.

Methods

In this retrospective observational study, 39 PD patients had received two doses of the mRNA-1273 Moderna^® vaccine. We analyzed SARS-CoV-2 Spike (S) antibody titers 4 weeks after each dose of mRNA-1273 and report local and systemic side effects in PD patients that occurred within one week after each mRNA-1273 dose. Using a quantile regression model we examined factors that might influence SARS-CoV-2 S antibody levels in PD patients.

Results

Four weeks after the first dose of mRNA-1273 vaccine 33 of 39 (84.6%) PD patients seroconverted and presented with 6.62 U/mL (median; IQR 1.57-22.5) anti-SARS-CoV-2 S antibody titers. After the second dose, 38 of 39 (97.4%) PD patients developed anti-SARS-CoV-2 S antibodies and titers increased significantly (median 968 U/mL; IQR 422.5-2500). Pain at the injection site was the most common local adverse event (AE) (71%). Systemic AEs occurring after the first dose were mostly fatigue (33%) and headache (20%). No severe systemic AEs were reported after the first injection. After the second dose the incidence and the severity of the systemic AEs increased. The most common systemic AEs were: fatigue (40.5%), headache (22.5%), joint pain (20%), myalgia (17.5%) and fever (13%). Lower Davies Comorbidity Score (p=0.04) and shorter dialysis vintage (p=0.017) were associated with higher antibody titers after the first dose. Patients with higher antibody titers after the first dose tended to have higher antibody titers after the second dose (p=1.53x10^-05).

Conclusions

Peritoneal dialysis patients in this cohort had a high seroconversion rate of 97.4%, showed high antibody titers after full vaccination and tolerated the anti-SARS-CoV-2 mRNA-1273 vaccine well without serious adverse events.

COVID-19 Vaccines in Patients with Maintenance Hemodialysis

The COVID-19 pandemic has infected more than 180 million people and caused more than 3.95 million deaths worldwide. In addition to personal hygiene, augmented cleaning, social distancing, and isolation, vaccine development and immunization are essential for this highly contagious disease. Patients with maintenance hemodialysis (MHD) have a greater risk of COVID-19 infection owing to their comorbidities, defective immunity, and repeated crowded in-center dialysis settings. However, many patients hesitate to get vaccinated because of their misunderstandings. The Efficacy of COVID-19 vaccination has been intensively discussed in the general population, whereas the data concerning the effectiveness of vaccination in MHD patients are relatively scanty. Nevertheless, those limited publications can provide some valuable information. Overall, lower and more delayed antibody responses following COVID-19 vaccination were observed in patients with MHD than in healthy controls in the settings of different populations, vaccines and dosage, definitions of the immune response, and antibody detection timepoints. Younger age, previous COVID-19 infection, and higher serum albumin level were positively associated with antibody formation, whereas older age and receiving immunosuppressive therapy were unfavorable factors. However, it remains uncertain between the elicited antibodies following vaccination and the genuine protection against COVID-19 infection. Patients with MHD should make their COVID-19 vaccination a priority in addition to other protective measures. More studies focusing on different vaccines, non-humoral immune responses, and risk-benefit analyses are warranted.

Antibody Response to COVID-19 vaccination in Patients Receiving Dialysis

Background

Patients receiving dialysis may mount impaired responses to COVID19 vaccination.

Methods

We report antibody response to vaccination from 1140 patients without, and 493 patients with pre-vaccination SARS-CoV-2 RBD antibody. We used commercially available assays (Siemens) to test remainder plasma monthly in association with vaccination date and type, and assess prevalence of absent total receptor binding antibody, and absent or attenuated (index value < 10) semiquantitative receptor binding domain IgG index values. We used Poisson regression to evaluate risk factors for absent or attenuated response to vaccination.

Results

Among patients who were seronegative versus seropositive before vaccination, 62% and 56% were ≥65 years old, 20% and 24% were Hispanic, and 22% and 23% were Black. Median IgG index values rose steadily over time, and were higher among the seropositive than in the seronegative patients after completing vaccination (150 [25th, 75th percentile 23.2, 150.0] versus 41.6 [11.3, 150.0]). Among 610 patients who completed vaccination (assessed ≥14 days later, median 29 days later), the prevalence of absent total RBD response, and absent and attenuated semiquantitative IgG response was 4.4% (95% CI 3.1, 6.4%), 3.4% (2.4, 5.2%), and 14.3% (11.7, 17.3%) respectively. Risk factors for absent or attenuated response included longer vintage of end-stage kidney disease, and lower pre-vaccination serum albumin.

Conclusions

More than one in five patients receiving dialysis had evidence of an attenuated immune response to COVID19 vaccination.