Preexisting and Post-COVID-19 Immune Responses to SARS-CoV-2 in Patients with Cancer

COVID-19 in patients receiving treatment at an outpatient chemotherapy unit

During the COVID-19 pandemic period, many patients who required outpatient chemotherapy developed COVID-19, requiring chemotherapy interruption. However, there are no clear guidelines regarding the safe timing for restarting chemotherapy. We conducted a retrospective study to assess when such patients can safely recommence chemotherapy. Of the 40 patients included in this study, 34 restarted anticancer drug therapy after COVID-19 infection. Six patients, four with multiple myeloma, and one each with follicular lymphoma and glioma, remained SARS-CoV-2 antigen positive >20 days after COVID-19 onset. Multiple myeloma patients recorded significantly higher frequencies of SARS-CoV-2 antigen positivity >20 days after COVID-19 onset compared with solid tumor patients, with no significant differences in the frequency of SARS-CoV-2 positivity during 5-20 days from COVID-19 onset between them. According to our data, most solid tumor patients achieved SARS-CoV-2 antigen negativity after 20 days from COVID-19 onset. On the other hand, multiple myeloma patients might need serial antigen tests before restarting anticancer therapy in the outpatient chemotherapy setting.

Linking COVID-19 and cancer: Underlying mechanism

COVID-19 caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), lead to a global health crisis with a spectrum of clinical manifestations. A potentially vulnerable category for SARS-CoV-2 infection was identified in patients with other medical conditions. Intriguingly, parallels exist between COVID-19 and cancer at the pathophysiological level, suggesting a possible connection between them. This review discusses all possible associations between COVID-19 and cancer. Expression of receptors like angiotensin-converting enzyme 2 (ACE2) and transmembrane protease serine 2 (TMPRSS2) increases COVID-19 susceptibility. SARS-CoV-2 infection might increase cancer susceptibility and accelerate cancer progression through mechanisms involving cytokine storm, tissue hypoxia, impaired T-cell responses, autophagy, neutrophil activation, and oxidative stress. These mechanisms collectively contribute to immune suppression, hindered apoptosis, and altered cellular signaling in the tumor microenvironment, creating conditions favorable for tumor growth, metastasis, and recurrence. Approved vaccines and their impact on cancer patients along-with new clinical trials are also described.

Tixagevimab/Cilgavimab for COVID-19 Pre-Exposure Prophylaxis in Hematologic Patients-A Tailored Approach Based on SARS-CoV-2 Vaccine Response

Patients with hematologic malignancies still face a significant risk of severe coronavirus disease 2019 (COVID-19). The severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2)-neutralizing monoclonal antibody combination tixagevimab/cilgavimab (TIX/CGB) could be administered to immunocompromised patients for pre-exposure prophylaxis (PrEP) before the emergence of TIX/CGB-resistant COVID-19 Omicron variants. TIX/CGB application could be carried out regardless of the host's immune response to previous active SARS-CoV-2 vaccinations or infections. Because the efficacy of COVID-19 PrEP remains unclear, especially in SARS-CoV-2-seropositive patients, German national guidelines recommended TIX/CGB PrEP only for SARS-CoV-2-seronegative patients in addition to an intensified active vaccination schedule. Having followed these guidelines, we now report the characteristics and outcomes of 54 recipients of TIX/CGB PrEP in SARS-CoV-2-seronegative patients with hematological disease from a German tertiary medical center and compare them to 125 seropositive patients who did not receive any PrEP. While the number of patients with B-cell lymphomas was significantly higher in the seronegative cohort (33 (61%) vs. 18 (14%) cases, p < 0.01), patients with myeloid diseases were significantly more frequent in the seropositive cohort (51 (41%) vs. 5 (9%) cases, p < 0.01). Strikingly, patients who had undergone allogeneic hematopoietic stem cell transplantation were significantly more likely (forty-nine (39%) vs. six (11%) cases, p < 0.01) to be SARS-CoV-2 seropositive. We observed that prophylactic application of TIX/CGB PrEP to a highly vulnerable group of SARS-CoV-2-seronegative patients resulted in a similar number of COVID-19 breakthrough infections compared to the untreated seropositive control group (16 (32%) vs. 39 (36%), p = 0.62) and comparable COVID-19-related outcomes like hospitalization and oxygen requirement throughout an extended follow-up period of 12 months. In conclusion, our results support the tailored approach of administering TIX/CGB PrEP only to SARS-CoV-2-seronegative patients during the COVID-19 pandemic and might provide a rationale for similar strategies during future outbreaks/diseases, especially in times of initial limited availability and/or financial constraints.

Clinical efficacy of prophylactic intravenous immunoglobulin for elderly DLBCL patients with hypogammaglobulinemia in the COVID-19 pandemic era

Background

Elderly patients diagnosed with diffuse large B-cell lymphoma (DLBCL) undergoing reduced intensity R-CHOP therapy are at a heightened risk of acquiring infections, notably coronavirus disease 2019 (COVID-19) infection. This study aimed to evaluate the efficacy of intravenous immunoglobulin (IVIG) as prophylaxis against COVID-19 in this vulnerable population.

Methods

A total of 125 elderly patients with DLBCL undergoing reduced intensity R-CHOP therapy were analyzed in this prospective, multicenter study. Patients with hypogammaglobulinemia were categorized into IVIG and non-IVIG groups, while those with normal immunoglobulin levels constituted the observation group. The study evaluated COVID-19 infection rates, therapy response, and safety outcomes.

Results

Among the enrolled patients (median age: 77 years), 89 patients (71.2%) presented with hypogammaglobulinemia at diagnosis, and 56 patients enrolled in the IVIG administration group. IVIG administration remarkably reduced COVID-19 infection rates compared to non-IVIG recipients (8.9% vs. 24.6%; p =0.040). Notably, patients over 80 years old were more susceptible to COVID-19. Patients on IVIG exhibited good tolerance with manageable adverse events. Among patients with hypogammaglobulinemia who received IVIG, 40.5% of patients developed additional immunoglobulin deficiencies during chemotherapy. One or more new hypogammaglobulinemia occurred during chemotherapy in 72% of patients with hypogammaglobulinemia who did not receive IVIG, and in 61.3% of patients who did not have hypogammaglobulinemia at diagnosis.

Conclusion

IVIG showed promise in reducing COVID-19 infections among elderly patients with DLBCL receiving reduced intensity R-CHOP therapy. This highlights IVIG's potential as a prophylactic measure, necessitating further investigation to optimize dosing, administration schedules, and potential interactions with vaccination strategies.

Decoding Immuno-Competence: A Novel Analysis of Complete Blood Cell Count Data in COVID-19 Outcomes

BACKGROUND

While 'immuno-competence' is a well-known term, it lacks an operational definition. To address this omission, this study explored whether the temporal and structured data of the complete blood cell count (CBC) can rapidly estimate immuno-competence. To this end, one or more ratios that included data on all monocytes, lymphocytes and neutrophils were investigated.

MATERIALS AND METHODS

Longitudinal CBC data collected from 101 COVID-19 patients (291 observations) were analyzed. Dynamics were estimated with several approaches, which included non-structured (the classic CBC format) and structured data. Structured data were assessed as complex ratios that capture multicellular interactions among leukocytes. In comparing survivors with non-survivors, the hypothesis that immuno-competence may exhibit feedback-like (oscillatory or cyclic) responses was tested.

RESULTS

While non-structured data did not distinguish survivors from non-survivors, structured data revealed immunological and statistical differences between outcomes: while survivors exhibited oscillatory data patterns, non-survivors did not. In survivors, many variables (including IL-6, hemoglobin and several complex indicators) showed values above or below the levels observed on day 1 of the hospitalization period, displaying L-shaped data distributions (positive kurtosis). In contrast, non-survivors did not exhibit kurtosis. Three immunologically defined data subsets included only survivors. Because information was based on visual patterns generated in real time, this method can, potentially, provide information rapidly.

DISCUSSION

The hypothesis that immuno-competence expresses feedback-like loops when immunological data are structured was not rejected. This function seemed to be impaired in immuno-suppressed individuals. While this method rapidly informs, it is only a guide that, to be confirmed, requires additional tests. Despite this limitation, the fact that three protective (survival-associated) immunological data subsets were observed since day 1 supports many clinical decisions, including the early and personalized prognosis and identification of targets that immunomodulatory therapies could pursue. Because it extracts more information from the same data, structured data may replace the century-old format of the CBC.

Serological Responses and Predictive Factors of Booster COVID-19 Vaccines in Patients with Hematologic Malignancies

Patients with hematologic malignancies are reported to have a more severe course of coronavirus disease 2019 (COVID-19) and be less responsive to vaccination. In this prospective study, we aimed to evaluate the serological responses to booster COVID-19 vaccines of Taiwanese patients with hematologic malignancies and identify potential predictive markers for effective neutralizing immunity. This study enrolled 68 patients with hematologic malignancies and 68 age- and gender-matched healthy control subjects who received three doses of vaccination against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) from 1 January 2022 to 31 October 2022. The SARS-CoV-2 immunoglobulin G (IgG) spike antibody level was measured with the Abbott assay. The effective neutralization capacity was defined as an anti-spike IgG level of ≥4160 AU/mL. Among the 68 patients with hematologic malignancies, 89.7% achieved seroconversion after booster doses. Seven patients with actively treated lymphoma remained seronegative and had the lowest humoral responses among patients with different types of hematologic malignancies. Despite comparable antibody titers between patients and healthy individuals, rates of effective neutralization (66.2% vs. 86.8%, respectively; p = 0.005) were significantly reduced in patients with hematologic malignancies. In a multivariate analysis, the independent predictors for effective neutralization were a lack of B-cell-targeted agents within six months of vaccination (odds ratio, 15.2; 95% confidence interval, 2.7-84.2; p = 0.002) and higher immunoglobulin levels (odds ratio, 4.4; 95% confidence interval, 1.3-14.7; p = 0.017). In conclusion, the majority of patients with hematologic malignancies achieved seroconversion after booster vaccination. Patients with ongoing B-cell depletion and hypogammaglobinemia were identified as having negative predictive markers for effective neutralization.

Phase I/II trial of a peptide-based COVID-19 T-cell activator in patients with B-cell deficiency

T-cell immunity is central for control of COVID-19, particularly in patients incapable of mounting antibody responses. CoVac-1 is a peptide-based T-cell activator composed of SARS-CoV-2 epitopes with documented favorable safety profile and efficacy in terms of SARS-CoV-2-specific T-cell response. We here report a Phase I/II open-label trial (NCT04954469) in 54 patients with congenital or acquired B-cell deficiency receiving one subcutaneous CoVac-1 dose. Immunogenicity in terms of CoVac-1-induced T-cell responses and safety are the primary and secondary endpoints, respectively. No serious or grade 4 CoVac-1-related adverse events have been observed. Expected local granuloma formation has been observed in 94% of study subjects, whereas systemic reactogenicity has been mild or absent. SARS-CoV-2-specific T-cell responses have been induced in 86% of patients and are directed to multiple CoVac-1 peptides, not affected by any current Omicron variants and mediated by multifunctional T-helper 1 CD4+ T cells. CoVac-1-induced T-cell responses have exceeded those directed to the spike protein after mRNA-based vaccination of B-cell deficient patients and immunocompetent COVID-19 convalescents with and without seroconversion. Overall, our data show that CoVac-1 induces broad and potent T-cell responses in patients with B-cell/antibody deficiency with a favorable safety profile, which warrants advancement to pivotal Phase III safety and efficacy evaluation. ClinicalTrials.gov identifier NCT04954469.

Comparative Assessment of the Kinetics of Cellular and Humoral Immune Responses to COVID-19 Vaccination in Cancer Patients

OBJECTIVE

The kinetics of immune responses to various SARS-CoV-2 vaccines in cancer patients were investigated.

METHODS

In total, 57 cancer patients who received BNT162b2-RNA or BBIBP-CorV vaccines were enrolled. Cellular and humoral immunity were assessed at three-time points, before the first vaccine dose and 14-21 days after the first and second doses. Chemiluminescent microparticle immunoassay was used to evaluate SARS-CoV-2 anti-spike IgG response, and QuantiFERON^® SARS-CoV-2 kit assessed T-cell response.

RESULTS

Data showed that cancer patients' CD4⁺ and CD8⁺ T cell-median IFN-γ secretion of SARS-CoV-2 antigens increased after the first and second vaccine doses (p = 0.027 and p = 0.042). BNT162b2 vaccinees had significantly higher IFN-γ levels to CD4⁺ and CD8⁺ T cell epitopes than BBIBP-CorV vaccinees (p = 0.028). There was a positive correlation between IgG antibody titer and T cell response regardless of vaccine type (p < 0.05).

CONCLUSIONS

This study is one of the first to investigate cellular and humoral immune responses to SARS-CoV-2 immunization in cancer patients on active therapy after each vaccine dose. COVID-19 immunizations helped cancer patients develop an effective immune response. Understanding the cellular and humoral immune response to COVID-19 in cancer patients undergoing active treatment is necessary to improve vaccines and avoid future SARS pandemics.

Tixagevimab/Cilgavimab as pre-exposure prophylaxis against SARS-CoV-2 in patients with hematological malignancies

The approved combination of Tixagevimab/Cilgavimab has been shown to decrease the rate of symptomatic SARS-CoV-2 infection in patients at increased risk of inadequate response to vaccination. However, Tixagevimab/Cilgavimab was tested in a few studies that included patients with hematological malignancies, even if this population has shown an increased risk of unfavorable outcomes following infection (with high rates of hospitalization, intensive care unit admission, and mortality) and poor significant immunization following vaccines. We performed a real-life prospective cohort study to evaluate the rate of SARS-CoV-2 infection following pre-exposure prophylaxis with Tixagevimab/Cilgavimab in anti-spike seronegative patients compared to a cohort of seropositive patients who were observed or received a fourth vaccine dose. We recruited 103 patients with a mean age of 67 years: 35 (34%) received Tixagevimab/Cilgavimab and were followed from March 17, 2022, until November 15, 2022. After a median follow-up of 4.24 months, the 3-month cumulative incidence of infection was 20% versus 12% in the Tixagevimab/Cilgavimab and observation/vaccine groups respectively (HR 1.57; 95% CI: 0.65-3.56; p = 0.34). In this study, we report our experience with Tixagevimab/Cilgavimab and a tailored approach to SARS-CoV-2 infection prevention in patients with hematological malignancies during the SARS-CoV-2 omicron surge.

COVID-19 in cancer patients: update from the joint analysis of the ESMO-CoCARE, BSMO, and PSMO international databases

BACKGROUND

COVID-19 has significantly affected patients with cancer and revealed unanticipated challenges in securing optimal cancer care across different disciplines. The European Society for Medical Oncology COVID-19 and CAncer REgistry (ESMO-CoCARE) is an international, real-world database, collecting data on the natural history, management, and outcomes of patients with cancer and SARS-CoV-2 infection.

METHODS

This is the 2nd CoCARE analysis, jointly with Belgian (Belgian Society of Medical Oncology, BSMO) and Portuguese (Portuguese Society of Medical Oncology, PSMO) registries, with data from January 2020 to December 2021. The aim is to identify significant prognostic factors for COVID-19 hospitalization and mortality (primary outcomes), as well as intensive care unit admission and overall survival (OS) (secondary outcomes). Subgroup analyses by pandemic phase and vaccination status were carried out.

RESULTS

The cohort includes 3294 patients (CoCARE: 2049; BSMO: 928, all hospitalized by eligibility criteria; PSMO: 317), diagnosed in four distinct pandemic phases (January to May 2020: 36%; June to September 2020: 9%; October 2020 to February 2021: 41%; March to December 2021: 12%). COVID-19 hospitalization rate was 54% (CoCARE/PSMO), ICU admission 14%, and COVID-19 mortality 22% (all data). At a 6-month median follow-up, 1013 deaths were recorded with 73% 3-month OS rate. No significant change was observed in COVID-19 mortality among hospitalized patients across the four pandemic phases (30%-33%). Hospitalizations and ICU admission decreased significantly (from 78% to 34% and 16% to 10%, respectively). Among 1522 patients with known vaccination status at COVID-19 diagnosis, 70% were non-vaccinated, 24% had incomplete vaccination, and 7% complete vaccination. Complete vaccination had a protective effect on hospitalization (odds ratio = 0.24; 95% confidence interval [0.14-0.38]), ICU admission (odds ratio = 0.29 [0.09-0.94]), and OS (hazard ratio = 0.39 [0.20-0.76]). In multivariable analyses, COVID-19 hospitalization was associated with patient/cancer characteristics, the first pandemic phase, the presence of COVID-19-related symptoms or inflammatory biomarkers, whereas COVID-19 mortality was significantly higher in symptomatic patients, males, older age, ethnicity other than Asian/Caucasian, Eastern Cooperative Oncology Group performance status ≥2, body mass index <25, hematological malignancy, progressive disease versus no evident disease, and advanced cancer stage.

CONCLUSIONS

The updated CoCARE analysis, jointly with BSMO and PSMO, highlights factors that significantly affect COVID-19 outcomes, providing actionable clues for further reducing mortality.

SARS-CoV-2-Specific T Cell Responses in Immunocompromised Individuals with Cancer, HIV or Solid Organ Transplants

Adaptive immune responses play an important role in the clinical course of SARS-CoV-2 infection. While evaluations of the virus-specific defense often focus on the humoral response, cellular immunity is crucial for the successful control of infection, with the early development of cytotoxic T cells being linked to efficient viral clearance. Vaccination against SARS-CoV-2 induces both CD4+ and CD8+ T cell responses and permits protection from severe COVID-19, including infection with the currently circulating variants of concern. Nevertheless, in immunocompromised individuals, first data imply significantly impaired SARS-CoV-2-specific immune responses after both natural infection and vaccination. Hence, these high-risk groups require particular consideration, not only in routine clinical practice, but also in the development of future vaccination strategies. In order to assist physicians in the guidance of immunocompromised patients, concerning the management of infection or the benefit of (booster) vaccinations, this review aims to provide a concise overview of the current knowledge about SARS-CoV-2-specific cellular immune responses in the vulnerable cohorts of cancer patients, people living with HIV (PLWH), and solid organ transplant recipients (SOT). Recent findings regarding the virus-specific cellular immunity in these differently immunocompromised populations might influence clinical decision-making in the future.

Anti-SARS-CoV-2 antibody-containing plasma improves outcome in patients with hematologic or solid cancer and severe COVID-19: a randomized clinical trial

Patients with cancer are at high risk of severe coronavirus disease 2019 (COVID-19), with high morbidity and mortality. Furthermore, impaired humoral response renders severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines less effective and treatment options are scarce. Randomized trials using convalescent plasma are missing for high-risk patients. Here, we performed a randomized, open-label, multicenter trial ( https://www.clinicaltrialsregister.eu/ctr-search/trial/2020-001632-10/DE ) in hospitalized patients with severe COVID-19 (n = 134) within four risk groups ((1) cancer (n = 56); (2) immunosuppression (n = 16); (3) laboratory-based risk factors (n = 36); and (4) advanced age (n = 26)) randomized to standard of care (control arm) or standard of care plus convalescent/vaccinated anti-SARS-CoV-2 plasma (plasma arm). No serious adverse events were observed related to the plasma treatment. Clinical improvement as the primary outcome was assessed using a seven-point ordinal scale. Secondary outcomes were time to discharge and overall survival. For the four groups combined, those receiving plasma did not improve clinically compared with those in the control arm (hazard ratio (HR) = 1.29; P = 0.205). However, patients with cancer experienced a shortened median time to improvement (HR = 2.50; P = 0.003) and superior survival with plasma treatment versus the control arm (HR = 0.28; P = 0.042). Neutralizing antibody activity increased in the plasma cohort but not in the control cohort of patients with cancer (P = 0.001). Taken together, convalescent/vaccinated plasma may improve COVID-19 outcomes in patients with cancer who are unable to intrinsically generate an adequate immune response.

Immune Profiling Uncovers Memory T-Cell Responses with a Th17 Signature in Cancer Patients with Previous SARS CoV-2 Infection Followed by mRNA Vaccination

Simple Summary

Cancer patients are considered a high-risk group for infectious diseases including COVID-19. The protective effects of vaccination are unclear in oncologic patients, as well as their duration. In this study antibody, T-cell and myeloid cell immunity were evaluated in three cohorts of healthy donors and oncologic patients, including those infected with SARS-CoV-2, BNT162b2-vaccinated (mRNA vaccine), and with previous COVID-19 and subsequently vaccinated. We concluded that vaccination was a poor inductor of cellular immunity towards the S protein. Memory T-cells were only detected in patients and healthy donors with COVID-19 previous to vaccination but with an accentuated Th17 inflammatory profile, together with elevated numbers of circulating neutrophils.

Abstract

It is unclear whether patients with cancer present inherently impaired responses to COVID-19 and vaccination due to their treatments, neoplastic diseases or both. To address this question, immune profiling was performed in three cohorts of healthy donors and oncologic patients: infected with SARS-CoV-2, BNT162b2-vaccinated, and with previous COVID-19 disease and subsequently vaccinated. Cancer patients showed good antibody responses to vaccination, but poor induction of T-cell responses towards the S protein when compared to infection. Following natural infection, the major targets for T-cells were the SARS-CoV-2 structural proteins M and S, but not the N protein. Similar to antibody titers, the T-cell responses quickly decayed after six months post-vaccination. Significant memory T-cell expansion was observed in vaccinated donors only if previously diagnosed with COVID-19 before undergoing vaccination. Oncologic patients with previous COVID-19 followed by vaccination exhibited potent IL-17+ CD4 and CD8 T-cell responses and elevated numbers of circulating neutrophils in peripheral blood.

T cells in SARS-CoV-2 infection and vaccination

While antibodies garner the lion’s share of attention in SARS-CoV-2 immunity, cellular immunity (T cells) may be equally, if not more important, in controlling infection. Both CD8⁺ and CD4⁺ T cells are elicited earlier and are associated with milder disease, than antibodies, and T-cell activation appears to be necessary for control of infection. Variants of concern (VOCs) such as Omicron have escaped the neutralizing antibody responses after two mRNA vaccine doses, but T-cell immunity is largely intact. The breadth and patient-specific nature of the latter offers a formidable line of defense that can limit the severity of illness, and are likely to be responsible for most of the protection from natural infection or vaccination against VOCs which have evaded the antibody response. Comprehensive searches for T-cell epitopes, T-cell activation from infection and vaccination of specific patient groups, and elicitation of cellular immunity by various alternative vaccine modalities are here reviewed. Development of vaccines that specifically target T cells is called for, to meet the needs of patient groups for whom cellular immunity is weaker, such as the elderly and the immunosuppressed. While VOCs have not yet fully escaped T-cell immunity elicited by natural infection and vaccines, some early reports of partial escape suggest that future VOCs may achieve the dreaded result, dislodging a substantial proportion of cellular immunity, enough to cause a grave public health burden. A proactive, rather than reactive, solution which identifies and targets immutable sequences in SARS-CoV-2, not just those which are conserved, may be the only recourse humankind has to disarm these future VOCs before they disarm us.

Humoral and cellular responses to mRNA-based COVID-19 booster vaccinations in patients with solid neoplasms under active treatment

Background

Patients with cancer are at high risk for severe coronavirus disease 2019 (COVID-19) infection. Knowledge regarding the efficacy of the messenger RNA (mRNA) vaccines in actively treated cancer patients is limited as they had been excluded from the pivotal studies of these vaccines. We evaluated humoral and cellular immune responses in cancer patients after double vaccination and a booster dose and identified disease- and treatment-related factors associated with a reduced immune response. We also documented the number and outcome of breakthrough infections.

Patients and methods

Patients with metastatic solid malignancies undergoing active treatment were included if they had received two doses of the severe acute respiratory syndrome coronavirus 2 mRNA vaccines BNT162b2 or mRNA-1273 and a booster dose. Other causes of immunosuppression and previous COVID-19 infections (positive anti-nucleocapsid titers) were exclusion criteria. Anti-spike antibodies, neutralizing antibodies (nAbs) and T-cell responses were assessed about 6 months after the two-dose vaccination and 4 weeks after the booster.

Results

Fifty-one patients had pre-booster and 46 post-booster measurements. Anti-spike titers after two vaccine doses were highly variable and significantly lower in older patients, during treatment with chemotherapy compared to targeted and endocrine treatments and in patients with low CD4+ or CD19+ cell counts. The booster dose led to a significant increase in anti-spike antibodies and nAbs, achieving almost uniformly high titers, irrespective of baseline and treatment factors. The cellular immune response was also significantly increased by the booster, however generally more stable and not influenced by baseline factors and treatment type. Seventeen patients (33%) experienced breakthrough infections, but none required hospital care or died from COVID-19.

Conclusions

An mRNA vaccine booster dose is able to increase humoral and cellular immune responses and to overcome the immunosuppressive influence of baseline and treatment factors in cancer patients. Breakthrough infections were uniformly mild in this vaccinated high-risk population.

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We provide data on humoral and cellular immunity after SARS-CoV-2 mRNA vaccination in actively treated cancer patients.

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We found highly variable anti-S titers after two doses; titers were influenced by several baseline and treatment factors.

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The booster achieved uniformly higher anti-S titers; the influence of baseline factors could be overcome by the booster.

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Spike-specific T-cell immunity was more stable and not influenced by baseline factors.

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Even though many breakthrough infections were recorded during the Omicron wave, they were uniformly mild.

Development of Approaches and Metrics to Measure the Impact and Improve the Clinical Outcomes of Patients With Frailty in the Era of COVID-19. The COMETA Italian Protocol

The outbreak of the coronavirus 2 disease 2019 (COVID-19) puts an enormous burden on healthcare systems worldwide. This may worsen outcomes in patients with severe chronic diseases such as cancer, autoimmune diseases, and immune deficiencies. In this critical situation, only a few available data exist, which do not allow us to provide practical guides for the treatment of oncological or immunocompromised patients. Therefore, a further step forward is needed, addressing the specific needs and demands of frail patients in the pandemic era. Here we aim to present a protocol of a study approved by an ethical committee named "CO.M.E.TA". CO.M.E.TA protocol is a network project involving six Italian institutions and its goals are: i) to measure and compare the impact of the pandemic on the access of cancer and immunocompromised patients to therapies in three Italian regions; ii) to assess how reorganizational measures put in place in these different institutions have impacted specific metrics of performance; iii) to establish a COVID-19 Biobank of biological samples from SARS-CoV-2 infected patients to be used to study immunological alterations in patients with immune frailty.

COVID-19 in patients with hematologic malignancy

The coronavirus infectious disease (COVID-19) shows a remarkable symptomatic heterogeneity. Several risk factors including advanced age, previous illnesses and a compromised immune system contribute to an unfavorable outcome. In patients with hematologic malignancy, the immune response to severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) is significantly reduced explaining why the mortality rate of hematologic patients hospitalized for a SARS-CoV-2 infection is about 34%. Active immunization is an essential pillar to prevent SARS-CoV-2 infections in patients with hematologic malignancy. However, the immune response to SARS-CoV-2 vaccines may be significantly impaired, as only half of patients with hematologic malignancy develop a measurable anti-viral antibody response. The subtype of hematologic malignancy and B-cell depleting treatment predict a poor immune response to vaccination. Recently, antiviral drugs and monoclonal antibodies for pre-exposure or post-exposure prophylaxis and for early treatment of COVID-19 have become available. These therapies should be offered to patients at high risk for severe COVID-19 and vaccine non-responder. Importantly, as the virus evolves, some therapies may lose their clinical efficacy against new variants. Therefore, the ongoing pandemic will remain a major challenge for patients with hematologic malignancy and their caregivers who need to constantly monitor the scientific progress in this area.

Prevalence of COVID-19-associated symptoms during acute infection in relation to SARS-CoV-2-directed humoral and cellular immune responses in a mild-diseased convalescent cohort

Objectives

Besides SARS-CoV-2-directed humoral immune responses, T cell responses are indispensable for effective antiviral immunity. Recent data have shown a correlation between COVID-19 symptoms and humoral immune response, but so far, little is known about the association of SARS-CoV-2-directed T cell responses and disease severity. Herein, we evaluated the prevalence of different clinical COVID-19 symptoms in relation to SARS-CoV-2-directed humoral and cellular immune responses.

Methods

The severity of eight different symptoms during acute infection were assessed using questionnaires from 193 convalescent individuals and were evaluated in relation to SARS-CoV-2 antibody levels and intensity of SARS-CoV-2-specific T cell responses 2–8 weeks after positive polymerase chain reaction.

Results

Although increased IgG serum levels could be associated with severity of most symptoms, no difference in T cell response intensity between different symptom severities was observed for the majority of COVID-19 symptoms. However, when analyzing loss of smell or taste and cough, awareness of more severe symptoms was associated with reduced T cell response intensities.

Conclusions

These data suggest that rapid virus clearance mediated by SARS-CoV-2-specific T cells prevents severe symptoms of COVID-19.

CD8+ T Cells in SARS-CoV-2 Induced Disease and Cancer-Clinical Perspectives

Dysregulated innate and adaptive immunity is a sign of SARS-CoV-2-induced disease and cancer. CD8+ T cells are important cells of the immune system. The cells belong to the adaptive immunity and take a front-line defense against viral infections and cancer. Extreme CD8+ T-cell activities in the lung of patients with a SARS-CoV-2-induced disease and within the tumor microenvironment (TME) will change their functionality into exhausted state and undergo apoptosis. Such diminished immunity will put cancer cases at a high-risk group for SARS-CoV-2-induced disease, rendering viral sepsis and a more severe condition which will finally cause a higher rate of mortality. Recovering responses from CD8+ T cells is a purpose of vaccination against SARS-CoV-2. The aim of this review is to discuss the CD8+ T cellular state in SARS-CoV-2-induced disease and in cancer and to present some strategies for recovering the functionality of these critical cells.

Reduced Absolute Count of Monocytes in Patients Carrying Hematological Neoplasms and SARS-CoV2 Infection

Simple Summary

In hematological neoplasms associated with COVID-19, immunological dysfunction, including reduced count of non-classical monocytes, has been suggested as a primary driver of morbidity and mortality. In this work, we investigated the contribution of absolute monocyte count to clinical outcome of COVID-19 in 120 patients affected by hematological neoplasms that tested positive to SARS-CoV-2. We found that there was no statistical difference in 30-day mortality, rate of hospitalization for intensive cure and viral clearance at 14 days between fully vaccinated and unvaccinated patients. Increased 30-day mortality was associated with presence of active/progressing disease and absolute monocyte count lower than 400 cells/uL. Reduced absolute counts of monocytes should be used as an alert of increased risk of severe/critical forms of COVID-19 in patients with hematological malignancies, even when the full vaccination cycle has been completed.

Abstract

Background: Clinical course of COVID-19 depends on several patient-specific risk factors, including immune function, that is largely compromised in cancer patients. Methods: We prospectively evaluated 120 adult consecutive patients (including 34 cases of COVID-19 breakthrough after two full doses of BNT162b2 vaccine) with underlying hematological malignancies and a SARS-CoV-2 infection, in terms of patient’s clinical outcome. Results: Among fully vaccinated patients the achievement of viral clearance by day 14 was more frequent than in unvaccinated patients. Increased 30-day mortality was associated with presence of active/progressing disease and absolute monocyte count lower than 400 cells/uL. Results of multivariable analysis in unvaccinated patients showed that the pre-infection absolute count of monocytes less or equal to 400 cells/mmc, active or progressive disease of the underlying hematological malignancy, the COVID-19 severity identified by hospitalization requirement and lack of viral clearance at 14 days were independent predictors of 1-year overall survival. Conclusions: Taken together, our results indicate that absolute monocyte count determined one month before any documented SARS-CoV-2 infection could identify patients affected by hematological neoplasms with increased risk of inferior overall survival.

Seroconversion rate after vaccination against COVID-19 in patients with cancer-a systematic review

BACKGROUND

Coronavirus disease 2019 (COVID-19) has affected >210 million people worldwide. An optimal therapeutic approach for COVID-19 remains uncertain, to date. Since the history of cancer was linked to higher mortality rates due to COVID-19, the establishment of a safe and effective vaccine coverage is crucial in these patients. However, patients with cancer (PsC) were mostly excluded from vaccine candidates' clinical trials. This systematic review aims to investigate the current available evidence about the immunogenicity of COVID-19 vaccines in PsC.

PATIENTS AND METHODS

All prospective studies that evaluated the safety and efficacy of vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) were included, with immunogenicity after the first and the second dose as the primary endpoint, when available.

RESULTS

Vaccination against COVID-19 for PsC seems overall safe and immunogenic after well-conducted vaccination schedules. Yet the seroconversion rate remains lower, lagged or both compared to the general population. Patients with hematologic malignancies, especially those receiving B-cell-depleting agents in the past 12 months, are the most at risk of poor seroconversion.

CONCLUSION

A tailored approach to vaccination may be proposed to PsC, especially on the basis of the type of malignancy and of the specific oncologic treatments received.

International Association for the Study of Lung Cancer (IASLC) Study of the Impact of COVID-19 on International Lung Cancer Clinical Trials

INTRODUCTION

To evaluate the effects of the global coronavirus disease 2019 (COVID-19) pandemic on lung cancer trials, we surveyed investigators and collected aggregate enrollment data for lung cancer trials across the world before and during the pandemic.

METHODS

A Data Collection Survey collected aggregate monthly enrollment numbers from 294 global lung cancer trials for 2019 to 2020. A 64-question Action Survey evaluated the impact of COVID-19 on clinical trials and identified mitigation strategies implemented.

RESULTS

Clinical trial enrollment declined from 2019 to 2020 by 14% globally. Most reductions in enrollment occurred in April to June where we found significant decreases in individual site enrollment (p = 0.0309). Enrollment was not significantly different in October 2019 to December of 2019 versus 2020 (p = 0.25). The most frequent challenges identified by the Action Survey (N = 172) were fewer eligible patients (63%), decrease in protocol compliance (56%), and suspension of trials (54%). Patient-specific challenges included access to trial site (49%), ability to travel (54%), and willingness to visit the site (59%). The most frequent mitigation strategies included modified monitoring requirements (47%), telehealth visits (45%), modified required visits (25%), mail-order medications (25%), and laboratory (27%) and radiology (21%) tests at nonstudy facilities. Sites that felt the most effective mitigation strategies were telehealth visits (85%), remote patient-reported symptom collection (85%), off-site procedures (85%), and remote consenting (89%).

CONCLUSIONS

The COVID-19 pandemic created many challenges for lung cancer clinical trials conduct and enrollment. Mitigation strategies were used and, although the pandemic worsened, trial enrollment improved. A more flexible approach may improve enrollment and access to clinical trials, even beyond the pandemic.

Plitidepsin as a successful rescue treatment for prolonged viral SARS-CoV-2 replication in a patient with previous anti-CD20 monoclonal antibody-mediated B cell depletion and chronic lymphocytic leukemia

BACKGROUND

There is an urgent need for highly efficacious antiviral therapies in immunosuppressed hosts who develop coronavirus disease (COVID-19), with special concern for those affected by hematological malignancies.

CASE PRESENTATION

Here, we report the case of a 75-year-old male with chronic lymphocytic leukemia who was deficient in CD19⁺CD20⁺ B-lymphocyte populations due to previous treatment with anti-CD20 monoclonal antibodies. The patient presented with severe COVID-19 pneumonia due to prolonged severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and was treated with two courses of the antiviral plitidepsin on a compassionate use basis. The patient subsequently achieved an undetectable viral load, and his pneumonia resolved.

CONCLUSIONS

Treatment with plitidepsin was well-tolerated without any further hematological or cardiovascular toxicities. This case further supports plitidepsin as a potential antiviral drug in SARS-CoV-2 patients affected by immune deficiencies and hematological malignancies.

Prolonged SARS-CoV-2 infection in patients with lymphoid malignancies

Coronavirus disease 2019 (COVID-19) infection results in both acute mortality and persistent and/or recurrent disease in patients with hematologic malignancies, but the drivers of persistent infection in this population are unknown. We found that B-cell lymphomas were at particularly high risk for persistent SARS-CoV-2 positivity. Further analysis of these patients identified discrete risk factors for initial disease severity as compared to disease chronicity. Active therapy and diminished T-cell counts were drivers of acute mortality in COVID-19 infected lymphoma patients. Conversely, B-cell-depleting therapy was the primary driver of re-hospitalization for COVID-19. In patients with persistent SARS-CoV-2 positivity, we observed high levels of viral entropy consistent with intrahost viral evolution, particularly in patients with impaired CD8+ T-cell immunity. These results suggest that persistent COVID-19 infection is likely to remain a risk in patients with impaired adaptive immunity and that additional therapeutic strategies are needed to enable viral clearance in this high-risk population.

Impaired CD4 T-cell Response to SARS-CoV-2: Rationale for PD-1 Blockade in Patients with Cancer and COVID-19?

Cancer is a strong risk factor for severe COVID-19 disease. In this issue of Cancer Discovery, Bilich and colleagues demonstrate impaired preexisting and newly generated CD4 T-cell response to SARS-CoV-2 in patients with cancer.See related article by Bilich et al., p. 1982.

[Dengue amidst COVID-19: challenges & control measures for the double burden]

Dengue, an arbovirus, is a public health treat in the tropics and sub-tropical climates worldwide. The disease incidence has grown dramatically worldwide, with an estimated 390 million dengue virus infection per year. Dengue has distinct epidemiological patterns which are associated with the four virus serotypes. All four serotypes can co-circulate within a region, in which a number of regions are hyperendemic for all 4 serotypes. Currently, there are no specific treatment or vaccine for the disease. Dengue prevention depends on vector control measures and early interventions. The COVID-19 pandemic has placed immense pressure on health care and management systems worldwide. During the COVID-19 pandemic, the situation was aggravated by the simultaneous dengue outbreaks, that has led to a double burden which has further impacted the healthcare sector, particularly in resource limited settings. This review article will focus on dengue epidemics during the COVID-19 pandemic and discuss on recent findings on immunological cascades between dengue and COVID-19 and, the impact on vaccine development.