Jcovden (COVID-19 vaccine (Ad26.COV2-S [recombinant])) / J&J - LARVOL DELTA

Functional analyses of vitt patient-derived PF4-antibodies and adenoviral vaccine compounds reveal unique patient-specific profiles of multicellular activation (ASH 2025) - "Vaccine-induced thrombotic thrombocytopenia (VITT) is a rare but life-threatening adverse reaction toCOVID-19 vaccines resulting in thrombosis and thrombocytopenia; particularly due to adenoviral vector-based vaccines (ChAdOx1 nCoV-19, Ad26.COV2.S). We will also test this in conjunction with VITT antibodies.Taken together, we have constructed a blueprint of VITT anti-PF4-induced multicellular activation whichreveals unique VITT patient-specific features, as demonstrated using 8 VITT-antibodies derived from 4different patients. This advances our understanding of VITT antibody heterogeneity from a functionalperspective, which may be exploited for novel diagnostic and therapeutic strategies."

Clinical • Cardiovascular • Hematological Disorders • Infectious Disease • Novel Coronavirus Disease • Thrombocytopenia • Thrombosis • ANXA5 • CDH5 • CEACAM8 • ITGAM • SELP

Association between sars-cov-2 infection, COVID-19 vaccines and immune thrombocytopenia in adults. a nationwide population-based study in France. (ASH 2025) - P=N/A | "Although such cases were expected to be sporadic, the possibility of an increased risk at thepopulation level remained uncertain to date.Therefore, we aimed to measure the association between COVID-19 vaccines overall and by type (mRNAvaccines: Comirnaty Pfizer - BNT162b2; Spikevax Moderna - mRNA-12773; and adenovirus-basedvaccines: Vaxzevria AstraZeneca -ChadOx-1-S, and JCovden Janssen AD26COV-2.S) and the occurrence ofITP at the nationwide scale in France. This nationwide population-based study using three different designs showed an associationbetween SARS-CoV-2 infection and ChadOx1-S vaccine with ITP occurrence, while no association wasfound for mRNA vaccines."

Clinical • Hematological Disorders • Immune Thrombocytopenic Purpura • Infectious Disease • Novel Coronavirus Disease • Respiratory Diseases • Thrombocytopenia • Thrombocytopenic Purpura

Real-world effectiveness of Ad26.COV2.S or BNT162b2 booster vaccines against severe COVID-19 in adults who received a primary dose of Ad26.COV2.S in South Africa during the Delta period: A retrospective cohort study using medical scheme data. (PubMed, S Afr Med J) - "While most participants remained unboosted, administration of either ancestral strain Ad26.COV2.S or BNT162b2 vaccination provided protection against severe COVID-19 outcomes among essential workers in SA during the dominance of the Omicron BA.1 and BA.4/5 variants, demonstrating cross-strain protection."

Journal • Real-world evidence • Retrospective data • Critical care • Infectious Disease • Novel Coronavirus Disease • Respiratory Diseases

Clot twist - D-dimer analysis of healthy adults receiving heterologous or homologous booster COVID-19 vaccine after a single prime dose of Ad26.COV2.S in a phase II randomised open-label trial, BaSiS. (PubMed, S Afr Med J) - "Elevated D-dimer levels in asymptomatic, low-risk adults were unexpectedly common and not associated with thromboembolism. This supports the rationale of including D-dimer testing in conjunction with other coagulopathy markers, only if clinically indicated in both COVID-19 vaccine clinical trials and the general population."

Clinical • Journal • P2 data • Cardiovascular • Hematological Disorders • Human Immunodeficiency Virus • Infectious Disease • Novel Coronavirus Disease • Obesity • Thrombocytopenia

Platelet Factor 4 Antibody Persistence and Long-term Pathogenicity in Vaccine-induced Immune Thrombotic Thrombocytopenia. (PubMed, medRxiv) - "To study this, acute and follow-up samples were obtained from six Ad26.COV2.S-associated VITT patients, with a median time to follow-up of 244 days from acute presentation (Range, 114-664 days). While none of these six antibodies caused long-term thrombocytopenia or thrombosis, platelet-activating anti-PF4 antibodies were seen four years after the acute event in an additional ChAdOx1 nCoV-19-associated VITT patient. These antibodies continued to cause chronic low-grade thrombocytopenia, highlighting the potential for long-term sequelae in what is generally viewed as a transient thrombotic thrombocytopenic syndrome."

Journal • Cardiovascular • Hematological Disorders • Monoclonal Gammopathy • Thrombocytopenia • Thrombosis

Heterologous ORFV-Ad26 vaccination broadens antibody breadth and amplifies cellular immunity against SARS-CoV-2 spike. (PubMed, Front Immunol) - "Here, we evaluated a replication-deficient Orf virus-based spike vaccine (ORFV-S) in combination with the licensed Ad26 vector vaccine Jcovden (Ad26.COV2.S), using SARS-CoV-2 model...In the reverse regimen, ORFV-S boost improved inhibition across multiple SARS-CoV-2 variants, including immune-evasive strains and indicated qualitative improvements in the response breadth. Together, these findings suggest that sequence-dependent effects allow heterologous schedules to emphasize either cellular or humoral arms of the adaptive response."

Journal • Infectious Disease • Novel Coronavirus Disease • Respiratory Diseases • CD4 • CD8

Immune responses after two inactivated COVID-19 vaccine doses, a heterologous third dose and subsequent boosting with bivalent mRNA in adults. (PubMed, Sci Rep) - "Healthy participants (age > 18) who completed two doses of inactivated COVID-19 vaccine and received any of these booster vaccines (Ad26.COV2.S, ChAdOx1, or mRNA-based) at least 12 months prior were enrolled...Bivalent mRNA ancestral/BA.4/5 vaccine enhanced humoral immunity against both ancestral and Omicron XBB1.5, and T-cell immunity in inactivated COVID-19 vaccine primed with different heterologous boost participants. The study was registered at WHO platform: Thai Clinical Trial Registry (TCTR20230811004)."

Journal • Infectious Disease • Novel Coronavirus Disease • IFNG

Prospective SARS-CoV-2 additional vaccination in immunosuppressant-treated individuals with autoimmune diseases in a randomized controlled trial. (PubMed, JCI Insight) - P2 | "Additional COVID-19 vaccination is effective and safe in individuals with ADs treated with immunosuppressants, regardless of whether MMF/MPA or MTX is withheld."

Journal • Immunology • Infectious Disease • Novel Coronavirus Disease • Respiratory Diseases • Rheumatology

Strong immunogenicity and protection against SARS-CoV-2 in hamsters induced by heterologous boost vaccination with an MVA-based COVID-19 vaccine candidate. (PubMed, J Gen Virol) - "Hamsters were primed with an mRNA vaccine (BNT162b2, BioNTech/Pfizer) or the adenoviral vector vaccine Ad26.COV2.S (Janssen) and subsequently boosted with MVA-ST at a dose of 10⁸ p.f.u. Notably, even a lower booster dose (10⁷ p.f.u.) of MVA-ST following mRNA priming conferred strong protection against SARS-CoV-2 challenge infection, while still associated with limited viral shedding from the upper respiratory tract. These findings highlight the potential of MVA-ST as a heterologous booster to enhance the immunogenicity and protective efficacy of existing COVID-19 vaccines and also to improve vaccination strategies against other emerging pathogens."

Journal • Preclinical • Infectious Disease • Novel Coronavirus Disease • Respiratory Diseases

Long-term trends in reporting of cardiac adverse drug reactions to COVID-19 vaccines - an exploratory analysis of the EudraVigilance database. (PubMed, BMC Infect Dis) - "The frequency of reporting suspected SCADRs after COVID-19 vaccinations appears to change dynamically over time. Concerning the administration of vaccine doses, the reporting of potential post-vaccination ADRs seems to be more distributed in time. These observations suggest that post-approval long-term monitoring of suspected ADRs may be valuable for improving data capture and supporting vaccine safety assessment. This underlines the potential importance of comprehensive surveillance in the context of infectious diseases and vaccine development programs."

Adverse drug reaction • Journal • Cardiovascular • Hematological Disorders • Infectious Disease • Inflammation • Novel Coronavirus Disease • Thrombosis

Incidence and Management of COVID-19 Infections in Vaccinated Patients with CLL (ASH 2023) - P | "The incidence of COVID-19 was comparable amongst men and women in the initial cohort (4%, 2%) and booster cohort (25%, 24%) as well as those who received mRNA-1273 and BNT162b2 vaccines (2%, 4%) and (24%, 26%). There were no infections in the 6 pts who received Ad26.COV2.S in the initial cohort nor 4 in booster cohort. Infections by treatment in initial cohort: 1% of treatment-native, 4% BTKi, 7% CD20 mAb + venetoclax, 9% BTKi + venetoclax...All infections (8/8) occurred in the initial cohort prior to the receipt of tixagevimab/cilgavimab or in those who did not receive prophylaxis; 84% (27/32) in the booster cohort... There were 243 pts enrolled in the initial vaccine cohort from 03/21-09/21 and 129 in the booster cohort from 08/21-02/22; 73 pts from initial cohort enrolled into the booster cohort. Patient characteristics are in Table 1. Eight pts (3.3%) reported COVID-19 in the initial cohort within 1 year of receiving the initial vaccine or prior to receipt of a..."

Clinical • Chronic Lymphocytic Leukemia • Infectious Disease • Novel Coronavirus Disease • Respiratory Diseases • CD20

COVID-19 Vaccine-Induced Cardiac Inflammation: A Review of 103 Cases and Appraisal of VAERS Database (AHA 2025) - "The BNT162b2 (Pfizer) vaccine was associated with the highest number of cases (n=67), followed by mRNA1273 (Moderna, n=29), and Ad26.COV2.S (J&J, n=4). Clinical outcomes were favorable in 93.1% of cases, with symptom resolution and discharge. Five deaths were reported."

Clinical • Review • Cardiovascular • Infectious Disease • Inflammation • Novel Coronavirus Disease • Respiratory Diseases

COVID-19 Vaccine-Induced Minimal Change Disease Nephropathy: A Rare Complication (KIDNEY WEEK 2025) - "PCP started a low dose of steroids 20 mg and proteinuria started to decrease to 748, 397, and 280 grams respectively, after that patient began tapering down prednisone...Although this adverse event is uncommon, considering the limited published data and the absence of confirmed causality. Increased awareness is essential for early diagnosis and optimal treatment of affected patients."

Breast Cancer • Glomerulonephritis • Hypotension • Infectious Disease • Nephrology • Novel Coronavirus Disease • Renal Disease • Respiratory Diseases • Rheumatology

Clonal Persistence of Anti-PF4 Antibodies in VITT Represents an MGTS-like State (ASH 2024) - "Results : Follow-up samples were obtained from 6 VITT patients after Ad26.COV2.S vaccination...This patient, who experienced severe thrombosis after ChAdOx1 nCoV19 vaccination, demonstrated persistent ELISA and PEA positivity even three years after symptom onset but had not experienced breakthrough thrombosis while on anticoagulation therapy...This study also demonstrates the first example of a VITT antibody with a kappa light chain. The requirement for anticoagulation in patients demonstrating ELISA-positive/functional test-negative results is not clear, but the persistence of mono/oligoclonal anti-PF4 antibodies raises the possibility for the upregulation of pathogenic antibody production in proinflammatory settings."

Cardiovascular • Hematological Disorders • Monoclonal Gammopathy • Thrombocytopenia • Thrombosis

Immune correlates analysis of antibody responses against SARS-CoV-2 variants in the ENSEMBLE vaccine efficacy trial. (PubMed, iScience) - "In Latin American sites of the ENSEMBLE trial of the Ad26.COV2.S vaccine vs. placebo, binding antibodies and neutralizing antibodies measured 4 weeks post-vaccination (∼peak) against circulating lineages (Ancestral, Gamma, Lambda, Mu, Zeta) were assessed as a correlate of risk of, and correlate of protection against, lineage-specific COVID-19...Lambda departed from this model at undetectable/just-detectable titers: at ∼ peak Reference-specific titers of 2.7 arbitrary units (AU)/mL (just-detectable) and 30 AU/ml, VE against Ancestral COVID-19 was 53.0% (95% CI: 30.7%, 67.9%) and 84.5% (73.6%, 93.0%), respectively; at the same Lambda-specific titers, VE against Lambda COVID-19 was 12.3% (-54.1%, 50.3%) and 91.1% (68.9%, 98.0%). Additional research is needed for Omicron variants."

Journal • Infectious Disease • Novel Coronavirus Disease • Respiratory Diseases

Perspectives on the impact of regulatory measures on national COVID-19 vaccination programs: a qualitative study from six EU member states. (PubMed, J Pharm Policy Pract) - "The European Medicines Agency (EMA) issued regulatory recommendations and communications in 2021 about the risk of thrombosis with thrombocytopenia syndrome (TTS) associated with COVID-19 adenoviral vector vaccines Vaxzevria and Jcovden...National decision-makers country reverted to their preferred sources. The use of varying sources explains some of the variations in the vaccination strategies."

Journal • Cardiovascular • Hematological Disorders • Infectious Disease • Novel Coronavirus Disease • Thrombocytopenia • Thrombosis

Free Nucleic acids in ChAdOx1 nCoV-19 adenovirus vector vaccine contribute to an anti-platelet factor 4 antibody response. (PubMed, Thromb Haemost) - "Virion-unbound DNA in ChAdOx1 nCoV-19 contributes to anti-PF4 antibody formation. This highlights the potential of reducing virion-unbound DNA in vaccine formulations to mitigate unintended immune responses to PF4."

Journal • Cardiovascular • Hematological Disorders • Immune Thrombocytopenic Purpura • Infectious Disease • Novel Coronavirus Disease • Respiratory Diseases • Thrombocytopenia • Thrombocytopenic Purpura • Thrombosis

Electronic health record analysis reveals no association between COVID-19 vaccines and ischemic stroke. (PubMed, J Neurol Sci) - "Results indicate no association between mRNA or adenovirus COVID-19 vaccines and ischemic stroke."

Journal • Cardiovascular • Infectious Disease • Ischemic stroke • Novel Coronavirus Disease • Respiratory Diseases

Enhanced adenoviral reactivity in Guillain-Barré syndrome after SARS-CoV-2 infection and vaccination. (PubMed, Brain) - "Sera from GBS patients and from individuals who received COVID-19 vaccinations (n=36: 16 ChAdOx1, 10 Ad26.COV2.S/Janssen, and 10 Tozinameran/Pfizer-BioNTech) without developing GBS were tested for IgG reactivity against SARS-CoV-2 and adenoviral proteins. However, we found no mechanistic link between S1 and peripheral nerve reactivity or pathology. Serological responses to adenoviral proteins may be directly involved in the pathogenesis of Guillain-Barré syndrome, potentially contributing to cases with currently unexplained aetiology."

Journal • Infectious Disease • Novel Coronavirus Disease • Pain • Respiratory Diseases

Longitudinal evaluation of T-cell responses to Pfizer-BioNTech and Janssen SARS-CoV-2 vaccines as boosters in Ghanaian adults. (PubMed, Front Immunol) - "In addition, T-cell inhibitory molecule kinetics suggests an efficient T-cell activity. These findings may have implications for the overall induction of long-term protective immunity by the two vaccine types."

IO biomarker • Journal • Infectious Disease • Novel Coronavirus Disease • Respiratory Diseases • CD4 • CD8 • HAVCR2 • IFNG • IL12A • IL17A • IL1B • IL2 • IL6 • PD-1 • TNFA

No disproportionate reporting of inflammatory arthritis following COVID-19 vaccination: a pharmacovigilance study using VAERS data. (PubMed, Semin Arthritis Rheum) - "Our findings demonstrate that there is no disproportionate reporting of inflammatory arthritis following COVID-19 vaccination compared to other vaccines, supporting the overall safety of COVID-19 vaccines."

Adverse events • Journal • Herpes Zoster • Immunology • Infectious Disease • Inflammatory Arthritis • Influenza • Novel Coronavirus Disease • Respiratory Diseases • Rheumatology • Varicella Zoster

Janssen Ad26.CoV2.S Vaccine Booster in Kidney Transplant Recipients (clinicaltrials.gov) - P3 | N=468 | Terminated | Sponsor: Mark Stegall | Completed ➔ Terminated; Janssen Biotech, Inc stopped production of the vaccine, and it was no longer available as of 2023.

Trial termination • Infectious Disease • Novel Coronavirus Disease • Respiratory Diseases • Transplantation

Dose-dependent interferon programs in myeloid cells after mRNA and adenovirus COVID-19 vaccination. (PubMed, bioRxiv) - "We longitudinally profiled SARS-CoV-2-naïve adults (n=31) vaccinated with BNT162b2, mRNA-1273, or Ad26.COV2.S, integrating plasma cytokines, antibody titers, and single-cell multi-omic data (DOGMA-seq). In vitro stimulation of human monocytes showed that IFN-α alone recapitulates ISG-dim, whereas both IFN-α and IFN-γ are required for ISG-high. These findings define dose-dependent interferon programming in human myeloid cells, highlight mechanistic differences between priming and boosting, with implications for optimizing vaccine platform choice, dose scheduling, and formulation."

Journal • Infectious Disease • Novel Coronavirus Disease • Respiratory Diseases • DDX58 • IFNA1 • IFNG • MX1

Safety, immunogenicity and pregnancy outcomes in mothers and infants after vaccination with an adenovirus-vector COVID-19 vaccine during pregnancy. (PubMed, Hum Vaccin Immunother) - P2 | "We assessed the safety, reactogenicity, and immunogenicity of maternal vaccination with Ad26.COV2.S COVID-19 vaccine and monitored serum and breast milk antibody levels in mothers and infants until 6 months post-delivery...Maternal vaccination with an adenovirus-vector vaccine was well-tolerated and immunogenic in mothers and infants. These data could support the adoption of heterologous booster regimens during pregnancy and future adenovirus-vector vaccine development."

Journal • Infectious Disease • Novel Coronavirus Disease • Respiratory Diseases

Anti-SARS-CoV-2 Antibodies in Urine of Individuals Vaccinated with Janssen AD26.COV2.S COVID-19 Vaccine. (PubMed, Pathogens) - "(3) Findings indicate that urinary anti-SARS-CoV-2 antibodies reflect AD26.COV2.S vaccination and previous COVID-19. To further advance the methodology, studies with larger sample sizes and a greater diversity of COVID-19 vaccines are required."

Journal • Infectious Disease • Novel Coronavirus Disease • Respiratory Diseases