Seroresponse to SARS-CoV-2 vaccines among maintenance dialysis patients over six months

Abstract

Background and Objectives: While most maintenance dialysis patients exhibit initial seroresponse to vaccination, concerns remain regarding the durability of this antibody response. This study evaluated immunity over time. Design, setting, participants, and measurements: This retrospective cohort study included maintenance dialysis patients from a midsize national dialysis provider who received a complete SARS-CoV-2 vaccine series and had at least one antibody titer checked after full vaccination. Immunoglobulin G spike antibodies (SAb-IgG) titers were assessed monthly with routine labs beginning after full vaccination and followed over time; the semiquantitative SAb-IgG titer reported a range between 0 and ≥20 U/L. Descriptive analyses compared trends over time by prior history of COVID-19 and type of vaccine received. Time-to-event analyses were conducted for the outcome of loss of seroresponse (SAb-IgG < 1 U/L or development of COVID-19). Cox proportional hazards regression was used to adjust for additional clinical characteristics of interest. Results: Among 1898 maintenance dialysis patients, 1567 (84%) had no prior history of COVID-19. Patients without a history of COVID-19 had declining titers over time. Among 441 BNT162b2/Pfizer recipients, median [IQR] SAb-IgG titer declined from 20 [5.99-20] U/L in month 1 to 1.30 [0.15-3.59] U/L by month 6. Among 779 mRNA-1273/Moderna recipients, median [IQR] SAb-IgG titer declined from 20 [20-20] in month 1 to 6.20 [1.74-20] by month 6. The 347 Ad26.COV2.S/Janssen recipients had a lower titer response than mRNA vaccine recipients over all time periods. In time-to-event analyses, Ad26.COV2.S/Janssen and mRNA-1273/Moderna recipients had the shortest and longest time to loss of seroresponse, respectively. The maximum titer reached in the first two months after full vaccination was predictive of the durability of the SAb-IgG seroresponse; patients with SAb-IgG titer 1-19.99 U/L were more likely to have loss of seroresponse compared to patients with SAb-IgG titer ≥20 U/L (HR 23.9 [95% CI: 16.1-35.5]). Conclusions: Vaccine-induced seroresponse wanes over time among maintenance dialysis patients across vaccine types. Early titers after full vaccination predict the durability of seroresponse.

Characterization of the significant decline in humoral immune response six months post-SARS-CoV-2 mRNA vaccination: A systematic review

“…While the Ab level needed for protection is not established yet, there is a correlation between seroimmunity and protection from infection as well as seroimmunity and the likelihood of transmission. 19 Therefore, this declining trend, with data demonstrating up to 95% decline in Ab levels depending on the antigenic target, supports the need for boosters and serologic monitoring moving forward to identify low responders and timely need for additional booster administration.…”

“…29,45 Moreover, the robustness of initial Ab response postvaccination is reported to predict rapidity of Ab titer decline. 19 Those with higher maximum Ab response within 2 months from full vaccination were less likely to become seronegative or develop SARS-CoV-2 infection. 19 As such, it is important to follow the course of Ab titers several weeks after full vaccination among those with stage-specific comorbidities in order to predict better when best to give additional booster vaccine doses and ensure appropriate protection.…”

SARS-CoV-2 vaccine effectiveness and breakthrough infections in maintenance dialysis patients

“…We recently showed that more than half of fully vaccinated patients' antibodies wane by 4-6 months, particularly among those whose initial response was not maximal based on our assay. 12 The association of low or undetectable antibody levels with breakthrough COVID-19 supports potential use of antibody levels for guiding vaccination practices, and routinely monitoring COVID-19 vaccine seroresponse via SAb-IgG levels may identify patients at risk for COVID-19 infection. A similar model already exists for maintenance dialysis patients with Hepatitis B antibody monitoring.…”

“…5,6,9 We previously reported that 10-15% of dialysis patients were non-responders to 2 doses of mRNA vaccines. 3,12 Recognizing this vulnerability, France authorized a third dose of SARS-CoV-2 mRNA vaccine for dialysis patients, 13 reporting that a third dose of BNT162b2/Pfizer vaccine promoted seroconversion in more than half of initially non-responding dialysis patients. 14 Breakthrough COVID-19 cases and COVID-19 related hospitalizations among fully vaccinated dialysis patients increased when delta variant became dominant, potentially superimposing a more virulent strain on waning immunity, as most dialysis patients were vaccinated March or earlier.…”

“…14 Breakthrough COVID-19 cases and COVID-19 related hospitalizations among fully vaccinated dialysis patients increased when delta variant became dominant, potentially superimposing a more virulent strain on waning immunity, as most dialysis patients were vaccinated March or earlier. 12 Vaccine type may be associated with breakthrough infections, with receipt of the Ad26.COV2.S/Janssen vaccine not only associated with lower antibody response, 12 but also with higher breakthrough and COVID-19 related hospitalization rates. Of note, the breakthrough COVID-19 case rate among fully vaccinated maintenance dialysis patients (1.6%) is higher than that reported for transplant patients (0.8%).…”