Comparative Effectiveness of mRNA-based BNT162b2 Vaccine versus Adenovirus Vector-Based Ad26.COV2.S Vaccine for the Prevention of COVID-19 among Dialysis Patients.

BACKGROUND: Studies have demonstrated that mRNA-based SARS-CoV-2 vaccines are highly effective among patients on dialysis. Because individual vaccines may be differentially available or acceptable to patients, it is important to understand comparative effectiveness relative to other vaccines, such those on the basis of adenovirus technologies. METHODS: In this retrospective study, we compared the clinical effectiveness of adenovirus vector-based Ad26.COV2.S (Janssen/Johnson & Johnson) to mRNA-based BNT162b2 (Pfizer/BioNTech) in a contemporary cohort of patients on dialysis. Patients who received a first BNT162b2 dose were matched 1:1 to Ad26.COV2.S recipients on the basis of date of first vaccine receipt, US state of residence, site of dialysis care (in-center versus home), history of COVID-19, and propensity score. The primary outcome was the comparative rate of COVID-19 diagnoses starting in the 7th week postvaccination. In a subset of consented patients who received Ad26.COV2.S, blood samples were collected ≥28 days after vaccination and anti-SARS-CoV-2 immunoglobulin G antibodies were measured. RESULTS: A total of 2572 matched pairs of patients qualified for analysis. Cumulative incidence rates of COVID-19 did not differ for BNT162b2 versus Ad26.COV2.S. No differences were observed in peri-COVID-19 hospitalizations and deaths among patients receiving BNT162b2 versus Ad26.COV2.S, who were diagnosed with COVID-19 during the at-risk period. Results were similar when excluding patients with a history of COVID-19, in subgroup analyses restricted to patients who completed the two-dose BNT162b2 regimen, and in patients receiving in-center hemodialysis. SARS-CoV-2 antibodies were detected in 59.4% of 244 patients who received Ad26.COV2.S. CONCLUSIONS: In a large real-world cohort of patients on dialysis, no difference was detected in clinical effectiveness of BNT162b2 and Ad26.COV2.S over the first 6 months postvaccination, despite an inconsistent antibody response to the latter.

Real-World Effectiveness and Immunogenicity of BNT162b2 and mRNA-1273 SARS-CoV-2 Vaccines in Patients on Hemodialysis.

BACKGROUND: Patients on hemodialysis have an elevated risk for COVID-19 but were not included in efficacy trials of SARS-CoV-2 vaccines. METHODS: We conducted a retrospective, observational study to estimate the real-world effectiveness and immunogenicity of two mRNA SARS-CoV-2 vaccines in a large, representative population of adult hemodialysis patients in the United States. In separate, parallel analyses, patients who began a vaccination series with BNT162b2 or mRNA-1273 in January and February 2021 were matched with unvaccinated patients and risk for outcomes were compared for days 1-21, 22-42, and ≥43 after first dose. In a subset of consented patients, blood samples were collected approximately 28 days after the second dose and anti-SARS-CoV-2 immunoglobulin G was measured. RESULTS: A total of 12,169 patients received the BNT162b2 vaccine (matched with 44,377 unvaccinated controls); 23,037 patients received the mRNA-1273 vaccine (matched with 63,243 unvaccinated controls). Compared with controls, vaccinated patients' risk of being diagnosed with COVID-19 postvaccination became progressively lower during the study period (hazard ratio and 95% confidence interval for BNT162b2 was 0.21 [0.13, 0.35] and for mRNA-1273 was 0.27 [0.17, 0.42] for days ≥43). After a COVID-19 diagnosis, vaccinated patients were significantly less likely than unvaccinated patients to be hospitalized (for BNT162b2, 28.0% versus 43.4%; for mRNA-1273, 37.2% versus 45.6%) and significantly less likely to die (for BNT162b2, 4.0% versus 12.1%; for mRNA-1273, 5.6% versus 14.5%). Antibodies were detected in 98.1% (309/315) and 96.0% (308/321) of BNT162b2 and mRNA-1273 patients, respectively. CONCLUSIONS: In patients on hemodialysis, vaccination with BNT162b2 or mRNA-1273 was associated with a lower risk of COVID-19 diagnosis and lower risk of hospitalization or death among those diagnosed with COVID-19. SARS-CoV-2 antibodies were detected in nearly all patients after vaccination. These findings support the use of these vaccines in this population.

An open-label, single-arm study evaluating the immunogenicity and safety of the hepatitis B vaccine HepB-CpG (HEPLISAV-B®) in adults receiving hemodialysis.

BACKGROUND: Hemodialysis patients are at increased risk of hepatitis B virus (HBV) infection and are poorly responsive to HBV vaccines. Current vaccine recommendations for hemodialysis patients utilize more than twice the amount of hepatitis B surface antigen (HBsAg) used for healthy adults and achieve lower immune responses. METHODS: An open-label, single-arm, multicenter trial was conducted among adults 18 years of age and older who were initiating or undergoing hemodialysis who had not previously received hepatitis B vaccine. Participants received four doses of HepB-CpG (HEPLISAV-B®) (20 mcg rHBsAg + 3000 mcg CpG 1018, a Toll-like receptor 9 agonist) administered at 0, 4, 8, and 16 weeks. Participants are being followed for 68 weeks. This paper reports the final immunogenicity analysis of the primary endpoint at study week 20 and an interim safety analysis. RESULTS: We enrolled 119 participants receiving hemodialysis who were followed for a median of 47.4 weeks. Of the 119 participants, 75 were in the per-protocol population. At week 20, the seroprotection rate (% with antibodies to hepatitis B surface antigen [anti-HBs] ≥ 10 mIU/mL) was 89.3% and the percentage of participants with anti-HBs ≥ 100 mIU/mL was 81.3%. The anti-HBs geometric mean concentration was 1061.8 mIU/mL. HepB-CpG was well tolerated with no observed safety concerns. CONCLUSION: In patients receiving hemodialysis, HepB-CpG given as four doses was well tolerated and induced very high anti-HBs concentrations and seroprotection in a very high proportion of recipients.

A Novel Radiofrequency Device to Monitor Changes in Pulmonary Fluid in Dialysis Patients.

BACKGROUND AND OBJECTIVES: Fluid monitoring is an important management strategy in patients with chronic kidney disease (CKD) and heart failure (HF). The µCor™ Heart Failure and Arrhythmia Management System uses a radiofrequency-based thoracic fluid index (TFI) to track pulmonary edema. During hemodialysis, the acute removal of fluid through ultrafiltration offers a model for measuring a patient's fluid status. The objective of the study was to assess the relationship between the device measured TFI and ultrafiltration volume (UFV). DESIGN SETTING PARTICIPANTS AND MEASUREMENTS: Patients undergoing chronic dialysis with and without heart failure were enrolled in the study. The relationship between TFI and UFV in each individual subject was assessed by calculating the Pearson correlation coefficient (r). The average correlation across all subjects was calculated through the use of the Fisher's z transform. Responder analysis was performed to assess the magnitude of change in TFI before and after dialysis. RESULTS: Twenty subjects were enrolled in the trial. The mean volume of fluid removal was 3.63 L (SD 0.88 L). The mean correlation based on Fisher's transform was 0.95 CI (0.92-0.99). Responder analysis showed that the mean reduction of TFI after dialysis was 5.5% ± 3.8. CONCLUSION: The µCor system provides radiofrequency-based measurements of thoracic fluid which correlate well with total body fluid removal in a real-world setting. Fluid management based on the radar-derived TFI may provide benefits to dialysis patients and serves as a potential model for pulmonary edema common to the clinical course of heart failure.

Real-World Evaluation of Patiromer for the Treatment of Hyperkalemia in Hemodialysis Patients.

INTRODUCTION: Patiromer is a potassium (K+) binding polymer indicated for treating hyperkalemia. Among patients receiving chronic hemodialysis (HD), this study aimed to identify patient characteristics associated with patiromer initiation, describe patiromer utilization, and analyze serum K+ pre- and post-patiromer initiation. METHODS: In a retrospective cohort study, using electronic health record data from a large dialysis provider in the United States (study period: December 21, 2015, to December 20, 2016), HD patients were included who had a medication order for patiromer, sodium polystyrene sulfonate (SPS), or laboratory evidence of hyperkalemia (no K+ binder [NoKb] cohort). The index date was the first order for patiromer/SPS, or the first K+ ≥5.0 mEq/l (NoKb cohort), respectively. Using multivariable logistic regression, we identified patient characteristics associated with patiromer initiation. We evaluated patiromer utilization using Kaplan-Meier methodology and proportion of days covered. Serum K+ concentrations were assessed pre- versus post-patiromer initiation. RESULTS: Study cohorts included 527 (patiromer), 852 (SPS), and 8747 (NoKb) HD patients. Median follow-up was 141 days. Patiromer initiators were 2.6 times more likely to have had multiple prior episodes of hyperkalemia (odds ratio [OR]: 2.6; 95% confidence interval [CI]: 1.8-3.7). Most (61%) commenced patiromer on 8.4 g once daily; 60% of patients' first patiromer order remained open after 180 days. Statistically significant reductions in K+, averaging approximately -0.5 mEq/l, were observed post-patiromer initiation (48% pre-patiromer vs. 22% post-patiromer had K+ ≥6.0 mEq/l [P < 0.001]). CONCLUSION: Patiromer initiators receiving chronic hemodialysis had comparatively more severe, uncontrolled baseline hyperkalemia. Medication order data show long-term patiromer use was associated with significantly reduced K+.