Low seropositivity and suboptimal neutralisation rates in patients fully vaccinated against COVID-19 with B-cell malignancies

COVID-19 vaccinated children, adolescents, and young adults with acute lymphoblastic leukemia show spike reactive antibodies and multifunctional T-cells

Little is known about the efficacy of COVID-19 vaccines during acute lymphoblastic leukemia therapy (ALL); data for COVID-19 vaccine immune responses in pediatric leukemia remain sparse. We conducted a single center study of patients aged 5-25 years undergoing ALL chemotherapy who received COVID-19 vaccination. Twenty-one patients were enrolled; efficacy was evaluable in 20. Twenty were vaccinated while receiving chemotherapy. Twenty received the BNT162b2 mRNA vaccine. Spike reactive antibodies (S-IgG) and/or T-cells (SRT) were detected in 16 of 20 (80%) vaccinated patients; 13 (65%) and 9 (45%) were positive for S-IgG and SRT, respectively. Six (30%) showed both spike reactive B and T-cell responses. Eleven of the 13 with S-IgG positivity were negative for anti-Nucleocapsid IgG, an antibody profile consistent with a vaccine induced immune response. All 13S-IgG+ patients showed neutralizing antibodies. SRT included CD4+ (7) and CD8+ (6) T-cells; both CD4+ and CD8+ SRT were seen in 4. SRT were multifunctional (producing multiple cytokines) in most patients (8 of 9); 4 showed SRT with triple cytokine and B-cell co-stimulatory responses, indicating a multimodal adaptive immune response. Immune responses were seen among patients vaccinated in the settings of lymphopenia (6 of 12) intensive chemotherapy (3 of 4), and Peg allergy (6 of 8). Sequencing revealed public CD4+ and CD8+ TCR sequences reactive to epitopes across the spike protein. In conclusion, COVID-19 vaccination induced B and/or T-cell responses in a majority of children and young adults undergoing ALL chemotherapy.

Chimeric antigen receptor-T-cell therapies going viral: latent and incidental viral infections

PURPOSE OF REVIEW

Infections are the leading cause of non-relapse mortality following chimeric antigen receptor (CAR)-T-cell therapy, with viral infections being frequent both in the early and late phases post-infusion. We review the epidemiology of viral infections and discuss critical approaches to prevention and management strategies in this setting.

RECENT FINDINGS

Herpesviruses dominate the early period. herpes simplex virus and varicella zoster virus infections are rare due to widespread antiviral prophylaxis, but cytomegalovirus (CMV) reactivation is increasingly observed, particularly in high-risk groups including B cell maturation antigen (BCMA)-CAR-T-cell therapy recipients and patients receiving corticosteroids. While CMV end-organ disease is rare, CMV is associated with increased mortality, emphasizing the need to evaluate the broader impact of CMV on long-term hematological, infection, and survival outcomes. Human herpesvirus-6 (HHV-6) has also emerged as a concern, with its diagnosis complicated by overlapping symptoms with neurotoxicity, underscoring the importance of considering viral encephalitis in differential diagnoses. Respiratory viruses are the most common late infections with a higher incidence after BCMA CAR-T-cell therapy. Vaccination remains a critical preventive measure against respiratory viruses but may be less immunogenic following CAR-T-cell therapy. The optimal timing, type of vaccine, and dosing schedule require further investigation.

SUMMARY

A better understanding of viral epidemiology and preventive trials are needed to improve infection prevention practices and outcomes following CAR-T-cell therapies.

Greater preservation of SARS-CoV-2 neutralising antibody responses following the ChAdOx1-S (AZD1222) vaccine compared with mRNA vaccines in haematopoietic cell transplant recipients

Whilst SARS-CoV-2 mRNA vaccines generate high neutralising antibodies (nAb) in most individuals, haematopoietic stem cell transplant (HSCT) and chimeric antigen receptor T-cell (CAR-T) recipients respond poorly. HSCT/CAR-T treatment ablates existing immune memory, with recipients requiring revaccination analogous to being vaccine naive. An optimal revaccination strategy for this cohort has not been defined. Factors predicting immunogenicity following three ancestral SARS-CoV-2 vaccines were assessed in 198 HSCT/CAR-T recipients and 96 healthcare workers (HCWs) recruited to multicentre studies. Only 25% of HSCT/CAR-T recipients generated nAbs following one dose, with titres 167-fold and 7-fold lower than that in HCWs after the first and second doses, respectively. Lower post-second dose nAb titres were associated with older age, rituximab use, and previous HSCT. ChAdOx1-S recipients were more likely to generate nAbs compared with mRNA vaccines, with titres comparable to HCWs. In contrast, nAbs were significantly lower in HSCT/CAR-T recipients than HCWs after mRNA vaccination. The poor first-dose immunogenicity in HSCT/CAR-T recipients suggests a minimum licensed dosing interval could limit the period of vulnerability following HSCT/CAR-T. The relative preservation of nAbs with ChAdOx1-S vaccination highlights the importance of evaluating alternative platforms to mRNA vaccination within this highly vulnerable clinical cohort.

Re-vaccination against SARS-CoV-2 in allogeneic HSCT patients: Repeated primary vaccine doses increase seroconversion rates

Patients with haematological malignancies often exhibit reduced antibody responses to severe acute respiratory syndrome-related coronavirus vaccines, especially those who have undergone allogeneic haematopoietic stem cell transplantation (HSCT). Limited data exist on vaccine efficacy in this group. In a retrospective analysis of 75 post-HSCT patients, we assessed serologic responses to one to four doses of Pfizer-BioNTech (PB), AstraZeneca (AZ) or Moderna (MU) vaccines within 2 years post-transplant. Seroconversion rates were 50.7%, 78%, 79% and 83% after the first to fourth doses respectively. The median time from allograft to first re-vaccination was 145 days (range 79-700). Failure to respond to the first vaccine dose was linked to acute GVHD (p = 0.042) and rituximab treatment within 12 months (p = 0.019). A trend was observed with chronic GVHD and seroconversion failure after the second (p = 0.07) and third (p = 0.09) doses. Patients vaccinated before HSCT showed better antibody responses post-transplant (p = 0.019). Coronavirus disease 2019 incidence was 16%, with 17% hospitalized and one death (8%). Despite low initial seroconversion rates post-HSCT, antibody responses improved after the second dose. Early full re-vaccination and boosters post-HSCT are recommended to reduce mortality. Rituximab use and active GVHD were identified as risk factors, warranting further investigation.

Vaccine schedule recommendations and updates for patients with hematologic malignancy post-hematopoietic cell transplant or CAR T-cell therapy

Revaccination after receipt of a hematopoietic cell transplant (HCT) or cellular therapies is a pillar of patient supportive care, with the potential to reduce morbidity and mortality linked to vaccine-preventable infections. This review synthesizes national, international, and expert consensus vaccination schedules post-HCT and presents evidence regarding the efficacy of newer vaccine formulations for pneumococcus, recombinant zoster vaccine, and coronavirus disease 2019 in patients with hematological malignancy. Revaccination post-cellular therapies are less well defined. This review highlights important considerations around poor vaccine response, seroprevalence preservation after cellular therapies, and the optimal timing of revaccination. Future research should assess the immunogenicity and real-world effectiveness of new vaccine formulations and/or vaccine schedules in patients post-HCT and cellular therapy, including analysis of vaccine response that relates to the target of cellular therapies.

Humoral and cellular responses to SARS-CoV-2 in patients with B-cell haematological malignancies improve with successive vaccination

Patients with haematological malignancies are more likely to have poor responses to vaccination. Here we provide detailed analysis of the humoral and cellular responses to COVID-19 vaccination in 69 patients with B-cell malignancies. Measurement of anti-spike IgG in serum demonstrated a low seroconversion rate with 27.1% and 46.8% of patients seroconverting after the first and second doses of vaccine, respectively. In vitro pseudoneutralisation assays demonstrated a poor neutralising response, with 12.5% and 29.5% of patients producing a measurable neutralising titre after the first and second doses, respectively. A third dose increased seropositivity to 54.3% and neutralisation to 51.5%, while a fourth dose further increased both seropositivity and neutralisation to 87.9%. Neutralisation titres post-fourth dose showed a positive correlation with the size of the B-cell population measured by flow cytometry, suggesting an improved response correlating with recovery of the B-cell compartment after B-cell depletion treatments. In contrast, interferon gamma ELISpot analysis showed a largely intact T-cell response, with the percentage of patients producing a measurable response boosted by the second dose to 75.5%. This response was maintained thereafter, with only a small increase following the third and fourth doses, irrespective of the serological response at these timepoints.

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.

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.

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.

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.

Serologic response and safety of COVID-19 vaccination in HSCT or CAR T-cell recipients: a systematic review and meta-analysis

Background

Patients receiving hematopoietic stem cell transplantation (HSCT) or chimeric antigen receptor T cell (CAR T-cell) therapy are immunocompromised and at high risk of viral infection, including SAR2-CoV-2 infection. However, the effectiveness and safety of COVID-19 vaccines in these recipients is not well characterized. The present meta-analysis evaluated the serologic response and safety of COVID-19 vaccines in these population.

Methods

Literature databases (MEDLINE, EMBASE, Web of Science, MedRvix and BioRvix) were searched for original studies with serologic response post COVID-19 vaccination in HSCT or CAR T-cell recipients published until July 14, 2022. The analysis included 27 observational studies with a total of 2899 patients receiving allogeneic HSCT (2506), autologous HSCT (286) or CAR T-cell therapy (107), and 683 healthy participants with serologic response data. Random effects models were used to pool the rate of serologic response to COVID-19 vaccination in HSCT or CAR T-cell recipients and odds ratio comparing with healthy controls.

Results

The pooled seropositivity rates in HSCT and CAR T-cell recipients were 0.624 [0.506–0.729] for one dose, 0.745 [0.712–0.776] for two doses. The rates were significantly lower than those in healthy controls (nearly 100%). In subgroup analysis, CAR T-cell recipients exhibited an even lower seroconversion rate (one dose: 0.204 [0.094–0.386]; two doses: 0.277 [0.190–0.386]) than HSCT counterparts (one dose: 0.779 [0.666–0.862]; two doses: 0.793 [0.762–0.821]). The rates were comparable between autologous and allogeneic HSCT recipients. Other possible impact factors related to seropositivity were time interval between therapy and vaccination, use of immunosuppressive drugs and immune cell counts. Most vaccine-related adverse effects were mild and resolvable, comparable to general population.

Conclusions

This analysis revealed a diminished response to COVID-19 vaccines in HSCT or CAR T-cell recipients. Our findings may inform regular COVID-19 vaccination at appropriate intervals after HSCT or CAR T-cell therapy.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40164-022-00299-6.

The burden of SARS-CoV-2 in patients receiving chimeric antigen receptor T cell immunotherapy: everything to lose

INTRODUCTION

Chimeric antigen receptor T (CAR-T) cell immunotherapy has revolutionized the prognosis of refractory or relapsed B-cell malignancies. CAR-T cell recipients have immunosuppression generated by B-cell aplasia leading to a higher susceptibility to respiratory virus infections and poor response to vaccination.

AREAS COVERED

This review focuses on the challenge posed by B-cell targeted immunotherapies: managing long-lasting B-cell impairment during the successive surges of a deadly viral pandemic. We restricted this report to data regarding vaccine efficacy in CAR-T cell recipients, outcomes after developing COVID-19 and specificities of treatment management. We searched in MEDLINE database to identify relevant studies until March 31^st 2022.

EXPERT OPINION

Among available observational studies, the pooled mortality rate reached 40% in CAR-T cell recipients infected by SARS-CoV-2. Additionally, vaccines responses seem to be widely impaired in recipients (seroconversion 20%, T-cell response 50%). In this setting of B-cell depletion, passive immunotherapy is the backbone of treatment. Convalescent plasma therapy has proven to be a highly effective curative treatment with rare adverse events. Neutralizing monoclonal antibodies could be used as pre-exposure prophylaxis or early treatment but their neutralizing activity is constantly challenged by new variants. In order to reduce viral replication, direct-acting antiviral drugs should be considered.

Immunogenicity of COVID-19 Vaccines in Patients with Diverse Health Conditions: a Comprehensive Systematic Review

It remains unclear how effective COVID-19 vaccinations will be in patients with weakened immunity due to diseases, transplantation, and dialysis. We conducted a systematic review comparing the efficacy of COVID-19 vaccination in patients with solid tumor, hematologic malignancy, autoimmune disease, inflammatory bowel disease, and patients who received transplantation or dialysis. A literature search was conducted twice using the Medline/PubMed database. As a result, 21 papers were included in the review, and seropositivity rate was summarized by specific type of disease, transplantation, and dialysis. When different papers studied the same type of patient group, a study with a higher number of participants was selected. Most of the solid tumor patients showed a seropositivity rate of more than 80% after the second inoculation, but a low seropositivity was found in certain tumors such as breast cancer. Research in patients with certain types of hematological malignancy and autoimmune diseases has also reported low seropositivity, and this may have been affected by the immunosuppressive treatment these patients receive. Research in patients receiving dialysis or transplantation has reported lower seropositivity rates than the general population, while all patients with inflammatory bowel disease have converted to be seropositive. Meta-analysis validating these results will be needed, and studies will also be needed on methods to protect patients with reduced immunity from COVID-19. This article is protected by copyright. All rights reserved.

Coronavirus disease 2019 in patients with inborn errors of immunity: lessons learned

PURPOSE OF REVIEW

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has caused extreme concern for patients with inborn errors of immunity (IEIs). In the first 6  months of the pandemic, the case fatality rate among patients with IEIs resembled that of the general population (9%). This review aims at summarizing what we have learned about the course and outcome of coronavirus disease 2019 (COVID-19) in patients with different IEIs and what this can potentially teach us about the immune mechanisms that could confer protection or predisposition to severe disease.

RECENT FINDINGS

A total of 649 patients with IEI and COVID-19 have been reported in the last year and a half, spanning all groups of the International Union of Immunological Societies classification of IEIs. For most patients, the underlying IEI does not represent an independent risk factor for severe COVID-19. In fact, some IEI may even be protective against the severe disease due to impaired inflammation resulting in less immune-mediated collateral tissue damage.

SUMMARY

We review the characteristics of SARS-CoV-2 infection in a large number of patients with IEI. Overall, we found that combined immunodeficiencies, immune dysregulation disorders, and innate immune defects impairing type I interferon responses are associated with severe disease course.

Reasons and consequences of COVID-19 vaccine failure in patients with chronic lymphocytic leukemia

People with hematologic malignancies are at a high risk of morbidity and mortality from COVID-19. The response to vaccination is highly limited in patients with chronic lymphocytic leukemia. Less than half of the patients develop antibody response, suggesting that they remain at risk of SARS-CoV-2 infection even after the vaccination. Reasons for inadequate response to COVID-19 vaccination in chronic lymphocytic leukemia are multifactorial and attributed to disease-related immune dysregulation and patient- and therapy-related factors. The negative predictors of response to vaccination include hypogammaglobulinemia, advanced age, current active treatment, and past treatment anti-CD20 monoclonal antibodies. Despite using booster doses and heterologous immunization to improve humoral and cellular immunity, some patients with chronic lymphocytic leukemia will fail to respond. Active treatment at the time of vaccination and a recent history of anti-CD20 monoclonal antibodies use are the strongest predictors of the non-response. Current data support informing patients with chronic lymphocytic leukemia and other hematologic malignancies about the risk of infection regardless of vaccination. These individuals and members of their households should continue extreme preventive actions despite relaxed local regulations. Other emerging non-vaccine preventive strategies include passive and post-exposure prevention with monoclonal antibodies.