Fourth BNT162b2 vaccination neutralization of omicron infection after heart transplantation

We investigated changes in receptor-binding domain IgG and neutralizing antibodies against the omicron and delta variants, vs the wild-type virus, in response to a fourth BNT162b2 dose in 90 heart transplant (HT) recipients. The fourth dose induced anti-RBD IgG antibodies and a higher neutralization efficiency against the wild-type virus and the variants; however, neutralization efficiency against the omicron variant was lower than that against the delta variant (the latter demonstrating efficacy similar to that against the wild-type virus). Notably, while IgG anti-RBD antibodies were detectable in >80% of the HT recipients, only about half demonstrated neutralization efficiency against the omicron variant. A SARS-CoV-2-specific-T-cell response following the fourth dose was evident in the majority of transplant recipients. Boosting vulnerable groups improves antibody responses (including neutralizing responses) and cellular immunity, but the incomplete immunological response, particularly for omicron, suggests continued preventive measures and optimization of vaccination strategies that elicit strong, and long-lasting immune responses, in this high-risk population, should remain a priority.

A third dose of the BNT162b2 mRNA vaccine significantly improves immune responses among liver transplant recipients

BACKGROUND & AIMS

Immune responses of solid organ transplant recipients to 2 doses of the BNT162b2 mRNA anti-SARS-CoV-2 vaccine are impaired. The immunogenicity and safety of a third dose among liver transplant (LT) recipients are unknown. This work aimed to evaluate the immune response of LT recipients to a third dose of the BNT162b2 mRNA vaccine.

METHODS

Consecutive LT recipients (n = 61) in follow-up at Sheba Medical Center were included. Receptor binding domain (RBD) IgG, neutralizing antibody (NA) titers, and T-cell levels before and 21-28 days after a third vaccine dose were determined. Adverse effects after the third dose were monitored.

RESULTS

The median age of LT recipients was 65 years and 57.4% were male. The humoral immune response rate improved significantly, with 56% of patients showing a response before the third vaccine dose compared to 98% after the third dose. The cellular response in 12 evaluated patients improved significantly (p = 0.008). The geometric mean of anti-RBD IgG levels, NA levels, and T-cell count also increased significantly after the third dose. NA titers after the third dose negatively correlated with age (p = 0.03), mycophenolate mofetil treatment (p = 0.005), and combined immunosuppression as opposed to calcineurin inhibitor monotherapy (p = 0.001). After the third dose, adverse effects were reported by 37% of recipients and were mostly mild (local pain and fatigue).

CONCLUSION

After a third BNT162b2 mRNA vaccine, the immune response improved significantly among LT recipients, without serious adverse effects. Further studies are needed to evaluate immune response durability and to determine the optimal number and schedule of booster vaccine doses.

LAY SUMMARY

The Pfizer-Biotech BNT162b2SARS-CoV-2 vaccine induced significant immunity among liver transplant recipients after a third dose. The majority of the patients developed sufficient levels of both humoral and cellular immune responses. Factors that predict non-response were older age and immunosuppressive medications.

Hospitalized Patients With Severe Coronavirus Disease 2019 During the Omicron Wave in Israel: Benefits of a Fourth Vaccine Dose

BACKGROUND

Waning immunity and an increased incidence of coronavirus disease 2019 (COVID-19) during the Omicron outbreak led the Israeli Ministry of Health to recommend a fourth vaccine dose for high-risk individuals. In this study, we assessed its effect for hospitalized patients with severe breakthrough COVID-19.

METHODS

In this multicenter cohort study of hospitalized adults with severe COVID-19 in Israel, from 15 to 31 January 2022, cases were divided according to the number of vaccinations received. Poor outcome was defined as mechanical ventilation or in-hospital death and was compared between 3- and 4-dose vaccinees using logistic regression.

RESULTS

Included were 1049 patients, median age 80 years. Among them, 394 were unvaccinated, 386 and 88 had received 3 or 4 doses, respectively. The 3-dose group was older, included more males, and immunosuppressed patients but with similar outcomes, 49% vs 51% compared with unvaccinated patients (P = .72). Patients who received 4 doses were similarly older and immunosuppressed but had better outcomes compared with unvaccinated patients, 34% vs 51% (P < .01). We examined independent predictors for poor outcome in patients who received either 3 or 4 doses a median of 161 days or 14 days before diagnosis, respectively. Receipt of the fourth dose was associated with protection (odds ratio, 0.51; 95% confidence interval, .3-.87), as was remdesivir. Male sex, chronic renal failure, and dementia were associated with poor outcomes.

CONCLUSIONS

Among hospitalized patients with severe breakthrough COVID-19, a recent fourth dose was associated with significant protection against mechanical ventilation or death compared with 3 doses.

Evaluation of the clinical impact of bone marrow cultures in current medical practice

The clinical yield and benefit of performing bone marrow cultures for various clinical indications has been challenged and their clinical necessity remains debatable. We sought to assess the clinical yield and benefit of performing routine bone marrow cultures and determine whether various clinical, laboratory, and imaging parameters were predictive of a diagnostic bone marrow culture. This was a single center retrospective analysis of all patients who underwent a bone marrow study comprising bone marrow cultures from January 1, 2012, through March 1, 2018. Baseline clinical data were extracted from the institution's electronic medical records system. The analyzed cohort consisted of 139 patients with a median age of 46 years (range 4 months to 85 years). The most common indication for a bone marrow study was workup of a fever of unknown origin (105 patients, 76%) while investigation for infection in immunocompromised patients accounted for 22 cases (16%) and suspected tuberculosis was the reason for acquisition of bone marrow cultures in 6 patients (4%). Only 3 patients had positive bone marrow cultures, yielding in 2 patients a diagnosis of Mycobacterium avium and in one patient a microbiologically unclassifiable fungal infection. A univariate analysis revealed that mean age, hemoglobin level, platelet count, c-reactive protein levels, gender, indication for bone marrow study, yield of blood cultures, and contribution of imaging studies and bone marrow pathology results were not significantly different between patients with diagnostic and non-diagnostic bone marrow cultures. Mean white blood cell count was found to be significantly lower in patients with diagnostic bone marrow cultures (2.4 × 10³/µL versus 8.7 × 10³/µL; P = 0.038). We conclude that for most patients, performance of bone marrow cultures holds limited clinical value.

Serological response to a third booster dose of BNT162b2 COVID-19 vaccine among seronegative cancer patients

Background and Aim

The BNT162b2 COVID‐19 vaccine (Pfizer/BioNTech), given as a two‐dose series, 3 weeks apart, elicits a serological response in 84–98% of patients with cancer, even if administered while undergoing anticancer treatments. Herein, we report the impact of a third (booster) dose of BNT162b2, delivered 6 months following the second vaccine dose.

Methods

This pilot study included four patients with cancer who were seronegative after two vaccine doses, and received a third (booster) dose of BNT162b2 at 6 months following the second vaccine dose. The four patients received the three vaccine doses between December 2020 and July 2021. Samples were evaluated with an enzyme‐linked immunosorbent assay (ELISA) that detects IgG (Immunoglobulin G) antibodies against the RBD (receptor‐binding domain) of SARS‐CoV‐2.

Results

At a mean time of 19 days (ranges 7–28) after the second vaccination, all four patients were seronegative for RBD‐IgG. However, at a mean time of 21 days (ranges 20–22) after the third dose, three out of the four patients (75%) were now seropositive. Mean RBD‐IgG titers were increased after the third vaccine dose from 0.37 to 2.81 (Student's t‐test, p = 0.05, two‐sided).

Conclusions

Although limited by the small sample size, our findings suggest that a third (booster) dose administered to patients with cancer, who remain seronegative despite two doses of BNT162b2, may be efficacious in eliciting an antibody response.

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.

The emergence of a multidrug resistant Salmonella Muenchen in Israel is associated with horizontal acquisition of the epidemic pESI plasmid

OBJECTIVES

Horizontal acquisition of mobile genetic elements is a powerful evolutionary driving force that can profoundly affect pathogens epidemiology and their interactions with the environment and host. In the last decade, the role of the epidemic megaplasmid, pESI was demonstrated in the global emergence of multi-drug resistant (MDR) Salmonella enterica serovar Infantis strains, but it was unknown if this was a one-time phenomenon, or that pESI can drive the emergence of other pathogens.

METHODS

Epidemiological, molecular, whole genome sequencing, de-novo assembly, bioinformatics and genetic approaches were used to analyze the emergence of a pESI-positive Salmonella enterica serovar Muenchen strain in Israel.

RESULTS

Since 2018, we report the emergence and high prevalence of S. Muenchen in Israel, which consisted at 2020, 40% (1055/2671) of all clinical Salmonella isolates. We show that the emergence of S. Muenchen is dominated by a clonal MDR strain, report its complete assembled genome sequence, and demonstrate that in contrast to preemergent strains, it harbors the epidemic megaplasmid, pESI, which can be self-mobilized into E. coli and other Salmonella serovars. Additionally, we identified bioinformatically highly similar genomes of clinical isolates that were recently collected in South Africa, UK and USA.

CONCLUSIONS

This is a second documented case of a pathogen emergence associated with pESI acquisition. Considering the genetic cargo of pESI that enhances resistance, stress tolerance and virulence, and its ability to conjugate into prevalent Salmonella serovars, we provide further support that pESI facilities the emergence and spreading of new Salmonella strains.

Hospitalised patients with breakthrough COVID-19 following vaccination during two distinct waves in Israel, January to August 2021: a multicentre comparative cohort study

BackgroundChanging patterns of vaccine breakthrough can clarify vaccine effectiveness.AimTo compare breakthrough infections during a SARS-CoV-2 Delta wave vs unvaccinated inpatients, and an earlier Alpha wave.MethodsIn an observational multicentre cohort study in Israel, hospitalised COVID-19 patients were divided into three cohorts: breakthrough infections in Comirnaty-vaccinated patients (VD; Jun-Aug 2021) and unvaccinated cases during the Delta wave (ND) and breakthrough infections during an earlier Alpha wave (VA; Jan-Apr 2021). Primary outcome was death or ventilation.ResultsWe included 343 VD, 162 ND and 172 VA patients. VD were more likely older (OR: 1.06; 95% CI: 1.05-1.08), men (OR: 1.6; 95% CI: 1.0-2.5) and immunosuppressed (OR: 2.5; 95% CI: 1.1-5.5) vs ND. Median time between second vaccine dose and admission was 179 days (IQR: 166-187) in VD vs 41 days (IQR: 28-57.5) in VA. VD patients were less likely to be men (OR: 0.6; 95% CI: 0.4-0.9), immunosuppressed (OR: 0.3; 95% CI: 0.2-0.5) or have congestive heart failure (OR: 0.6; 95% CI: 0.3-0.9) vs VA. The outcome was similar between all cohorts and affected by age and immunosuppression and not by vaccination, variant or time from vaccination.ConclusionsVaccination was protective during the Delta variant wave, as suggested by older age and greater immunosuppression in vaccinated breakthrough vs unvaccinated inpatients. Nevertheless, compared with an earlier post-vaccination period, breakthrough infections 6 months post-vaccination occurred in healthier patients. Thus, waning immunity increased vulnerability during the Delta wave, which suggests boosters as a countermeasure.

A Practical Clinical Score Predicting Respiratory Failure in COVID-19 Patients

BACKGROUND

The coronavirus disease 2019 (COVID-19) pandemic resulted in repeated surges of patients, sometimes challenging triage protocols and appropriate control of patient flow. Available models, such as the National Early Warning Score (NEWS), have shown significant limitations. Still, they are used by some centers to triage COVID-19 patients due to the lack of better tools.

OBJECTIVES

To establish a practical and automated triage tool based on readily available clinical data to rapidly determine a distinction between patients who are prone to respiratory failure.

METHODS

The electronic medical records of COVID-19 patients admitted to the Sheba Medical Center March-April 2020 were analyzed. Population data extraction and exploration were conducted using a MDClone (Israel) big data platform. Patients were divided into three groups: non-intubated, intubated within 24 hours, and intubated after 24 hours. The NEWS and our model where applied to all three groups and a best fit prediction model for the prediction of respiratory failure was established.

RESULTS

The cohort included 385 patients, 42 of whom were eventually intubated, 15 within 24 hours or less. The NEWS score was significantly lower for the non-intubated patients compared to the two other groups. Our improved model, which included NEWS elements combined with other clinical data elements, showed significantly better performance. The model's receiver operating characteristic curve had area under curve (AUC) of 0.92 with of sensitivity 0.81, specificity 0.89, and negative predictive value (NPV) 98.4% compared to AUC of 0.63 with NEWS. As patients deteriorate and require further support with supplemental O2, the need for re-triage emerges. Our model was able to identify those patients on supplementary O2 prone to respiratory failure with an AUC of 0.86 sensitivity 0.95, and specificity 0.7 NPV 98.9%, whereas NEWS had an AUC of 0.76. For both groups positive predictive value was approximately 35.

CONCLUSIONS

Our model, based on readily available and simple clinical parameters, showed an excellent ability to predict negative outcome among patients with COVID-19 and therefore might be used as an initial screening tool for patient triage in emergency departments and other COVID-19 specific areas of the hospital.

BNT162b2 Third Booster Dose Significantly Increases the Humoral Response Assessed by Both RBD IgG and Neutralizing Antibodies in Renal Transplant Recipients

Background: An impaired humoral response to full dose of BNT162b2 vaccine was observed in renal transplant recipients (RTR).

Methods: To reveal predictors for humoral response to third vaccine, patients were stratified to positive (N = 85) and negative (N = 14) response groups based on receptor-binding domain (RBD) IgG ≥1.1 and neutralizing antibodies (NA) ≥ 16 dilution versus RBD IgG <1.1 or NA < 16, respectively. NA were detected using a SARS-CoV-2 pseudo-virus.

Results: Response rate increased from 32.3% (32/99) before the third dose to 85.9% (85/99) post-third vaccine with a significant rise in geometric mean titers (GMTs) for RBD IgG and NA [0.79 (95% CI 0.65–0.96) vs. 3.08 (95% CI 2.76–3.45), p < 0.001 and 17.46 (95% CI 12.38–24.62) vs. 362.2 (95% CI 220.7–594.6), p < 0.001 respective. 80.6% (54/67) seroconverted and 96.9% (31/32) remained positive following the vaccine with a significant increase in GMTs for RBD IgG and NA. Age, ESRD secondary to diabetic nephropathy (DN) and renal allograft function were independent predictors for antibody response in RTR. Mycophenolic acid (MPA) use and dose had no impact on humoral response following the third booster. AEs were recorded for 70.1% of RTR population. Systemic AEs were more common in recipients with a positive humoral response as opposed to non-responders (45.2% versus 15.4% respectively, p = 0.04).

Conclusion: 85.9% of RTR develop NA to BNT162b2 third vaccine, found effective in both negative and positive responders prior to the vaccine. Antigenic re-exposure overcame the suppressive effect of MPA on antibody response in RTR.

The ancestral stringent response potentiator, DksA has been adapted throughout Salmonella evolution to orchestrate the expression of metabolic, motility, and virulence pathways

DksA is a conserved RNA polymerase-binding protein known to play a key role in the stringent response of proteobacteria species, including many gastrointestinal pathogens. Here, we used RNA-sequencing of Escherichia coli, Salmonella bongori and Salmonella enterica serovar Typhimurium, together with phenotypic comparison to study changes in the DksA regulon, during Salmonella evolution. Comparative RNA-sequencing showed that under non-starved conditions, DksA controls the expression of 25%, 15%, and 20% of the E. coli, S. bongori, and S. enterica genes, respectively, indicating that DksA is a pleiotropic regulator, expanding its role beyond the canonical stringent response. We demonstrate that DksA is required for the growth of these three enteric bacteria species in minimal medium and controls the expression of the TCA cycle, glycolysis, pyrimidine biosynthesis, and quorum sensing. Interestingly, at multiple steps during Salmonella evolution, the type I fimbriae and various virulence genes encoded within SPIs 1, 2, 4, 5, and 11 have been transcriptionally integrated under the ancestral DksA regulon. Consequently, we show that DksA is necessary for host cells invasion by S. Typhimurium and S. bongori and for intracellular survival of S. Typhimurium in bone marrow-derived macrophages (BMDM). Moreover, we demonstrate regulatory inversion of the conserved motility-chemotaxis regulon by DksA, which acts as a negative regulator in E. coli, but activates this pathway in S. bongori and S. enterica. Overall, this study demonstrates the regulatory assimilation of multiple horizontally acquired virulence genes under the DksA regulon and provides new insights into the evolution of virulence genes regulation in Salmonella spp.

Immunogenicity and Adverse Effects of the 2-Dose BNT162b2 Messenger RNA Vaccine Among Liver Transplantation Recipients

The BNT162b2 messenger RNA (mRNA) vaccine against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been shown to be safe and effective in immunocompetent patients. The safety and efficacy of this vaccine in liver transplantation (LT) recipients is still under evaluation. The objective of this study was to assess the safety and efficacy of the BNT162b2 vaccine among transplant recipients. The immune responses of 76 LT recipients receiving 2 doses of the vaccine were compared with those of 174 age-matched immunocompetent controls. Postvaccination immunoglobulin G (IgG) antibodies against the receptor-binding domain (RBD) of SARS-CoV-2 and neutralizing antibodies (NA) to the BNT162b2 mRNA vaccine were determined at least 14 days after the second dose of the vaccine. IgG antibody titers ≥1.1 were defined as positive antibodies. Adverse effects were monitored during the study period. Following administration of the second dose, transplant recipients showed reduced immune responses compared with controls (72% versus 94.2%; P < 0.001). At a median time of 38 days after the second vaccination, the geometric mean of RBD IgG and NA titers were 2.1 (95% confidence interval [CI], 1.6-2.6) and 150 (95% CI, 96-234) among transplant recipients and 4.6 (95% CI, 4.1-5.1) and 429 (95% CI, 350-528) in the control group, respectively (P < 0.001). Antibody responses were lower in transplant recipients who were receiving combined immunosuppression therapy and in those with impaired renal function. Among the LT recipients with negative antibody responses, 1 became infected with SARS-CoV-2, but no recipients with positive antibody responses became infected. Overall, most (n = 39 [51%]) adverse effects self-reported by transplant recipients were mild and occurred more often in women than in men. Compared with patients who were immunocompetent, LT recipients had lower immune responses. The durability of immune responses to the BNT162b2 vaccine among LT recipients requires further investigation.

Third dose of the BNT162b2 vaccine in heart transplant recipients: Immunogenicity and clinical experience

BACKGROUND

The repeated waves of the COVID-19 pandemic have highlighted the necessity to optimize vaccine responses in immunocompromised populations. We investigated the safety and immunogenicity of a third, booster, dose of the Pfizer BNT162b2 vaccine in heart transplant (HT) patients.

METHODS

The cohort comprised 96 adult HT patients who received a third homologous dose of the BNT162b2 vaccine 168 days after the second dose. The vaccine-induced antibody responses of both receptor-binding domain (RBD) IgG and neutralizing antibodies were assessed in all patients, with a positive antibody response being defined as the presence of either IgG anti-RBD or neutralizing antibodies. For a subset of patients, T cell response was also studied.

RESULTS

The third dose was associated with a low rate of adverse events, mostly mild pain at the injection site. No serious adverse events were recorded, and there were no episodes of rejection. At 18 days following the third dose of the vaccine, the positive antibody response increased from 23% to 67%, with a corresponding increase in neutralizing capacity. The third dose elicited SARS-CoV-2 neutralization titers >9-fold and IgG anti-RBD antibodies >3-fold of the range achieved after the two primary doses. Mycophenolate use, lower eGFR and higher C-reactive protein were independently associated with a reduced likelihood of generating an immune response. Importantly, a specific T-cell response following the third dose was evident in the majority of transplant recipients.

CONCLUSIONS

An homologous third booster dose of the BNT162b2 vaccine gave overall consistent tolerability and a good safety profile, while eliciting humoral and cellular immune responses.

Early Immunogenicity and safety of the third dose of BNT162b2 mRNA Covid-19 vaccine among adults older than 60 years; real world experience

BACKGROUND

Despite high vaccine coverage, an increase in breakthrough COVID-19 infections, prompted administration of a third BNT162b2 dose to people>60 years in Israel since July 2021. Here, we report real-world immunogenicity following third dose.

METHODS

Overall, 208 healthcare workers aged>60 were included. Paired pre- and post-second and/or -third dose IgG and neutralizing-antibody titers were compared. A subpopulation of low-responders to the second dose were also tested for T-cell activation. For 25 paired serum samples we tested neutralization of wild-type vs. neutralization of delta and lambda variants, pre- and post-third dose. Active surveillance of vaccine adverse-events was conducted through surveys.

RESULTS

A pronounced immune response was observed following the third dose, including a 33-fold and 51-fold increase in IgG and neutralizing ab, respectively. The neutralizing antibody levels post-third-dose were 9.34 times higher than post-second-dose (GMT 2598 95%CI 2085-3237 vs. 207 95%CI 126-339). Nine previously low-responders, had a significant antibody increase post-third-dose, and 7/9 showed increase in T cell activation. Additionally, sera obtained post-third-dose, highly and comparably neutralized the wild-type, delta and lambda variants. Of 1056 responders to the adverse-event survey, none had serious events.

CONCLUSIONS

We demonstrate a rapid and broad immune response to the third BNT162b2 dose in individuals>60 years.

BNT162b2 vaccine breakthrough: clinical characteristics of 152 fully vaccinated hospitalized COVID-19 patients in Israel

OBJECTIVES

The mRNA coronavirus disease 2019 (COVID-19) vaccines have shown high effectiveness in the prevention of symptomatic COVID-19, hospitalization, severe disease and death. Nevertheless, a minority of vaccinated individuals might become infected and experience significant morbidity. Characteristics of vaccine breakthrough infections have not been studied. We sought to portray the population of Israeli patients, who were hospitalized with COVID-19 despite full vaccination.

METHODS

A retrospective multicentre cohort study of 17 hospitals included patients fully vaccinated with Pfizer/BioNTech's BNT162b2 vaccine who developed COVID-19 more than 7 days after the second vaccine dose and required hospitalization. The risk for poor outcome, defined as a composite of mechanical ventilation or death, was assessed.

RESULTS

A total of 152 patients were included, accounting for half of hospitalized fully vaccinated patients in Israel. Poor outcome was noted in 38 patients and mortality rate reached 22% (34/152). Notably, the cohort was characterized by a high rate of co-morbidities predisposing to severe COVID-19, including hypertension (108; 71%), diabetes (73; 48%), congestive heart failure (41; 27%), chronic kidney and lung diseases (37; 24% each), dementia (29; 19%) and cancer (36; 24%), and only six (4%) had no co-morbidities. Sixty (40%) of the patients were immunocompromised. Higher viral load was associated with a significant risk for poor outcome. Risk also appeared higher in patients receiving anti-CD20 treatment and in patients with low titres of anti-Spike IgG, but these differences did not reach statistical significance.

CONCLUSIONS

We found that severe COVID-19 infection, associated with a high mortality rate, might develop in a minority of fully vaccinated individuals with multiple co-morbidities. Our patients had a higher rate of co-morbidities and immunosuppression compared with previously reported non-vaccinated hospitalized individuals with COVID-19. Further characterization of this vulnerable population may help to develop guidance to augment their protection, either by continued social distancing, or by additional active or passive vaccinations.

Humoral Response of Renal Transplant Recipients to the BNT162b2 SARS-CoV-2 mRNA Vaccine Using Both RBD IgG and Neutralizing Antibodies

BACKGROUND

Data about SARS-CoV-2 vaccines efficacy in renal transplant recipients (RTR) are lacking.

METHODS

To reveal predictors for humoral response to BNT162b2 vaccine among RTR, patients were divided into positive (N = 42) and negative (N = 78) response groups based on receptor-binding domain (RBD) immunoglobulin G (IgG) ≥1.1 and neutralizing antibodies (NA) ≥16 dilution versus RBD IgG <1.1 or NA <16, respectively. NA were detected using a SARS-CoV-2 pseudo-virus.

RESULTS

NA were detected in only 42 of 120 (35%) of RTR versus 197 of 202 (97.5%) immunocompetent controls (P < 0.001). NA geometric mean titers in RTR were significantly lower versus the control group {83.7 (95% confidence interval [CI], 50.5-138.8) versus 482 (95% CI, 411-566), P < 0.001}. In a multivariable analysis, mycophenolic acid (MPA) dose and hemoglobin level were found to be independent predictors for antibody response in RTR. A positive response rate of 27% versus 63% was observed in patients on and off MPA, respectively. An increase in MPA dose by 1 mg/kg weight reduced the odds for a positive response by 17% (odds ratio = 0.83; 95% CI, 0.75-0.92; P < 0.001). Geometric mean titers for RBD IgG were significantly reduced as MPA daily dose increased. Hemoglobin blood level <13 g/dL reduced the antibody response by 63% (P = 0.04). Pain at the injection site after the second vaccine dose was significantly higher in the responders versus nonresponders (20.5% versus 5.5%, P = 0.01).

CONCLUSIONS

Only 35% of RTR develop NA to the BNT162b2 mRNA vaccine. MPA is a major suppressor of antibody response in RTR.

BNT162b2 mRNA COVID-19 vaccination in immunocompromised patients: A prospective cohort study

BACKGROUND

Trials of the Pfizer-BioNTech BNT162b2 mRNA vaccine showed 95% efficacy in preventing symptomatic disease; however, the trials excluded immunocompromised patients (ICPs). We aim at analyzing antibody response in ICPs.

METHODS

A prospective cohort study was conducted at Sheba Medical Center, Israel, between January and April 2020, in 1274 participants who received the vaccine, including 1002 ICPs and 272 immunocompetent healthcare workers (HCWs). Antibodies were measured two-four weeks after vaccination by SARS-CoV-2 anti-receptor binding domain IgG antibodies (RBD IgG) and pseudo-virus neutralization assays. Multivariable logistic regression analyses were used to identify factors associated with vaccine-induced antibody response. Adverse events (AEs) were monitored.

FINDINGS

RBD-IgG antibodies were detected in 154/156 (98.7%) of patients with HIV, 75/90 (83.3%) with solid malignancies, 149/187 (79.7%) with myeloma, 83/111 (74.8%) following hematopoietic stem cell transplants, 25/36 (69.4%) following liver transplantation, 26/43 (60.5%) with myelodysplastic syndrome, 96/188 (51.0%) with chronic lymphocytic leukemia/non-Hodgkin's lymphoma, 50/110 (45.5%) following kidney transplantation, 15/80 (18.8%) following heart transplantation, and 269/272 (98.9%) in controls. There was a significant correlation r = 0.74 (95%CI 0.69,0.78) between RBD-binding IgG and neutralizing antibodies in all groups. Multivariate logistic regression analysis showed that age > 65 years (OR 0.41,95%CI 0.30,0.57) and underlying immunosuppression (OR 0.02,95%CI 0.01,0.07) were significantly associated with a non-reactive response of IgG antibodies. HIV patients showed a similar immunological response as healthy adults. The vaccine was safe without any episodes of rejection, graft-versus-host disease (GVHD) or allergy. Immunocompetent HCWs experienced significantly more AEs than ICPs.

INTERPRETATION

Antibody response to the Pfizer-BioNTech vaccine was highly variable among different ICPs; thus, individual recommendations should be provided for the different immunosuppression states.

Immunogenicity and safety of the BNT162b2 mRNA COVID-19 vaccine in haematopoietic stem cell transplantation recipients

The immunogenicity and safety of Pfizer‐BioNTech BNT162b2 mRNA vaccine in allogeneic haematopoietic stem cell transplantation (HSCT) recipients are unknown. We prospectively followed 152 HSCT recipients who were at least six months following transplantation and with no active acute graft‐versus‐host disease (GVHD). Blood samples were taken 2–4 weeks after the second vaccination and analyzed for receptor‐binding domain (RBD) antibodies and neutralizing antibodies (NA). 272 immunocompetent healthcare workers served as controls. At a median of 28 days after the second vaccination, 118 patients (77·6%) developed RBD immunoglobulin G (IgG) with a geometric mean titre (GMT) of 2·61 [95% CI (confidence interval), 2·16–3·16]. In the control group 269/272 (98·9%) developed RBD IgG, with a GMT of 5·98 (95% CI 5·70–6·28), P < 0·0001. The GMT of NA in HSCT recipients and controls was 116·0 (95% CI 76·5–175·9), and 427·9 (95% CI 354·3–516·7) respectively (P < 0001). Multivariate logistic regression analysis revealed that HSCT recipients with no chronic GVHD and no immunosuppressive therapy at the time of vaccination had significantly higher levels of NA following the second vaccination. Adverse events were minimal and were less common than in healthy controls. In conclusion; the BNT162b2 mRNA vaccination is safe and effective in HSCT recipients, especially those who are immunosuppression‐free. A significant fraction developed protecting NA.

Automated processing of thermal imaging to detect COVID-19 and microvascular dysfunction

Background

Coronavirus disease 2019 (COVID-19) is associated with microvascular dysfunction. Non-invasive thermal imaging can hypothetically detect changes in perfusion, inflammation and vascular injury. We sought to develop a new point-of-care, non-contact thermal imaging tool to detect COVID-19 by microvascular dysfunction, based on image processing algorithms and machine learning analysis.

Materials and methods

We captured thermal images of the back of 101 individuals, with (n=62) and without (n=39) COVID-19, using a portable thermal camera that connects directly to smartphones. We developed new image processing algorithms that automatically extract multiple texture and shape features of the thermal images (Figure 1A). We then evaluated the ability of our thermal features to detect COVID-19 and systemic changes of heat distribution associated with microvascular disease. We also assessed correlations between thermal imaging to conventional biomarkers and chest X-ray (CXR).

Results

Our novel image processing algorithms achieved up to 92% sensitivity in detecting COVID-19 with an area under the curve of 0.85 (95% CI: 0.78, 0.93; p&lt;0.01). Systemic alterations in blood flow associated with vascular disease were observed across the entire back. Thermal imaging scores were inversely correlated with clinical variables associated with COVID-19 disease progression, including blood oxygen saturation, C- reactive protein, and D-dimer. The thermal imaging findings were not correlated with the results of CXR.

Conclusions

We show, for the first time, that a hand-held thermal imaging device can be used to detect COVID-19. Non-invasive thermal imaging could be used to screen for COVID-19 in out-of-hospital settings, especially in low-income regions with limited imaging resources. Moreover, thermal imaging might detect micro-angiopathies and endothelial dysfunction in patients with COVID-19 and could possibly improve risk stratification of infected individuals (Figure 1B).

Funding Acknowledgement

Type of funding sources: Public Institution(s). Main funding source(s): 1. The Israel Innovation Authority2. The Nicholas and Elizabeth Slezak Super Center for Cardiac Research and Biomedical Engineering at Tel Aviv University Figure 1. A. Representative steps of our thermal image processing algorithms. B. A schematic illustration of the research design and potential impact.

Efficacy and safety of BNT162b2 vaccination in patients with solid cancer receiving anticancer therapy - a single centre prospective study

AIM

Patients with cancer are at an increased risk for severe coronavirus disease of 2019, thus data on the safety and efficacy of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) vaccines are essential. We conducted this prospective study of patients with cancer vaccinated with BNT162b2 and monitored for antibody response and safety. The aim was to evaluate the rate of seropositivity and define predictors for non-reactive immune response. Furthermore, we evaluated the frequency and the severity of adverse events.

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) immunoglobulin G (IgG) and neutralising antibodies were measured 2-4 weeks after each vaccine dose.

RESULTS

The analysis included 129 patients, of which 70.5% patients were metastatic. Patients were treated with chemotherapy (55%), immunotherapy (34.1%), biological agents (24.8%), hormonal treatment (8.5%) and radiotherapy (4.6%), that were given either alone or in combinations. The seropositivity rate among patients with cancer and controls was 32.4% versus 59.8% (p < 0.0001) after the first dose and 84.1% versus 98.9% (p < 0.0001) after the second dose, respectively. Median RBD-IgG titre was lower among patients than controls (p < 0.0001). Patients who were seronegative after the second dose had significantly more comorbidities than that with patients with seropositivity (77.8% vs 41.1%, respectively, p = 0.0042).

CONCLUSION

Adequate antibody response after BNT162b2 vaccination was achieved after two doses but not after one dose, in patients with cancer vaccinated during anticancer therapy.