Poor neutralizing antibody responses in 106 patients with WM after vaccination against SARS-CoV-2: a prospective study

The impact of Bruton's tyrosine kinase inhibitor treatment on COVID-19 outcomes in Chinese patients with chronic lymphocytic leukemia

Background

Impact of B-cell depletion following treatment with Bruton tyrosine kinase-inhibitors (BTKi) on the outcome of SARS-CoV-2 infection in chronic lymphocytic leukemia (CLL) patients remain controversial. We investigated the impact of BTKi on susceptibility and the severity of COVID-19 in Chinese patients with CLL during the first wave of COVID-19 (Omicron variant).

Methods

CLL patients (n=171) visiting the Institute of Hematology, Peoples' Hospital, China (November 15, 2022- January 20, 2023) were included in the study. Seventeen patients receiving BTKi and venetoclax with or without obinutuzumab were excluded. Data from 117 patients receiving treatment with BTKi were collected using a standardized questionnaire through telephone interviews. Thirty-four patients without CLL-specific treatment served as controls. The data was analysed using IBM SPSS Software version 21 and a P value of <0.05 was considered statistically significant.

Results

The median age of patients was 67 years and majority were males (n=100). Treatment with BTKi was not associated with higher incidence of COVID-19 (74% [95% Confidence Interval (CI) 60%, 92%]) versus 74% (CI 48%, 100%) without any treatment (P=0.92). Hypoxemia was reported by 45% (32%, 61%) and 16% (4%, 41%) (P=0.01). BTKi was the only independent risk factor of hypoxemia (Hazard Ratio [HR], 4.22 [1.32, 13.50]; P = 0.02). Five (5.7%) patients with COVID-19 under BTKi required ICU admission; 4 of them died. No ICU admissions/deaths were observed in the control group.

Conclusion

In Chinese patients with CLL and treated with BTKi experienced more severe lung disease and ICU admissions due to COVID-19 than patients without CLL therapy. Frequency of infections with SARS-CoV-2, however, was not different in patients with or without BTKi treatment.

Immunogenicity and safety of vaccines in multiple sclerosis: A systematic review and meta-analysis

BACKGROUND

Seroconversion rate of vaccines varies and requires further elucidation in patients with multiple sclerosis (MS) under treatment with disease-modifying therapies (DMTs). We aimed to investigate this in a systematic review and meta-analysis.

METHODS

MEDLINE(PubMed) and Cochrane databases were searched based on a pre-specified protocol (PROSPERO: CRD42020202018). Studies reporting on patients with MS, diagnosed with McDonald criteria getting vaccinated with any type of vaccine were included in the analysis. The primary endpoint was the incidence of patients being seropositive and experience adverse events after vaccination. Outcomes were expressed as proportions with respective 95% confidence interval (CI). Two reviewers independently screened and reviewed existing literature and assessed study quality with the Methodological index for non-randomized studies.

RESULTS

Of 295 articles, 45 studies were analyzed. Seroconversion after COVID-19 vaccines was 76% (95% CI, 70-80; I2 = 95%; 20 studies including 5601 patients. Protection was lower in patients treated with anti-CD20 antibodies and sphingosine-1-phosphate receptor (S1PR) modulators compared to untreated patients or treatment with other DMTs. Relapse occurred in 2% (95% CI, 1-3; I2 = 86%; 16 studies including 7235 patients). Seroconversion after seasonal influenza vaccines was 82% (95% CI, 65-91; I2 = 90%; 6 studies including 490 patients). Relapse rate was similar to this after COVID-19 vaccination.

CONCLUSION

The majority of MS patients vaccinated for COVID-19 or seasonal influenza mount an adequate immune response without safety concerns. Data on other vaccines are limited.

Pierre F, Karmali R, Mi X, Boyer J, Nieves M, Ison MG, Winter JN, Gordon LI, Ma S. Humoral Immunity After COVID-19 Vaccination in Chronic Lymphocytic Leukemia and Other Indolent Lymphomas: A Single-Center Observational Study

BACKGROUND

Chronic lymphocytic leukemia (CLL) and other non-Hodgkin's lymphomas (NHLs) lead to broad immunosuppression, conferring a greater risk for morbidity and mortality from SARS-CoV-2. Our study analyzed antibody (Ab) seropositivity from SARS-CoV-2 vaccination in patients with these cancers.

METHODS

In the final analysis, 240 patients were involved, and seropositivity was defined as a positive total or spike protein Ab.

RESULTS

Seropositivity was 50% in CLL, 68% in WM, and 70% in the remaining NHLs. Moderna vaccination led to higher seropositivity compared to Pfizer vaccination across all cancers (64% vs. 49%; P = .022) and specifically CLL patients (59% vs. 43%; P = .029). This difference was not explainable by differences in treatment status or prior anti-CD20 monoclonal Ab therapy. In CLL patients, current or prior cancer therapy led to lower seropositivity compared to treatment-naïve patients (36% vs. 68%; P = .000019). CLL patients treated with Bruton's tyrosine kinase (BTK) inhibitors had better seropositivity after receiving the Moderna vaccination compared to Pfizer (50% vs. 23%; P = .015). Across all cancers, anti-CD20 agents within 1 year led to a lower Ab response compared to greater than one year (13% vs. 40%; P = .022), a difference which persisted after booster vaccination.

CONCLUSION

Antibody response is lower in patients with indolent lymphomas compared to the general population. Lower Ab seropositivity was found in patients with a history of anti-leukemic agent therapy or those immunized with Pfizer vaccine. This data suggests that Moderna vaccination may confer a greater degree of immunity against SARS-CoV-2 in patients with indolent lymphomas.

Immune response to COVID-19 vaccination in patients with Waldenström macroglobulinaemia who pause their BTKi therapy

Patients with Waldenström macroglobulinaemia (WM) are at increased risk of severe COVID-19 infection and have poor immune responses to COVID-19 vaccination. This study assessed whether a closely monitored pause in Bruton's Tyrosine Kinase inhibitor (BTKi) therapy might result in an improved humoral response to a 3rd COVID-19 vaccine dose. Improved response was observed in WM patients who paused their BTKi, compared to a group who did not pause their BTKi. However, the response was attenuated after BTKi recommencement. This data contributes to our understanding of vaccination strategies in this patient group and may help inform consensus approaches in the future.

Vaccinations in hematological patients in the era of target therapies: Lesson learnt from SARS-CoV-2

Novel targeting agents for hematologic diseases often exert on- or off-target immunomodulatory effects, possibly impacting on response to anti-SARS-CoV-2 vaccinations and other vaccines. Agents that primarily affect B cells, particularly anti-CD20 monoclonal antibodies (MoAbs), Bruton tyrosine kinase inhibitors, and anti-CD19 chimeric antigen T-cells, have the strongest impact on seroconversion. JAK2, BCL-2 inhibitors and hypomethylating agents may hamper immunity but show a less prominent effect on humoral response to vaccines. Conversely, vaccine efficacy seems not impaired by anti-myeloma agents such as proteasome inhibitors and immunomodulatory agents, although lower seroconversion rates are observed with anti-CD38 and anti-BCMA MoAbs. Complement inhibitors for complement-mediated hematologic diseases and immunosuppressants used in aplastic anemia do not generally affect seroconversion rate, but the extent of the immune response is reduced under steroids or anti-thymocyte globulin. Vaccination is recommended prior to treatment or as far as possible from anti-CD20 MoAb (at least 6 months). No clearcut indications for interrupting continuous treatment emerged, and booster doses significantly improved seroconversion. Cellular immune response appeared preserved in several settings.

A false positive serology test of SARS‑CoV‑2 in a patient with Waldenström's macroglobulinemia: A case report

The serology test of SARS-CoV-2 is one of the critical assays to make a diagnosis of SARS-CoV-2 infection. The gold immunochromatography assay (GICA) is a common measure to test SARS-CoV-2 specific IgG and IgM. The sensitivity and specificity of the assay are ~>80%. It has been reported that the result of GICA could be compromised in various situations, such as auto-immune diseases, Kawasaki disease, pregnancy or other conditions. However, following the European Hematology Association's consensus statement on the management of Waldenström's Macroglobulinemia (WM) patients, serological tests for SARS-CoV-2 specific IgM should not be affected by the total IgM or paraprotein levels. The present study reports a patient with duplicate positive serology tests of SARS-CoV-2 which is hypothesized to be due to monoclonal IgM caused by WM.

Adult Patients with Cancer Have Impaired Humoral Responses to Complete and Booster COVID-19 Vaccination, Especially Those with Hematologic Cancer on Active Treatment: A Systematic Review and Meta-Analysis

The exclusion of patients with cancer in clinical trials evaluating COVID-19 vaccine efficacy and safety, in combination with the high rate of severe infections, highlights the need for optimizing vaccination strategies. The aim of this study was to perform a systematic review and meta-analysis of the published available data from prospective and retrospective cohort studies that included patients with either solid or hematological malignancies according to the PRISMA Guidelines. A literature search was performed in the following databases: Medline (Pubmed), Scopus, Clinicaltrials.gov, EMBASE, CENTRAL and Google Scholar. Overall, 70 studies were included for the first and second vaccine dose and 60 studies for the third dose. The Effect Size (ES) of the seroconversion rate after the first dose was 0.41 (95%CI: 0.33-0.50) for hematological malignancies and 0.56 (95%CI: 0.47-0.64) for solid tumors. The seroconversion rates after the second dose were 0.62 (95%CI: 0.57-0.67) for hematological malignancies and 0.88 (95%CI: 0.82-0.93) for solid tumors. After the third dose, the ES for seroconversion was estimated at 0.63 (95%CI: 0.54-0.72) for hematological cancer and 0.88 (95%CI: 0.75-0.97) for solid tumors. A subgroup analysis was performed to evaluate potential factors affecting immune response. Production of anti-SARS-CoV-2 antibodies was found to be more affected in patients with hematological malignancies, which was attributed to the type of malignancy and treatment with monoclonal antibodies according to the subgroup analyses. Overall, this study highlights that patients with cancer present suboptimal humoral responses after COVID-19 vaccination. Several factors including timing of vaccination in relevance with active therapy, type of therapy, and type of cancer should be considered throughout the immunization process.

Report of consensus panel 1 from the 11th International Workshop on Waldenstrom's Macroglobulinemia on management of symptomatic, treatment-naïve patients

Consensus Panel 1 (CP1) of the 11th International Workshop on Waldenstrom's Macroglobulinemia (IWWM-11) was tasked with updating guidelines for the management of symptomatic, treatment-naïve patients with WM. The panel reiterated that watchful waiting remains the gold standard for asymptomatic patients without critically elevated IgM or compromised hematopoietic function. For first-line treatment, chemoimmunotherapy (CIT) regimens such as dexamethasone, cyclophosphamide, rituximab (DRC), or bendamustine, rituximab (Benda-R) continue to play a central role in managing WM, as they are effective, of fixed duration, generally well-tolerated, and affordable. Covalent BTK inhibitors (cBTKi) offer a continuous, generally well-tolerated alternative for the primary treatment of WM patients, particularly those unsuitable for CIT. In a Phase III randomized trial updated at IWWM-11, the second-generation cBTKi, zanubrutinib, was less toxic than ibrutinib and induced deeper remissions, thus categorizing zanubrutinib as a suitable treatment option in WM. While the overall findings of a prospective, randomized trial updated at IWWM-11 did not show superiority of fixed duration rituximab maintenance over observation following attainment of a major response to Benda-R induction, a subset analysis showed benefit in patients >65 years and those with a high IPPSWM score. Whenever possible, the mutational status of MYD88 and CXCR4 should be determined before treatment initiation, as alterations in these 2 genes predict sensitivity towards cBTKi activity. Treatment approaches for WM-associated cryoglobulins, cold agglutinins, AL amyloidosis, Bing-Neel syndrome (BNS), peripheral neuropathy, and hyperviscosity syndrome follow the common principle of reducing tumor and abnormal protein burden rapidly and deeply to improve symptoms. In BNS, ibrutinib can be highly active and produce durable responses. In contrast, cBTKi are not recommended for treating AL amyloidosis. The panel emphasized that continuous improvement of treatment options for symptomatic, treatment-naïve WM patients critically depends on the participation of patients in clinical trials, whenever possible.

Report of consensus panel 5 from the 11th international workshop on Waldenstrom's macroglobulinemia on COVID-19 prophylaxis and management

Consensus Panel 5 (CP5) of the 11th International Workshop on Waldenstrom's Macroglobulinemia (IWWM-11; held in October 2022) was tasked with reviewing the current data on the coronavirus disease-2019 (COVID-19) prophylaxis and management in patients with Waldenstrom's Macroglobulinemia (WM). The key recommendations from IWWM-11 CP5 included the following: Booster vaccines for SARS-CoV-2 should be recommended to all patients with WM. Variant-specific booster vaccines, such as the bivalent vaccine for the ancestral Wuhan strain and the Omicron BA.4.5 strain, are important as novel mutants emerge and become dominant in the community. A temporary interruption in Bruton's Tyrosine Kinase-inhibitor (BTKi) or chemoimmunotherapy before vaccination might be considered. Patients under treatment with rituximab or BTK-inhibitors have lower antibody responses against SARS-CoV-2; thus, they should continue to follow preventive measures, including mask wearing and avoiding crowded places. Patients with WM are candidates for preexposure prophylaxis, if available and relevant to the dominant SARS-CoV-2 strains in a specific area. Oral antivirals should be offered to all symptomatic WM patients with mild to moderate COVID-19 regardless of vaccination, disease status or treatment, as soon as possible after the positive test and within 5 days of COVID-19-related symptom onset. Coadministration of ibrutinib or venetoclax with ritonavir should be avoided. In these patients, remdesivir offers an effective alternative. Patients with asymptomatic or oligosymptomatic COVID-19 should not interrupt treatment with a BTK inhibitor. Infection prophylaxis is essential in patients with WM and include general preventive measures, prophylaxis with antivirals and vaccination against common pathogens including SARS-CoV-2, influenza, and S. pneumoniae.

Immunogenicity of COVID-19 mRNA vaccines in patients with acute myeloid leukemia and myelodysplastic syndrome

Immunocompromised patients are susceptible to complications from severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). The mRNA vaccines BNT162b2 and mRNA-1273 are effective in immunocompetent adults, but have diminished activity in immunocompromised patients. We measured anti-spike SARS-CoV-2 antibody (anti-S) response, avidity, and surrogate neutralizing antibody activity in COVID-19 vaccinated patients with acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS). Anti-S was induced in 89% of AML and 88% of MDS patients, but median levels were significantly lower than in healthy controls. SARS-CoV-2 antibody avidity and neutralizing activity from AML patients were significantly lower than controls. Antibody avidity was significantly greater in patients after mRNA-1273 versus BNT162b2; there were trends toward higher anti-S levels and greater neutralizing antibody activity after mRNA-1273 vaccination. Patients with AML and MDS are likely to respond to COVID-19 mRNA vaccination, but differences in anti-S levels, avidity, and neutralizing antibody activity may affect clinical outcomes and require further study.

Score to assess the probability of relapse in granulomatosis with polyangiitis and microscopic polyangiitis

OBJECTIVE

To develop a score assessing the probability of relapse in granulomatosis with polyangiitis (GPA) and microscopic polyangiitis (MPA).

METHODS

Long-term follow-up data from GPA and MPA patients included in five consecutive randomised controlled trials were pooled. Patient characteristics at diagnosis were entered into a competing-risks model, with relapse as the event of interest and death the competing event. Univariate and multivariate analyses were computed to identify variables associated with relapse and build a score, which was then validated in an independent cohort of GPA or MPA patients.

RESULTS

Data collected from 427 patients (203 GPA, 224 MPA) at diagnosis were included. Mean±SD follow-up was 80.6±51.3 months; 207 (48.5%) patients experienced ≥1 relapse. Relapse risk was associated with proteinase 3 (PR3) positivity (HR=1.81 (95% CI 1.28 to 2.57); p<0.001), age ≤75 years (HR=1.89 (95% CI 1.15 to 3.13); p=0.012) and estimated glomerular filtration rate (eGFR) ≥30 mL/min/1.73 m² (HR=1.67 (95% CI 1.18 to 2.33); p=0.004) at diagnosis. A score, the French Vasculitis Study Group Relapse Score (FRS), from 0 to 3 points was modelised: 1 point each for PR3-antineutrophil cytoplasmic antibody positivity, eGFR ≥30 mL/min/1.73 m² and age ≤75 years. In the validation cohort of 209 patients, the 5-year relapse risk was 8% for a FRS of 0, 30% for 1, 48% for 2 and 76% for 3.

CONCLUSION

The FRS can be used at diagnosis to assess the relapse risk in patients with GPA or MPA. Its value for tailoring the duration of maintenance therapy should be evaluated in future prospective trials.

Response to COVID-19 vaccination post CAR T therapy in patients with non-Hodgkin lymphoma and multiple myeloma

COVID-19 adversely affects individuals with cancer. Several studies have found that seroconversion rates among patients with hematologic malignancies are suboptimal when compared to patients without cancer. Patients with non-Hodgkin lymphoma (NHL) and multiple myeloma (MM) are immunocompromised due to impaired humoral and cellular immunity in addition to prescribed immunosuppressive therapy. Chimeric antigen receptor T-cell (CAR T) therapy is now widely used for NHL and MM, but little is known about seroconversion rates after COVID-19 vaccination among these populations. We evaluated SARS-CoV-2 spike-binding IgG antibody levels following COVID-19 vaccination among NHL and MM CAR T therapy recipients. Out of 104 CAR T infusions, 19 patients developed known COVID-19 infection post-CAR T. We tested 17 patients that received CAR T for antibody spike titers post COVID-19 vaccination, only 29 % (n = 5) were able to mount a clinically relevant antibody response (>250 IU/mL).

Clinical usefulness of testing for severe acute respiratory syndrome coronavirus 2 antibodies

In the COVID-19 pandemic era, antibody testing against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has proven an invaluable tool and herein we highlight some of the most useful clinical and/or epidemiological applications of humoral immune responses recording. Anti-spike circulating IgGs and SARS-CoV-2 neutralizing antibodies can serve as predictors of disease progression or disease prevention, whereas anti-nucleocapsid antibodies can help distinguishing infection from vaccination. Also, in the era of immunotherapies we address the validity of anti-SARS-CoV-2 antibody monitoring post-infection and/or vaccination following therapies with the popular anti-CD20 monoclonals, as well as in the context of various cancers or autoimmune conditions such as rheumatoid arthritis and multiple sclerosis. Additional crucial applications include population immunosurveillance, either at the general population or at specific communities such as health workers. Finally, we discuss how testing of antibodies in cerebrospinal fluid can inform us on the neurological complications that often accompany COVID-19.

Anti-RBD IgG antibodies and neutralizing antibody levels after the second BNT162b2 dose in patients with plasma cell disorders

Patients with plasma cell disorders (PCD) are at an increased risk for severe morbidity and mortality due to COVID-19. Recent data have suggested that patients with hematological malignancies, including those with PCD, have suboptimal antibody response to COVID-19 vaccination. We compared the antibody titers of 213 patients with PCD to those of 213 immunocompetent healthcare workers after the second vaccine dose of the BNT162b2 mRNA vaccine. Blood samples were taken 2-4 weeks after the second vaccination and analyzed for anti-receptor binding-domain immunoglobulin G (RBD-IgG) antibodies and neutralizing antibodies (NA). At a median of 20 days after the second vaccine dose, 172 patients (80.8%) developed anti-RBD-IgG antibodies with a geometric mean titer (GMT) of 2.7 (95% confidence interval [CI], 2.4-3.1). In the control group 210 (98.9%) developed anti-RBD-IgG antibodies after a median of 21 days, with a GMT of 5.17 (95%CI, 4.8-5.6), p<0.0001. NA were observed in 151 patients with MM (70.9%) and in 210 controls (98.9%). The GMT of NA in patients with MM and controls was 84.4 (95% CI, 59.0-120.6), and 420.2 (95% CI, 341.4-517.1), respectively (p<0.0001). Multivariable logistic regression revealed that the number of prior therapy lines and age were significant predictors of poor humoral response among patients with MM. Injection site reaction, headache and fatigue were the most common adverse events after vaccination. Adverse events were less common in patients with MM than in controls. In conclusion, a significant percentage of patients with MM developed protecting NA to the BNT162b2 mRNA vaccine, which appears to be safe in this patient population.

Immunogenicity and risks associated with impaired immune responses following SARS-CoV-2 vaccination and booster in hematologic malignancy patients: an updated meta-analysis

Patients with hematologic malignancies (HM) have demonstrated impaired immune responses following SARS-CoV-2 vaccination. Factors associated with poor immunogenicity remain largely undetermined. A literature search was conducted using PubMed, EMBASE, Cochrane, and medRxiv databases to identify studies that reported humoral or cellular immune responses (CIR) following complete SARS-CoV-2 vaccination. The primary aim was to estimate the seroconversion rate (SR) following complete SARS-CoV-2 vaccination across various subtypes of HM diseases and treatments. The secondary aims were to determine the rates of development of neutralizing antibodies (NAb) and CIR following complete vaccination and SR following booster doses. A total of 170 studies were included for qualitative and quantitative analysis of primary and secondary outcomes. A meta-analysis of 150 studies including 20,922 HM patients revealed a pooled SR following SARS-CoV-2 vaccination of 67.7% (95% confidence interval [CI], 64.8-70.4%; I² = 94%). Meta-regression analysis showed that patients with lymphoid malignancies, but not myeloid malignancies, had lower seroconversion rates than those with solid cancers (R² = 0.52, P < 0.0001). Patients receiving chimeric antigen receptor T-cells (CART), B-cell targeted therapies or JAK inhibitors were associated with poor seroconversion (R² = 0.39, P < 0.0001). The pooled NAb and CIR rates were 52.8% (95% CI; 45.8-59.7%, I² = 87%) and 66.6% (95% CI, 57.1-74.9%; I² = 86%), respectively. Approximately 20.9% (95% CI, 11.4-35.1%, I² = 90%) of HM patients failed to elicit humoral and cellular immunity. Among non-seroconverted patients after primary vaccination, only 40.5% (95% CI, 33.0-48.4%; I² = 87%) mounted seroconversion after the booster. In conclusion, HM patients, especially those with lymphoid malignancies and/or receiving CART, B-cell targeted therapies, or JAK inhibitors, showed poor SR after SARS-CoV-2 vaccination. A minority of patients attained seroconversion after booster vaccination. Strategies to improve immune response in these severely immunosuppressed patients are needed.

Low Spike Antibody Levels and Impaired BA.4/5 Neutralization in Patients with Multiple Myeloma or Waldenstrom's Macroglobulinemia after BNT162b2 Booster Vaccination

Patients with symptomatic monoclonal gammopathies have impaired humoral responses to COVID-19 vaccination. Their ability to recognize SARS-CoV-2 Omicron variants is of concern. We compared the response to BNT162b2 mRNA vaccinations of patients with multiple myeloma (MM, n = 60) or Waldenstrom's macroglobulinemia (WM, n = 20) with healthy vaccine recipients (n = 37). Patient cohorts on active therapy affecting B cell development had impaired binding and neutralizing antibody (NAb) response rate and magnitude, including several patients lacking responses, even after a 3rd vaccine dose, whereas non-B cell depleting therapies had a lesser effect. In contrast, MM and WM cohorts off-therapy showed increased NAb with a broad response range. ELISA Spike-Receptor Binding Domain (RBD) Ab titers in healthy vaccine recipients and patient cohorts were good predictors of the ability to neutralize not only the original WA1 but also the most divergent Omicron variants BA.4/5. Compared to WA1, significantly lower NAb responses to BA.4/5 were found in all patient cohorts on-therapy. In contrast, the MM and WM cohorts off-therapy showed a higher probability to neutralize BA.4/5 after the 3rd vaccination. Overall, the boost in NAb after the 3rd dose suggests that repeat vaccination of MM and WM patients is beneficial even under active therapy.

Anemia - an initial manifestation of Bing-Neel syndrome: A case report

RATIONALE

It is very likely that we will miss Bing-Neel syndrome (BNS) when its initial sign is anemia.Patient concerns: A 59-year-old woman presented with episodic loss of consciousness, anemia, and extremity muscle strength scores (5-) and extremity tendon reflexes (++).

DIAGNOSES

Magnetic Resonance Imaging (MRI) showed abnormal signal in the left hippocampus, left insula, and right occipital lobe. Quantitative serum immunoglobulins showed elevated immunoglobulinm (IgM) (60.6g/L). Bone marrow biopsy showed lymphoplasmacytic lymphoma (LPL) and tested positive for the MYD88 L265P mutation suggesting Waldenström macroglobulinemia (WM).

INTERVENTIONS

The patient underwent 3 plasma exchange treatments in the department of hematology followed by chemotherapy (cyclophosphamide for injection, bortezomib for injection).

OUTCOMES

The patient's condition improved after treatment.

LESSONS

Clinicians must remain vigilant, as BNS may be the only sign of WM progression in a patient well-controlled on treatment.

The Four Ws of the Fourth Dose COVID-19 Vaccines: Why, Who, When and What

With the emergence of SARS-CoV-2 variants, vaccine breakthrough is a major public health concern. With evidence of reduced neutralizing antibody activity against Omicron variants and fading antibody level after the third-dose booster vaccine, there are suggestions of a fourth-dose booster vaccine. In this review, the benefits of a fourth-dose booster is evaluated from four perspectives, including the effectiveness of the booster dose against virus variants (Why), susceptible groups of individuals who may benefit from additional booster dose (Who), selection of vaccine platforms to better enhance immunity (What) and appropriate intervals between the third and fourth booster dose (When). In summary, a fourth dose can temporarily boost the immune response against SARS-CoV-2 variants and can be considered for specific groups of individuals. A heterologous vaccine strategy using mRNA vaccine in individuals primed with inactivated vaccine may boost immunity against variants. The timing of the fourth dose should be individualized but an interval of 4 months after the third-dose booster is appropriate. A universal fourth booster dose is not necessary.

Efficacy of COVID-19 Booster Vaccines in Patients with Hematologic Malignancies: Experiences in a Real-World Scenario

Background: Two-dose COVID-19 vaccination often results in poor humoral response rates in patients with hematologic malignancies (HMs); yet responses to COVID-19 booster vaccines and the risk of COVID-19 infection post-booster are mostly uncertain. Methods: We included 200 outpatients with HMs and predominantly lymphoid neoplasms (96%, 191/200) in our academic center and reported on the humoral responses, which were assessed by measurement of anti-spike IgG antibodies in peripheral blood as early as 14 days after mRNA-based prime-boost vaccination, as well as factors hampering booster efficacy. Previous basic (double) immunization was applied according to the local recommendations with mRNA- and/or vector-based vaccines. We also report on post-booster COVID-19 breakthrough infections that emerged in the Omicron era and the prophylaxis strategies that were applied to poor and non-responders to booster vaccines. Results: A total of 55% (110/200) of the patients achieved seroconversion (i.e., anti-spike protein IgG antibody titer > 100 AU/mL assessed in median 48 days after prime-boost vaccination) after prime-boost vaccination. Multivariable analyses revealed age, lymphocytopenia, ongoing treatment and prior anti-CD20 B-cell depletion to be independent predictors for booster failure. With each month between anti-CD20-mediated B-cell depletion and booster vaccination, the probability of seroconversion increased by approximately 4% (p < 0.001) and serum−antibody titer (S-AbT) levels increased by 90 AU/mL (p = 0.011). Notably, obinutuzumab treatment was associated with an 85% lower probability for seroconversion after prime-boost vaccination compared to rituximab (p = 0.002). Of poor or non-responders to prime-boost vaccination, 41% (47/114) underwent a second booster and 73% (83/114) underwent passive immunization. COVID-19 breakthrough infections were observed in 15% (29/200) of patients after prime-boost vaccination with predominantly mild courses (93%). Next to seroconversion, passive immunization was associated with a significantly lower risk of COVID-19 breakthrough infections after booster, even in vaccine non-responders (all p < 0.05). In a small proportion of analyzed patients with myeloid neoplasms (9/200), the seroconversion rate was higher compared to those with lymphoid ones (78% vs. 54%, accordingly), while the incidence rate of COVID-19 breakthrough infections was similar (22% vs. 14%, respectively). Following the low frequency of myeloid neoplasms in this study, the results may not be automatically applied to a larger cohort. Conclusions: Patients with HMs are at a high risk of COVID-19 booster vaccine failure; yet COVID-19 breakthrough infections after prime-boost vaccination are predominantly mild. Booster failure can likely be overcome by passive immunization, thereby providing immune protection against COVID-19 and attenuating the severity of COVID-19 courses. Further sophistication of clinical algorithms for preventing post-vaccination COVID-19 breakthrough infections is urgently needed.

The current status of COVID-19 vaccines. A scoping review

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a new disease that has led to a worldwide pandemic, resulting in millions of deaths and a high economic burden. Here, we analyze the current status of preventive vaccines authorized by the European Medicines Agency (EMA) and the US Food and Drug Administration (FDA). Published clinical trials have shown the effectiveness of mRNA (BNT162b2 and Spikevax), adenovirus vector-based (Ad26.COV2.S and ChAdOx1 nCoV-19), and recombinant protein S (NVX-CoV2373) vaccines to be between 52.9% and 100%. The most-frequent adverse effects include local pain, fatigue, headache, or chills. Serious events are associated with Ad26.COV2.S and ChAdOx1 nCoV-19 vaccines.

Chronic cold agglutinin disease after a third COVID-19 mRNA vaccination

COVID-19 mRNA vaccines manufactured by Pfizer-BioNTech and Moderna have been approved in many countries, and have been administered since 2020. Recent reports of mRNA vaccination exacerbating autoimmune hematologic disorders, such as immune thrombocytopenia or autoimmune hemolytic anemia, have caught the attention of the general public, resulting in alarm over the risks of serious consequences. Meanwhile, in very rare cases, vaccination was reported to trigger new onset of hemolytic anemia. However, it remains unknown whether this was a transient reaction or a persistent event, because all cases reported to date were immediately treated with corticosteroids or rituximab. Here, we present a case of newly diagnosed cold agglutinin disease after a third COVID-19 mRNA vaccination. The patient was followed for 4 months without treatment and continued to exhibit high levels of cold agglutinin and aggregation of red blood cells. The present case indicates that the disease can become chronic, and provides insights into the pathogenesis and treatment strategies.

SARS-CoV-2 humoral responses following booster BNT162b2 vaccination in patients with B-cell malignancies

Patients with B-cell malignancies have suboptimal immune responses to SARS-CoV-2 vaccination and are a high-risk population for severe COVID19 disease. We evaluated the effect of a third booster BNT162b2 vaccine on the kinetics of anti- SARS-CoV-2 neutralizing antibody (NAbs) titers in patients with B-cell malignancies. Patients with NHL (n = 54) Waldenström's macroglobulinemia (n = 90) and chronic lymphocytic leukemia (n = 49) enrolled in the ongoing NCT04743388 study and compared against matched healthy controls. All patient groups had significantly lower NAbs compared to controls at all time points. 1 month post the third dose (M1P3D) NAbs increased significantly compared to previous time points (median NAbs 77.9%, p < .05 for all comparisons) in all patients. NAbs ≥ 50% were seen in 59.1% of patients, 34.5% of patients with suboptimal responses post-second dose, elicited a protective NAb titer ≥50%. Active treatment, rituximab, and BTKi treatment were the most important prognostic factors for a poor NAb response at 1MP3D; only 25.8% of patients on active treatment had NAbs ≥ 50%. No significant between-group differences were observed. Patients with B-cell malignancies have inferior humoral responses against SARS-CoV-2 and booster dose enhances the NAb response in a proportion of these patients.

A Cellular Assay for Spike/ACE2 Fusion: Quantification of Fusion-Inhibitory Antibodies after COVID-19 and Vaccination

Not all antibodies against SARS-CoV-2 inhibit viral entry, and hence, infection. Neutralizing antibodies are more likely to reflect real immunity; however, certain tests investigate protein/protein interaction rather than the fusion event. Viral and pseudoviral entry assays detect functionally active antibodies but are limited by biosafety and standardization issues. We have developed a Spike/ACE2-dependent fusion assay, based on a split luciferase. Hela cells stably transduced with Spike and a large fragment of luciferase were co-cultured with Hela cells transduced with ACE2 and the complementary small fragment of luciferase. Cell fusion occurred rapidly allowing the measurement of luminescence. Light emission was abolished in the absence of Spike and reduced in the presence of proteases. Sera from COVID-19-negative, non-vaccinated individuals or from patients at the moment of first symptoms did not lead to a significant reduction of fusion. Sera from COVID-19-positive patients as well as from vaccinated individuals reduced the fusion. This assay was more correlated to pseudotyped-based entry assay rather than serology or competitive ELISA. In conclusion, we report a new method measuring fusion-inhibitory antibodies in serum, combining the advantage of a complete Spike/ACE2 interaction active on entry with a high degree of standardization, easily allowing automation in a standard bio-safety environment.

A systematic review and meta-analysis of immune response against first and second doses of SARS-CoV-2 vaccines in adult patients with hematological malignancies

BACKGROUND

Cancer patients particularly those with hematological malignancies are at higher risk of affecting by severe coronavirus disease 2019 (COVID-19). Due to the immunocompromised nature of the disease and the immunosuppressive treatments, they are more likely to develop less antibody protection; therefore, we aimed to evaluate the immunogenicity of COVID-19 vaccines in patients with hematological malignancies.

METHODS

A comprehensive systematic search was conducted in PubMed, Scopus, and Web of Science databases, as well as Google scholar search engine as of December 10, 2021. Our primary outcomes of interest comprised of estimating the antibody seropositive rate following COVID-19 vaccination in patients with hematological malignancies and to compare it with those who were affected by solid tumors or healthy subjects. The secondary outcomes were to assess the vaccine's immunogenicity based on different treatments, status of the disease, and type of vaccine. After the two-step screening, the data were extracted and the summary measures were calculated using a random-effect model.

RESULTS

A total of 82 articles recording 13,804 patients with a diagnosis of malignancy were included in the present review. The seropositive rates in patients with hematological malignancies after first and second vaccine doses were 30.0% (95% confidence interval (95%CI): 11.9-52.0) and 62.3% (95%CI 56.0-68.5), respectively. These patients were less likely to develop antibody response as compared to cases with solid tumors (RR 0.73, 95%CI 0.67-0.79) and healthy subjects (RR 0.62, 95%CI 0.54-0.71) following complete immunization. Chronic lymphocytic leukemia (CLL) patients had the lowest response rate among all subtypes of hematological malignancies (first dose: 22.0%, 95%CI 13.5-31.8 and second dose: 47.8%, 95%CI 41.2-54.4). Besides, anti-CD20 therapies (5.7%, 95%CI 2.0-10.6) and bruton's tyrosine kinase inhibitors (26.8%, 95%CI 16.9-37.8) represented the lowest seropositiveness post first and second doses, respectively. Notably, patients who were in active status of disease showed lower antibody detection rate compared to those on remission status (RR 0.87, 95%CI 0.76-0.99). Furthermore, lower rate of seropositivity was found in patients received BNT162.b2 compared to ones who received mRNA-1273 (RR 0.89, 95%CI 0.79-0.99).

CONCLUSION

Our findings highlight the substantially low rate of seroprotection in patients with hematological malignancies with a wide range of rates among disease subgroups and different treatments; further highlighting the fact that booster doses might be acquired for these patients to improve immunity against SARS-CoV-2.

Efficacy and safety profile of COVID-19 mRNA vaccine in patients with hematological malignancies: Systematic review and meta-analysis

Patient populations, including those with hematological malignancies, have different responses to COVID-19 vaccines. This study aimed to quantitatively analyze the efficacy and safety of COVID-19 mRNA vaccines in patients with hematological malignancies. Studies reporting on the efficacy and safety of COVID-19 mRNA vaccines in cohorts with hematological malignancies compared to healthy controls were systematically searched in four databases. Meta-analysis and subgroup analyses were performed to generate quantitative synthesis. Fifteen studies with 2,055 cohorts with hematological malignancies and 1,105 healthy subjects as control were included. After two doses of COVID-19 vaccination, only 60% of cohorts with hematological malignancies were seroconverted compared to healthy controls (RR 0.60; 95%CI 0.50–0.71). A single dose of the vaccine resulted in a significantly lower seroconversion rate (RR 0.30; 95%CI 0.16–0.54). Non-Hodgkin lymphoma cohorts had the lowest rate of seroconversion (RR 0.5; 95%CI 0.35–0.71) and those who received active treatments had lower immunological responses (RR 0.59; 95%CI 0.46–0.75). Antibody titers were lower in cohorts with hematological malignancies without any differences in adverse effects in both groups. In conclusion, cohorts with hematological malignancies showed a lower seroconversion rate and antibody titers after receiving COVID-19 mRNA vaccines. The type of malignancy and the status of treatment had a significant impact on the response to vaccination. The vaccines were shown to be safe for both patients with hematological malignancies and healthy controls. Booster doses and stricter health protocols might be beneficial for patient populations.

COVID-19 mRNA Vaccine in Patients With Lymphoid Malignancy or Anti-CD20 Antibody Therapy: A Systematic Review and Meta-Analysis

BACKGROUND

The humoral response to vaccination in individuals with lymphoid malignancies or those undergoing anti-CD20 antibody therapy is impaired, but details of the response to mRNA vaccines to protect against COVID-19 remain unclear. This systematic review and meta-analysis aimed to characterize the response to COVID-19 mRNA vaccines in patients with lymphoid malignancies or those undergoing anti-CD20 antibody therapy.

MATERIALS AND METHODS

A literature search retrieved 52 relevant articles, and random-effect models were used to analyze humoral and cellular responses.

RESULTS

Lymphoid malignancies and anti-CD20 antibody therapy for non-malignancies were significantly associated with lower seropositivity rates (risk ratio 0.60 [95% CI 0.53-0.69]; risk ratio 0.45 [95% CI 0.39-0.52], respectively). Some subtypes (chronic lymphocytic leukemia, treatment-naïve chronic lymphocytic leukemia, myeloma, and non-Hodgkin's lymphoma) exhibited impaired humoral response. Anti-CD20 antibody therapy within 6 months of vaccination decreased humoral response; moreover, therapy > 12 months before vaccination still impaired the humoral response. However, anti-CD20 antibody therapy in non-malignant patients did not attenuate T cell responses.

CONCLUSION

These data suggest that patients with lymphoid malignancies or those undergoing anti-CD20 antibody therapy experience an impaired humoral response, but cellular response can be detected independent of anti-CD20 antibody therapy. Studies with long-term follow-up of vaccine effectiveness are warranted (PROSPERO registration number: CRD42021265780).

Reduced Antibodies and Innate Cytokine Changes in SARS-CoV-2 BNT162b2 mRNA Vaccinated Transplant Patients With Hematological Malignancies

Immunocompromised individuals including patients with hematological malignancies constitute a population at high risk of developing severe disease upon SARS-CoV-2 infection. Protection afforded by vaccination is frequently low and the biology leading to altered vaccine efficacy is not fully understood. A patient cohort who had received bone marrow transplantation or CAR-T cells was studied following a 2-dose BNT162b2 mRNA vaccination and compared to healthy vaccine recipients. Anti-Spike antibody and systemic innate responses were compared in the two vaccine cohorts. The patients had significantly lower SARS-CoV-2 Spike antibodies to the Wuhan strain, with proportional lower cross-recognition of Beta, Delta, and Omicron Spike-RBD proteins. Both cohorts neutralized the wildtype WA1 and Delta but not Omicron. Vaccination elicited an innate cytokine signature featuring IFN-γ, IL-15 and IP-10/CXCL10, but most patients showed a diminished systemic cytokine response. In patients who failed to develop antibodies, the innate systemic response was dominated by IL-8 and MIP-1α with significant attenuation in the IFN-γ, IL-15 and IP-10/CXCL10 signature response. Changes in IFN-γ and IP-10/CXCL10 at priming vaccination and IFN-γ, IL-15, IL-7 and IL-10 upon booster vaccination correlated with the Spike antibody magnitude and were predictive of successful antibody development. Overall, the patients showed heterogeneous adaptive and innate responses with lower humoral and reduced innate cytokine responses to vaccination compared to naïve vaccine recipients. The pattern of responses described offer novel prognostic approaches for potentiating the effectiveness of COVID-19 vaccination in transplant patients with hematological malignancies.

Early Cellular and Humoral Responses Developed in Oncohematological Patients after Vaccination with One Dose against COVID-19

Individuals with oncohematological diseases (OHD) may develop an impaired immune response against vaccines due to the characteristics of the disease or to its treatment. Humoral response against SARS-CoV-2 has been described to be suboptimal in these patients, but the quality and efficiency of the cellular immune response has not been yet completely characterized. In this study, we analyzed the early humoral and cellular immune responses in individuals with different OHD after receiving one dose of an authorized vaccine against SARS-CoV-2. Humoral response, determined by antibodies titers and neutralizing capacity, was overall impaired in individuals with OHD, except for the cohort of chronic myeloid leukemia (CML), which showed higher levels of specific IgGs than healthy donors. Conversely, the specific direct cytotoxic cellular immunity response (DCC) against SARS-CoV-2, appeared to be enhanced, especially in individuals with CML and chronic lymphocytic leukemia (CLL). This increased cellular immune response, developed earlier than in healthy donors, showed a modest cytotoxic activity that was compensated by significantly increased numbers, likely due to the disease or its treatment. The analysis of the immune response through subsequent vaccine doses will help establish the real efficacy of COVID-19 vaccines in individuals with OHD.

Detecting SARS-CoV-2 neutralizing immunity: highlighting the potential of split nanoluciferase technology

The coronavirus disease 2019 (COVID-19) pandemic has progressed over 2 years since its onset causing significant health concerns all over the world and is currently curtailed by mass vaccination. Immunity acquired against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can be following either infection or vaccination. However, one can never be sure whether the acquired immunity is adequate to protect the individual from subsequent infection because of three important factors: individual variations in humoral response dynamics, waning of protective antibodies over time, and the emergence of immune escape mutants. Therefore, a test that can accurately differentiate the protected from the vulnerable is the need of the hour. The plaque reduction neutralization assay is the conventional gold standard test for estimating the titers of neutralizing antibodies that confer protection. However, it has got several drawbacks, which hinder the practical application of this test for wide-scale usage. Hence, various tests have been developed to detect protective immunity against SARS-CoV-2 that directly or indirectly assess the presence of neutralizing antibodies to SARS-CoV-2 in a lower biosafety setting. In this review, the pros and cons of the currently available assays are elaborated in detail and special focus is put on the scope of the novel split nanoluciferase technology for detecting SARS-CoV-2 neutralizing antibodies.

Patients recently treated for B-lymphoid malignancies show increased risk of severe COVID-19: a CCC19 registry analysis

Patients with B-lymphoid malignancies have been consistently identified as a population at high risk of severe COVID-19. Whether this is exclusively due to cancer-related deficits in humoral and cellular immunity, or whether risk of severe COVID-19 is increased by anti-cancer therapy, is uncertain. Using data derived from the COVID-19 and Cancer Consortium (CCC19), we show that patients treated for B-lymphoid malignancies have an increased risk of severe COVID-19 compared to control populations of patients with non-B-lymphoid hematologic malignancies. Among patients with B-lymphoid malignancies, those who received anti-cancer therapy within 12 months of COVID-19 diagnosis experienced increased COVID-19 severity compared to patients with B-lymphoid malignancies off therapy, after adjustment for cancer status and several other prognostic factors. Our findings suggest that patients recently treated for a B-lymphoid malignancy are at uniquely high risk for severe COVID-19.

Efficacy of covid-19 vaccines in immunocompromised patients: systematic review and meta-analysis

OBJECTIVE

To compare the efficacy of covid-19 vaccines between immunocompromised and immunocompetent people.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

PubMed, Embase, Central Register of Controlled Trials, COVID-19 Open Research Dataset Challenge (CORD-19), and WHO covid-19 databases for studies published between 1 December 2020 and 5 November 2021. ClinicalTrials.gov and the WHO International Clinical Trials Registry Platform were searched in November 2021 to identify registered but as yet unpublished or ongoing studies.

STUDY SELECTION

Prospective observational studies comparing the efficacy of covid-19 vaccination in immunocompromised and immunocompetent participants.

METHODS

A frequentist random effects meta-analysis was used to separately pool relative and absolute risks of seroconversion after the first and second doses of a covid-19 vaccine. Systematic review without meta-analysis of SARS-CoV-2 antibody titre levels was performed after first, second, and third vaccine doses and the seroconversion rate after a third dose. Risk of bias and certainty of evidence were assessed.

RESULTS

82 studies were included in the meta-analysis. Of these studies, 77 (94%) used mRNA vaccines, 16 (20%) viral vector vaccines, and 4 (5%) inactivated whole virus vaccines. 63 studies were assessed to be at low risk of bias and 19 at moderate risk of bias. After one vaccine dose, seroconversion was about half as likely in patients with haematological cancers (risk ratio 0.40, 95% confidence interval 0.32 to 0.50, I²=80%; absolute risk 0.29, 95% confidence interval 0.20 to 0.40, I²=89%), immune mediated inflammatory disorders (0.53, 0.39 to 0.71, I²=89%; 0.29, 0.11 to 0.58, I²=97%), and solid cancers (0.55, 0.46 to 0.65, I²=78%; 0.44, 0.36 to 0.53, I²=84%) compared with immunocompetent controls, whereas organ transplant recipients were 16 times less likely to seroconvert (0.06, 0.04 to 0.09, I²=0%; 0.06, 0.04 to 0.08, I²=0%). After a second dose, seroconversion remained least likely in transplant recipients (0.39, 0.32 to 0.46, I²=92%; 0.35, 0.26 to 0.46), with only a third achieving seroconversion. Seroconversion was increasingly likely in patients with haematological cancers (0.63, 0.57 to 0.69, I²=88%; 0.62, 0.54 to 0.70, I²=90%), immune mediated inflammatory disorders (0.75, 0.69 to 0.82, I²=92%; 0.77, 0.66 to 0.85, I²=93%), and solid cancers (0.90, 0.88 to 0.93, I²=51%; 0.89, 0.86 to 0.91, I²=49%). Seroconversion was similar between people with HIV and immunocompetent controls (1.00, 0.98 to 1.01, I²=0%; 0.97, 0.83 to 1.00, I²=89%). Systematic review of 11 studies showed that a third dose of a covid-19 mRNA vaccine was associated with seroconversion among vaccine non-responders with solid cancers, haematological cancers, and immune mediated inflammatory disorders, although response was variable in transplant recipients and inadequately studied in people with HIV and those receiving non-mRNA vaccines.

CONCLUSION

Seroconversion rates after covid-19 vaccination were significantly lower in immunocompromised patients, especially organ transplant recipients. A second dose was associated with consistently improved seroconversion across all patient groups, albeit at a lower magnitude for organ transplant recipients. Targeted interventions for immunocompromised patients, including a third (booster) dose, should be performed.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42021272088.

Fighting the SARS-CoV-2 pandemic requires a global approach to understanding the heterogeneity of vaccine responses

Host genetic and environmental factors including age, biological sex, diet, geographical location, microbiome composition and metabolites converge to influence innate and adaptive immune responses to vaccines. Failure to understand and account for these factors when investigating severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine efficacy may impair the development of the next generation of vaccines. Most studies aimed at identifying mechanisms of vaccine-mediated immune protection have focused on adaptive immune responses. It is well established, however, that mobilization of the innate immune response is essential to the development of effective cellular and humoral immunity. A comprehensive understanding of the innate immune response and environmental factors that contribute to the development of broad and durable cellular and humoral immune responses to SARS-CoV-2 and other vaccines requires a holistic and unbiased approach. Along with optimization of the immunogen and vectors, the development of adjuvants based on our evolving understanding of how the innate immune system shapes vaccine responses will be essential. Defining the innate immune mechanisms underlying the establishment of long-lived plasma cells and memory T cells could lead to a universal vaccine for coronaviruses, a key biomedical priority.

Recent advances in nanotechnology-based COVID-19 vaccines and therapeutic antibodies

COVID-19 has caused a global pandemic and millions of deaths. It is imperative to develop effective countermeasures against the causative viral agent, SARS-CoV-2 and its many variants. Vaccines and therapeutic antibodies are the most effective approaches for preventing and treating COVID-19, respectively. SARS-CoV-2 enters host cells through the activities of the virus-surface spike (S) protein. Accordingly, the S protein is a prime target for vaccines and therapeutic antibodies. Dealing with particles with dimensions on the scale of nanometers, nanotechnology has emerged as a critical tool for rapidly designing and developing safe, effective, and urgently needed vaccines and therapeutics to control the COVID-19 pandemic. For example, nanotechnology was key to the fast-track approval of two mRNA vaccines for their wide use in human populations. In this review article, we first explore the roles of nanotechnology in battling COVID-19, including protein nanoparticles (for presentation of protein vaccines), lipid nanoparticles (for formulation with mRNAs), and nanobodies (as unique therapeutic antibodies). We then summarize the currently available COVID-19 vaccines and therapeutics based on nanotechnology.

Predictive Factors for Neutralizing Antibody Levels Nine Months after Full Vaccination with BNT162b2: Results of a Machine Learning Analysis

Vaccination against SARS-CoV-2 with BNT162b2 mRNA vaccine plays a critical role in COVID-19 prevention. Although BNT162b2 is highly effective against COVID-19, a time-dependent decrease in neutralizing antibodies (NAbs) is observed. The aim of this study was to identify the individual features that may predict NAbs levels after vaccination. Machine learning techniques were applied to data from 302 subjects. Principal component analysis (PCA), factor analysis of mixed data (FAMD), k-means clustering, and random forest were used. PCA and FAMD showed that younger subjects had higher levels of neutralizing antibodies than older subjects. The effect of age is strongest near the vaccination date and appears to decrease with time. Obesity was associated with lower antibody response. Gender had no effect on NAbs at nine months, but there was a modest association at earlier time points. Participants with autoimmune disease had lower inhibitory levels than participants without autoimmune disease. K-Means clustering showed the natural grouping of subjects into five categories in which the characteristics of some individuals predominated. Random forest allowed the characteristics to be ordered by importance. Older age, higher body mass index, and the presence of autoimmune diseases had negative effects on the development of NAbs against SARS-CoV-2, nine months after full vaccination.

Sustained but Declining Humoral Immunity Against SARS-CoV-2 at 9 Months Postvaccination With BNT162b2: A Prospective Evaluation in 309 Healthy Individuals

The sustainability of coronavirus 19 (COVID-19) vaccine-induced immunity against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is critical to be determined to inform public health decisions on vaccination programs and prevention measures against COVID-19. The aim of the present study was to prospectively evaluate the kinetics of neutralizing antibodies (NAbs) and anti-S-receptor binding domain (RBD IgGs) against SARS-CoV-2 after full vaccination with the BNT162b2 mRNA vaccine for up to 9 months in healthy individuals (NCT04743388). The assessments were performed at the following time points after the second vaccination: 2 weeks, 1 month, 3 months, 6 months, and 9 months. The measurements were performed with the GenScript's cPassTM SARS-CoV-2 NAbs Detection Kit (GenScript, Inc.; Piscataway, NJ) and the Elecsys Anti-SARS-CoV-2 S assay (Roche Diagnostics GmbH; Mannheim, Germany). Three hundred nine participants with a median age of 48 years were included. A gradual decline in both NAbs and anti-S-RBD IgGs became evident from 2 weeks to 9 months postvaccination. Both NAbs and anti-S-RBD IgGs levels were significantly lower at 9 months compared with the previous timepoints. Interestingly, age was found to exert a statistically significant effect on NAbs elimination only during the first-trimester postvaccination, as older age was associated with a more rapid clearance of NAbs. Furthermore, simulation studies predicted that the median NAb value would fall from 66% at 9 months to 59% and 45% at 12 and 18 months postvaccination, respectively. This finding may reflect a declining degree of immune protection against COVID-19 and advocates for the administration of booster vaccine shots especially in areas with emerging outbreaks.