Neutralizing antibodies to Omicron after the fourth SARS-CoV-2 mRNA vaccine dose in immunocompromised patients highlight the need of additional boosters

Immunocompromised patients have been shown to have an impaired immune response to COVID-19 vaccines. Here we compared the B-cell, T-cell and neutralizing antibody response to WT and Omicron BA.2 SARS-CoV-2 virus after the fourth dose of mRNA COVID-19 vaccines in patients with hematological malignancies (HM, n=71), solid tumors (ST, n=39) and immune-rheumatological (ID, n=25) diseases. We show that the T-cell response is similarly boosted by the fourth dose across the different subgroups, while the antibody response is improved only in patients not receiving B-cell targeted therapies, independent on the pathology. However, 9% of patients with anti-RBD antibodies did not have neutralizing antibodies to both virus variants, while an additional 5.7% did not have neutralizing antibodies to Omicron BA.2, making these patients particularly vulnerable to SARS-CoV-2 infection. The increment of neutralizing antibodies was very similar towards Omicron BA.2 and WT virus after the third or fourth dose of vaccine, suggesting that there is no preferential skewing towards either virus variant with the booster dose. The only limited step is the amount of antibodies that are elicited after vaccination, thus increasing the probability of developing neutralizing antibodies to both variants of virus. Hence, additional booster doses are recommended to frail patients.

mRNA-COVID19 vaccination can be considered safe and tolerable for frail patients

BackgroundFrail patients are considered at relevant risk of complications due to COVID-19 infection and, for this reason, are prioritized candidates for vaccination. As these patients were originally not included in the registration trials, fear related to vaccine side-effects and disease worsening was one of the reasons for vaccine hesitancy. Herein we report the safety profile of the prospective, multicenter, national VAX4FRAIL study (NCT04848493) to evaluate vaccines in a large trans-disease cohort of patients with solid or hematological malignancies, neurological and rheumatological diseases. MethodsBetween March 3rd and September 2nd, 2021, 566 patients were evaluable for safety endpoint: 105 received the mRNA-1273 vaccine and 461 the BNT162b2 vaccine. Frail patients were defined per protocol as patients under treatment with hematological malignancies (131), solid tumors (191), immune-rheumatological diseases (86), and neurological diseases (158), including multiple sclerosis and generalized myasthenia. The impact of the vaccination on the health status of patients was assessed through a questionnaire focused on the first week after each vaccine dose. ResultsThe most frequently reported moderate-severe adverse events were pain at the injection site (60.3% after the first dose, 55.4% after the second), fatigue (30.1% - 41.7%), bone pain (27.4% - 27.2%) and headache (11.8% - 18.9%). Risk factors associated with the occurrence of severe symptoms after vaccine administration were identified through a multivariate logistic regression analysis: age was associated with severe fever presentation (younger patients vs. middle-aged vs. older ones), females presented a higher probability of severe pain at the injection site, fatigue, headache, and bone pain; the mRNA-1237 vaccine was associated with a higher probability of severe pain at the injection site and fever. After the first dose, patients presenting a severe symptom were at a relevant risk of recurrence of the same severe symptom after the second one. Overall, 11 patients (1.9%) after the first dose and 7 (1.2%) after the second one required to postpone or suspend the disease-specific treatment. Finally, 2 fatal events occurred among our 566 patients. These two events were considered unrelated to the vaccine. ConclusionsOur study reports that mRNA-COVID-19 vaccination is safe also in frail patients as expected side effects were manageable and had a minimum impact on patient care path. ImportanceOur study reports the safety analysis of the trial VAX4FRAIL confirming that mRNA-COVID-19 vaccination is safe in frail immunocompromised patients: expected side effects were manageable and had a minimum impact on patient care path. ObjectiveTo evaluate the safety of mRNA-COVID-19 vaccination in vulnerable patients. DesignVAX4FRAIL is a national, multicentric, observational, prospective trial (start date March 3rd, 2021 - primary completion date September 2nd, 2021). SettingMulticenter prospective trial. ParticipantsFrail patients were defined per protocol as patients under treatment with solid tumors (191), immune-rheumatological diseases (86), hematological malignancies (131), and neurological diseases (158), including multiple sclerosis and generalized myasthenia. ExposureOverall, 105 received the mRNA-1273 vaccine and 461 the BNT162b2 vaccine. Main OutcomeThe occurrence of adverse events after 1st and 2nd m-RNA-COVID-19 vaccination was analyzed. Adverse events were collected through a questionnaire comprising both open and closed questions. ResultsThe most frequently reported moderate-severe adverse events were pain at the injection site (60.3% after the first dose, 55.4% after the second), fatigue (30.1% - 41.7%), bone pain (27.4% - 27.2%) and headache (11.8% - 18.9%). Risk factors associated with the occurrence of severe symptoms after vaccine administration were identified through a multivariate logistic regression analysis: age was associated with severe fever presentation (younger patients vs. middle-aged vs. older ones), females presented a higher probability of severe pain at the injection site, fatigue, headache, and bone pain; the mRNA-1237 vaccine was associated with a higher probability of severe pain at the injection site and fever. Patients presenting a severe symptom after the first dose were at a relevant risk of recurrence of the same severe symptom after the second one. Overall, 11 patients (1.9%) after the first dose and 7 (1.2%) after the second one was required to postpone or suspend their disease-specific treatment. Finally, 2 fatal events occurred among our 566 patients, and these two events were due to disease progression and considered unrelated to the vaccine. Conclusion and RelevanceOur study reports that mRNA-COVID-19 vaccination is safe also in frail patients as expected side effects were manageable and had a minimum impact on patient care path. Study RegistrationA National, Multicentric, Observational, Prospective Study to Assess Immune Response to COVID-19 Vaccine in Frail Patients (VAX4FRAIL). NCT04848493 https://clinicaltrials.gov/ct2/show/NCT04848493 Key PointsO_ST_ABSQuestionC_ST_ABSCan m-RNA-COVID19 vaccination be considered safe for frail patients? FindingsIn this national, multicentric, observational, prospective trial (NCT04848493) that included 566 frail patients, the occurrence of both local and systemic adverse events was manageable and did not negatively impact on the general treatment program. MeaningmRNA-COVID19 vaccination is safe among frail immunocompromised patients.

Humoral and T-cell immune response after three doses of mRNA SARS-CoV-2 vaccines in fragile patients: the Italian VAX4FRAIL study

BackgroundPatients with solid or hematological tumors, neurological and immune-inflammatory disorders represent potentially fragile subjects with increased risk to experience severe COVID-19 and inadequate response to SARS-CoV2 vaccination. MethodsWe designed a prospective Italian multicentric study to assess humoral and T-cell response to SARS-CoV2 vaccination in patients (n=378) with solid tumors (ST), hematological malignancies (HM), neurological (ND) and immuno-rheumatological diseases (ID). The immunogenicity of primary vaccination schedule and of the booster dose were analyzed. ResultsOverall, patient seroconversion rate after two doses was 62.1%. A significant lower rate was observed in HM (52.4%) and ID (51.9%) patients compared to ST (95.6%) and ND (70.7%); a lower median level of antibodies was detected in HM and ID versus the others (p<0.0001). A similar rate of patients with a positive SARS-CoV2 T-cell response was observed in all disease groups, with a higher level observed in the ND group. The booster dose improved humoral responses in all disease groups, although with a lower response in HM patients, while the T-cell response increased similarly in all groups. In the multivariable logistic model, the independent predictors for seroconversion were disease subgroups, type of therapies and age. Notably, the ongoing treatment known to affect the immune system was associated with the worst humoral response to vaccination (p<0.0001), but had no effects on the T-cell responses. ConclusionsImmunosuppressive treatment more than disease type per se is a risk factor for low humoral response after vaccination. The booster dose can improve both humoral and T-cell response. Articles main point- Lower rate of seroconversion was observed in fragile patients as compared to healthy controls - The booster dose improves humoral and T-cell response in all fragile patient groups - Immunosuppressive treatment was associated with the worst humoral response to vaccination, but had no effects on T-cell responses.

COVID-eVax, an electroporated plasmid DNA vaccine candidate encoding the SARS-CoV-2 Receptor Binding Domain, elicits protective immune responses in animal models of COVID-19

The COVID-19 pandemic caused by the {beta}-coronavirus SARS-CoV-2 has made the development of safe and effective vaccines a critical global priority. To date, four vaccines have already been approved by European and American authorities for preventing COVID-19 but the development of additional vaccine platforms with improved supply and logistics profiles remains a pressing need. Here we report the preclinical evaluation of a novel COVID-19 vaccine candidate based on the electroporation of engineered, synthetic cDNA encoding a viral antigen in the skeletal muscle, a technology previously utilized for cancer vaccines. We constructed a set of prototype DNA vaccines expressing various forms of the SARS-CoV-2 Spike (S) protein and assessed their immunogenicity in animal models. Among them, COVID-eVax - a DNA plasmid encoding a secreted monomeric form of SARS-CoV-2 S protein RBD - induced the most potent anti-SARS-CoV-2 neutralizing antibody responses (including against the current most common variants of concern) and a robust T cell response. Upon challenge with SARS-CoV-2, immunized K18-hACE2 transgenic mice showed reduced weight loss, improved pulmonary function and significantly lower viral replication in the lungs and brain. COVID-eVax conferred significant protection to ferrets upon SARS-CoV-2 challenge. In summary, this study identifies COVID-eVax as an ideal COVID-19 vaccine candidate suitable for clinical development. Accordingly, a combined phase I-II trial has recently started in Italy.

Obesity may hamper SARS-CoV-2 vaccine immunogenicity

BackgroundThe first goal of the study was to analyse the antibody titre 7 days after the second dose of BNT162b2 vaccine in a group of 248 healthcare workers (HCW). The second goal was to analyse how the antibody titre changes in correlation with age, gender and BMI. MethodsParticipants were assigned to receive the priming dose at baseline and booster dose at day 21. Blood and nasopharyngeal swabs were collected at baseline and 7 days after second dose of vaccine. Findings248 HWCs were analysed, 158 women (63.7%) and 90 men (36.3%). After the second dose of BNT162b2 vaccine, 99.5% of participants developed a humoral immune response. The geometric mean concentration of antibodies among the vaccinated subjects after booster dose (285.9 AU/mL 95% CI: 249.5-327.7); was higher than that of human convalescent sera (39.4 AU/mL, 95% CI: 33.1-46.9), with p<0.0001. The antibody titre was found to be higher in young and female participants. A strong correlation of BMI classes with antibody titres was noticed: humoral response was more efficient in the group with under- and normal-weight vs the group with pre- and obesity participants (p<0.0001 at T1). InterpretationThese findings imply that females, lean and young people have an increased capacity to mount humoral immune responses compared to males, overweight and the older population. Although further studies are needed, this data may have important implications for the development of vaccination strategies for COVID-19, particularly in obese people. FundingNone

Companion vaccine Bioinformatic design tool reveals limited functional genomic variability of SARS-Cov-2 Spike Receptor Binding Domain

BackgroundTracking the genetic variability of Severe Acute Respiratory Syndrome CoronaVirus 2 (SARS-CoV-2) is a crucial challenge. Mainly to identify target sequences in order to generate robust vaccines and neutralizing monoclonal antibodies, but also to track viral genetic temporal and geographic evolution and to mine for variants associated with reduced or increased disease severity. Several online tools and bioinformatic phylogenetic analyses have been released, but the main interest lies in the Spike protein, which is the pivotal element of current vaccine design, and in the Receptor Binding Domain, that accounts for most of the neutralizing the antibody activity. MethodsHere, we present an open-source bioinformatic protocol, and a web portal focused on SARS-CoV-2 single mutations and minimal consensus sequence building as a companion vaccine design tool. Furthermore, we provide immunogenomic analyses to understand the impact of the most frequent RBD variations. ResultsResults on the whole GISAID sequence dataset at the time of the writing (October 2020) reveals an emerging mutation, S477N, located on the central part of the Spike protein Receptor Binding Domain, the Receptor Binding Motif. Immunogenomic analyses revealed some variation in mutated epitope MHC compatibility, T-cell recognition, and B-cell epitope probability for most frequent human HLAs. ConclusionsThis work provides a framework able to track down SARS-CoV-2 genomic variability.

TMPRSS2, a SARS-CoV-2 internalization protease is downregulated in head and neck cancer patients.

ObjectivesTwo of the main target tissues of SARS-coronavirus 2 are the oral cavity pharynx-larynx epithelium, the main virus entry site, and the lung epithelium. The virus enters host cells through binding of the Spike protein to ACE2 receptor and subsequent S priming by the TMPRSS2 protease. Herein we aim to assess differences in both ACE2 and TMPRSS2 expression in normal tissues from oral cavity-pharynx-larynx and lung tissues as well as neoplastic tissues from the same histological areas. The information provided in this study may contribute to better understanding of SARS-coronavirus 2 ability to interact with different biological systems and contributes to cumulative knowledge on potential mechanisms to inhibit its diffusion. Materials and MethodsThe study has been conducted using The Cancer Genome Atlas (TCGA) and the Regina Elena Institute (IRE) databases and validated by experimental model in HNSCC and Lung cancer cells. Data from one COVID19 positive patient who was operated on for HNSCC was also included. We have analyzed 478 tumor samples and 44 normal samples from TCGA HNSCC cohort for whom both miRNA and mRNA sequencing was available. The dataset included 391 HPV- and 85 HPV+ cases, with 331 P53 mutated and 147 P53 wild type cases respectively. 352 out of 478 samples were male and 126 female. In IRE cohort we analyzed 66 tumor samples with matched normal sample for miRNA profiling and 23 tumor\normal matched samples for mRNA profiling. 45 out of 66 tumors from IRE cohort were male and 21 female, 38 were P53 mutated and 27 wild type. Most patients (63 of 66) in IRE cohort were HPV negative. Normalized TCGA HNSCC gene expression and miRNA expression data were obtained from Broad Institute TCGA Genome Data Analysis Center (http://gdac.broadinstitute.org/). mRNA expression data from IRE cohort used in this study has been deposited to NCBIs Gene Expression Omnibus and is accessible through GEO series accession number GSE107591. In order to inference about potential molecular modulation of TMPRSS2, we also included miRNAs expression for the 66 IRE cohort matched tumor and normal samples from Agilent platform. DNA methylation data for TCGA tumors were obtained from Wanderer (http://maplab.imppc.org/wanderer/). We used miRWalk and miRNet web tools for miRNA-target interaction prediction and pathway enrichment analysis. The correlation and regression analyses as well as the miRNA and gene modulation and the survival analysis were conducted using Matlab R2019. ResultsTMPRSS2 expression in HNSCC was significantly reduced compared to the normal tissues and had a prognostic value in HNSCC patients. Reduction of TMPRSS2 expression was more evident in women than in men, in TP53 mutated versus wild TP53 tumors as well as in HPV negative patients compared to HPV positive counterparts. Functionally, we assessed the multivariate effect on TMPRSS2 in a single regression model. We observed that all variables had an independent effect on TMPRSS2 in HNSCC patients with HPV negative, TP53 mutated status and with elevated TP53-dependent Myc-target genes associated with low TMPRSS2 expression. Investigation of the molecular modulation of TMPRSS2 in both HNSCC and lung cancers revealed that expression of microRNAs targeting TMPRSS2 anti-correlated in both TCGA and IRE HNSCC datasets, while there was not evidence of TMPRSS2 promoter methylation in both tumor cohorts. Interestingly, the anti-correlation between microRNAs and TMPRSS2 expression was corroborated by testing this association in a SARS-CoV-2 positive HNSCC patient. ConclusionsCollectively, these findings suggest that tumoral tissues, herein exemplified by HNSCC and lung cancers might be more resistant to SARS-CoV-2 infection due to reduced expression of TMPRSS2. The protective mechanism might occur, at least partially, through the aberrant activation of TMPRSS2 targeting microRNAs; thereby providing strong evidence on the role of non-coding RNA molecule in host viral infection. These observations may help to better assess the frailty of SARS-CoV-2 positive cancer patients.