Analysis of mRNA COVID-19 Vaccine Uptake Among Immunocompromised Individuals in a Large US Health System

COVID-19 vaccine immunogenicity and safety surrounding fourth and subsequent vaccine doses in patients with hematologic malignancies

BACKGROUND

Immune response to COVID-19 vaccine is diminished in patients with hematologic malignancy. There is limited data regarding response to vaccine doses in these patients.

PURPOSE

To quantify the humoral immune response engendered by 4th and subsequent doses of SARS-CoV-2 vaccination as measured by anti-Spike (anti-S) antibody levels, based on dried blood spot (DBS) testing, in patients with hematologic malignancies. Anti-S binds to the spike protein of the SARS-CoV-2 virus and is indicative of vaccine immunogenicity.

METHODS

We conducted a prospective study of hematologic malignancies between August 2021 and January 2023 at 12 sites across Canada. Participants were followed longitudinally and submitted finger-prick DBS cards at set intervals associated with vaccination. Samples were processed via high throughput ELISA assay to detect serum antibodies against nucleocapsid (N) and spike (S) proteins.

RESULTS

We obtained 3071 samples on 790 unique patients. Of these, 372 unique participants with 1840 samples had anti-S results available post-4th, 5th or 6th COVID-19 vaccine dose and were included for analysis. Three hundred thirty-three patients of the 372 participants submitted a DBS sample post 4th dose. Of these, 257 patients (77.2%) had a positive anti-S antibody. A total of 198 patients had paired samples pre- and post-dose 4, of which 59 (29.7%) had a negative anti-S antibody pre-dose 4. Of these, 20 (33.4%) developed positive anti-S antibody post-dose 4. One hundred forty-nine patients submitted a DBS sample post-dose 5. Of these, 135 patients (90.6%) had positive anti-S antibody. A total of 52 had paired samples pre- and post-dose 5. Six (8.7%) had a negative anti-S antibody pre-dose 5, of which two (33.3%) developed positive anti-S antibody post-dose 5. Of these 372 patients, 123 (34%) reported COVID-19 infection and 4 (1%) had a COVID-19 related hospitalization. There were no reported deaths from COVID-19.

CONCLUSIONS

This prospective cohort study showed that humoral immune response improved with subsequent doses of COVID-19 vaccines.

Burden of COVID-19 variant omicron in immunocompromised patients in Spain: systematic review

After the COVID-19 pandemic, the omicron variant of the SARS-CoV-2 virus became the dominant lineage in Spain in 2022. Although it possesses a milder pathogenicity than previous variants, it still poses a high risk of causing severe COVID-19 for immunocompromised populations. A systematic review was conducted to assess the burden of COVID-19 in Spain among immunocompromised patients during the omicron predominance (1/04/2022-1/04/2023), using PubMed, Cochrane Library, and EPICOVIDEHA between May and July 2023. The search retrieved 217 articles, of which a total of 5 were included. Upon analysis, it was observed that immunocompromised patients during the omicron lineage predominance continue to exhibit higher rates of hospitalizations, ICU admissions, and mortality compared to the general population affected by COVID-19. Although the pandemic has ended, the risk persists for immunocompromised individuals.

Pharmacovigilance in Vaccines: Importance, Main Aspects, Perspectives, and Challenges-A Narrative Review

Pharmacovigilance plays a central role in safeguarding public health by continuously monitoring the safety of vaccines, being critical in a climate of vaccine hesitancy, where public trust is paramount. Pharmacovigilance strategies employed to gather information on adverse events following immunization (AEFIs) include pre-registration data, media reports, clinical trials, and societal reporting. Early detection of AEFIs during clinical trials is crucial for thorough safety analysis and preventing serious reactions once vaccines are deployed. This review highlights the importance of societal reporting, encompassing contributions from community members, healthcare workers, and pharmaceutical companies. Technological advancements such as quick response (QR) codes can facilitate prompt AEFI reporting. While vaccines are demonstrably safe, the possibility of adverse events necessitates continuous post-marketing surveillance. However, underreporting remains a challenge, underscoring the critical role of public engagement in pharmacovigilance. This narrative review comprehensively examines and synthesizes key aspects of virus vaccine pharmacovigilance, with special considerations for specific population groups. We explore applicable legislation, the spectrum of AEFIs associated with major vaccines, and the unique challenges and perspectives surrounding pharmacovigilance in this domain.

Clinical Features and Prognostic Predictors in Patients with Renal Transplant Complicated by SARS-CoV-2 Infection, a Retrospective Single-Center Study

Background

This study examines the clinical outcomes and prognostic factors of COVID-19 in renal transplant recipients. Given their immunosuppressed status, these patients are at higher risk of severe complications from COVID-19. The study aims to provide healthcare professionals with critical insights for diagnosing and managing this vulnerable population.

Patients and methods

This retrospective cohort study included adult renal transplant recipients diagnosed with COVID-19. Data on demographics, medical history, laboratory results, and patient outcomes were analyzed to identify clinical characteristics and prognostic factors.

Results

This study included 115 renal transplant recipients with COVID-19, predominantly male, with a mortality rate of 10.4% (12 deaths). The overall vaccination rate was 20%. Univariate analysis showed significant differences between survivors and non-survivors in initial serum creatinine levels, and percentages of neutrophils, monocytes, and lymphocytes, along with CRP levels on day 3. Additionally, CRP levels, hemoglobin, and platelet counts on day 7 also differed significantly. Multivariate analysis identified CRP levels on days 3 and 7, day 7 hemoglobin and platelet counts, and concurrent bacterial infections as independent risk factors for mortality.

Conclusion

Elevated CRP levels, renal impairment, and bacterial co-infections play a significant role in the outcomes of COVID-19 in kidney transplant recipients. This study highlights the importance of monitoring these factors for early identification and management of high-risk patients.

Humoral and cellular immune response in patients of liver cirrhosis and immunocompetent recipient of ChAdOx1nCoV-19 Vaccine (Covishield)

Despite the effectiveness of COVID-19 vaccination in reducing the severity of the disease, the demand for booster is increasing in vulnerable populations like elderly and immunocompromised individuals especially with each new wave of COVID-19 in different countries. There is limited data on the sustained immunity against COVID-19 in patients with liver cirrhosis. The study was aimed to compare the T cell and humoral immune response after 1 year of ChAdOx1nCoV-19 Vaccine in patients with liver cirrhosis and healthy health care workers (HCW). This was a prospective observational study including 36 HCW, 19 liver cirrhosis patients and 10 unvaccinated individuals. Anti-SARS-CoV-2S antibody, neutralizing antibody and memory T cell subsets were evaluated by ELISA and flow cytometry, respectively, in all three groups after 1 year of initial vaccination. Compared to HCW and unvaccinated individuals, liver cirrhosis patients had significantly depleted T cells, although CD4:CD8 + T cell ratio was normal. Both cirrhotic patients and HCW developed memory T cell subset [effector memory RA (P = 0.141, P < 0.001), effector memory (P < 0.001, P < 0.001), central memory (P < 0.001, P < 0.01), stem cell memory (P = 0.009, P = 0.08) and naïve (P < 0.001, P = 0.02)] compared to unvaccinated unexposed individuals of CD4 + T and CD8 + T, respectively. However, among HCW and cirrhotic group no difference was noted on central memory and stem cell memory cells on T cells. Patients with liver cirrhosis developed comparable memory T cells after vaccination which can evoke sustainable immune response on reinfection. Therefore, additional vaccine doses may not be necessary for cirrhosis patients.

Effectiveness of a fourth dose of COVID-19 mRNA vaccine in patients with systemic autoimmune rheumatic diseases using disease-modifying antirheumatic drugs: an emulated target trial

BACKGROUND

Patients with systemic autoimmune rheumatic diseases using disease-modifying antirheumatic drugs (DMARDs) might have blunted responses to COVID-19 vaccines. The initial mRNA vaccine series is defined as three doses for this population and a fourth booster dose is recommended. The effectiveness of the fourth dose in patients with systemic autoimmune rheumatic diseases using DMARDs is not well established. We aimed to assess the effectiveness of receiving versus not receiving a fourth dose of COVID-19 mRNA vaccine using a target trial framework, in a cohort of patients with systemic autoimmune rheumatic diseases receiving DMARD therapy.

METHODS

We conducted an emulated target trial using observational data from the Mass General Brigham health-care system to compare receiving versus not receiving a fourth mRNA vaccine dose. Analysed patients had systemic autoimmune rheumatic diseases, were prescribed DMARDs, and were eligible for a fourth dose of BNT162b2 or mRNA-1273 vaccines between Jan 16 and June 11, 2022. To account for temporal changes, the study period was divided into 1-week intervals. Fourth-dose-exposed patients were included in a 1-week interval if they received a fourth mRNA dose in that interval; fourth-dose-unexposed patients were eligible for but had not received the fourth dose of the vaccine. The primary outcome was a SARS-CoV-2 infection; the secondary outcome was severe SARS-CoV-2 infection (ie, admission to hospital or death within -3 to +14 days of a positive test). We assessed the effectiveness of the fourth dose using time-stratified, overlap propensity score-weighted Cox regression models.

FINDINGS

We included 4305 patients, 3126 of whom received a fourth dose of vaccine and 1179 who had not. The median follow-up time was 135 days (IQR 112-154) among patients who had received a fourth dose and 65 days (30-156) among patients who had not received a fourth dose. After overlap weighting in both groups, 1863 (72·7%) of 2563 participants were women, 700 (27·3%) were men, and 2242 (87·5%) were White. Rheumatoid arthritis was present in 1392 (54·3%) of 2563 participants; the most frequent treatments were conventional synthetic DMARDs (1489 [58·1%]) or biological DMARDs (1007 [39·3%]). SARS-CoV-2 infection risk was lower among patients receiving versus not receiving a fourth dose of vaccine (HR 0·59 [95% CI 0·47-0·74]). A fourth dose reduced the risk of admission to hospital or death within -3 to +14 days of SARS-CoV-2 infection (0·35 [0·14-0·85]).

INTERPRETATION

In this emulated target trial, a fourth dose of COVID-19 mRNA vaccine reduced the risk of SARS-CoV-2 infection and severe COVID-19 among patients with systemic autoimmune rheumatic diseases using DMARDs during the Omicron era. Patients with systemic autoimmune rheumatic diseases should be encouraged to remain up-to-date with COVID-19 vaccinations.

FUNDING

The National Institutes of Health and the National Institute of Arthritis and Musculoskeletal and Skin Diseases.

Remdesivir Reduced Mortality in Immunocompromised Patients Hospitalized for COVID-19 Across Variant Waves: Findings From Routine Clinical Practice

BACKGROUND

Immunocompromised patients are at high risk of severe coronavirus disease 2019 (COVID-19) and death, yet treatment strategies for immunocompromised patients hospitalized for COVID-19 reflect variations in clinical practice. In this comparative effectiveness study, we investigated the effect of remdesivir treatment on inpatient mortality among immunocompromised patients hospitalized for COVID-19 across all variants of concern (VOC) periods.

METHODS

Data for immunocompromised patients hospitalized for COVID-19 between December 2020 and April 2022 were extracted from the US PINC AITM Healthcare Database. Patients who received remdesivir within 2 days of hospitalization were matched 1:1 using propensity score matching to patients who did not receive remdesivir. Additional matching criteria included admission month, age group, and hospital. Cox proportional hazards models were used to examine the effect of remdesivir on risk of 14- and 28-day mortality during VOC periods.

RESULTS

A total of 19 184 remdesivir patients were matched to 11 213 non-remdesivir patients. Overall, 11.1% and 17.7% of remdesivir patients died within 14 and 28 days, respectively, compared with 15.4% and 22.4% of non-remdesivir patients. Remdesivir was associated with a reduction in mortality at 14 (hazard ratio [HR], 0.70; 95% confidence interval, .62-.78) and 28 days (HR, 0.75; 95% CI, .68-.83). The survival benefit remained significant during the pre-Delta, Delta, and Omicron periods.

CONCLUSIONS

Prompt initiation of remdesivir in immunocompromised patients hospitalized for COVID-19 is associated with significant survival benefit across all variant waves. These findings provide much-needed evidence relating to the effectiveness of a foundational treatment for hospitalized COVID-19 patients among a high-risk population.

Factors associated with uptake of bivalent mRNA COVID-19 vaccines in a large US health care system

BACKGROUND

Bivalent mRNA COVID-19 vaccines were developed to provide protection against the original SARS-CoV-2 strain and Omicron BA.4/BA.5 variants, but uptake in the United States has been low. Sociodemographic disparities in COVID-19 vaccine uptake have been documented, but it is unclear if similar disparities persist among individuals who previously completed a primary series of monovalent COVID-19 vaccine.

METHODS

We conducted a retrospective cohort study at Kaiser Permanente Southern California (KPSC) including youth aged 5-17 years and adults aged ≥18 years who were KPSC members and had completed a primary series of monovalent COVID-19 vaccine. Individuals were followed from index date (date of eligibility for bivalent vaccine) to 03/31/2023 to ascertain receipt of any dose of bivalent mRNA COVID-19 vaccine or until disenrollment from KPSC or death. Multivariable robust Poisson regression was conducted to assess the adjusted relative risk and 95 % confidence intervals of factors associated with receipt of bivalent vaccine.

RESULTS

The final cohorts included 305,339 youth and 2,534,619 adults, of whom 19.5 % and 30.7 %, respectively, had received bivalent COVID-19 vaccine. Factors associated with being more likely to receive bivalent COVID-19 vaccine included older age, Asian race, more prior year outpatient and virtual visits, Charlson score ≥1, and immunocompromised status. Factors associated with being less likely to receive a bivalent COVID-19 vaccine included age 12-17 vs 5-11 years, Hispanic and non-Hispanic Black race/ethnicity, ≥1 prior year inpatient or emergency department visits, prior history of SARS-CoV-2 infection (adults only), Medicaid insurance, and higher neighborhood deprivation index.

CONCLUSION

Even among youth and adults who had previously received a primary series of monovalent COVID-19 vaccine, sociodemographic and clinical disparities were observed in receipt of bivalent COVID-19 vaccine. These findings are critical to inform equitable strategies for the implementation of the updated monovalent COVID-19 vaccine targeting the Omicron XBB strain.

Sociodemographic disparities affect COVID-19 vaccine uptake in non-elderly adults with increased risk of severe COVID-19

BACKGROUND

There is limited information about sociodemographic disparities in COVID-19 vaccine uptake among non-elderly adults with an increased risk of severe COVID-19. We investigated the COVID-19 vaccine uptake in individuals aged 18-64 years with an increased risk of severe COVID-19 (non-elderly risk group) in Stockholm County, Sweden.

METHOD

We used population-based health and sociodemographic registries with high coverage to perform a cohort study of COVID-19 vaccine uptake of one to four doses up until 21 November 2022. The vaccine uptake in the non-elderly risk group was compared with non-risk groups aged 18-64 years (non-elderly non-risk group) and individuals aged ≥65 years (elderly).

RESULTS

The uptake of ≥3 vaccine doses was 55%, 64% and 87% in the non-elderly non-risk group (n = 1,005,182), non-elderly risk group (n = 308,904) and elderly (n = 422,604), respectively. Among non-elderly risk group conditions, Down syndrome showed the strongest positive association with receiving three doses (adjusted risk ratio [aRR] 1.62, 95% confidence interval [CI] 1.54-1.71), whereas chronic liver disease showed the strongest negative association (aRR 0.90, 95% CI 0.88-0.92). Higher vaccine uptake among the non-elderly risk group was associated with increasing age, being born in Sweden, higher education, higher income and living in a household where other adults had been vaccinated. Similar trends were observed for the first, second, third and fourth doses.

CONCLUSION

These results call for measures to tackle sociodemographic disparities in vaccination programmes during and beyond the COVID-19 pandemic.

Comparing demographics, clinical characteristics, and hospital outcomes by vaccine uptake status: A single-institution cross-sectional study

Vaccination against Coronavirus disease 2019 (COVID-19) has been the cornerstone of reducing morbidity and mortality of this disease, as it has been shown to decrease the risk of viral transmission, severity of disease, hospitalization, and intubation. However, true understanding of its impact is skewed by heterogeneous vaccine administration due to lack of equitable access, vaccine hesitancy, and varying social determinants of health. Therefore, this study aims to identify groups that are less likely to be vaccinated and understand whether the resultant differences in vaccination rates affect morbidity and mortality in socially marginalized COVID-19 patients. A retrospective cohort analysis was performed on a randomized and stratified population of 939 COVID-19 patients from January 2021 to December 2021. Bivariate analysis and logistic regression were used to assess demographic and clinical characteristic trends in unvaccinated, partially vaccinated, and fully vaccinated groups. No one age (P = .21), gender (P = .9), race (P = .12), ethnicity (P = .09), or health insurance status (P = .13) group was more vaccinated than the other. Similarly, no subgroup was at increased odds of intubation (P = .08) or death. However, patients with all categories of comorbidities including cardiopulmonary disease (P = <.001, effect size .17), renal disease (P = <.001, effect size 0.138), metabolic disease (P = .04), and immunocompromised (P = .01) states were found to have significantly higher vaccination rates. Our study also shows that full vaccination protects against mortality and decreases the odds of intubation by 55% (adjusted odds ratio = 0.453, P value = .015) compared to no vaccination or partial vaccination. Findings from this study show an encouraging trend that sicker patients had higher rates of vaccination against COVID-19. This trend highlights the need for further identification of motivators that may be applied to vaccine-hesitant populations, which can help guide population-level policy, increase vaccination campaign yield, and reach for health equity.

A Call to Action: Current Challenges and Considerations for COVID-19 Vaccination in Immunocompromised Populations

The heightened risk of infection and complexities of preventing disease in immunocompromised individuals are at the forefront of public health strategies. The COVID-19 pandemic highlighted the increased vulnerability and susceptibility to serious outcomes in this population. COVID-19 prevention efforts led to the development of vaccines, including mRNA-based options, which were initially recommended as a 2-dose primary schedule for both immunocompromised and immunocompetent individuals. However, post-rollout assessments led to updated recommendations specific to immunocompromised populations. As COVID-19 potentially transitions to become endemic disease, immunocompromised individuals will remain at high risk of severe disease; thus, the evaluation of current vaccination challenges remains crucial for guiding effective public health efforts. This article summarizes key findings from the previous articles of this supplement, highlighting current vaccination challenges for at-risk immunocompromised groups and exploring solutions to ensure protection against COVID-19 for these vulnerable populations.