Letter: immunotherapy in IBD patients in a SARS-CoV-2 endemic area

Evaluation of infliximab/tocilizumab versus tocilizumab among COVID-19 patients with cytokine storm syndrome

Coronavirus Disease 2019 (COVID-19) continues to spread rapidly. Monoclonal antibodies as well as anti-tumor necrosis factor are considered promising treatments for COVID-19. A prospective cohort study in which patients are divided into three groups. Group 1: moderate and severe COVID-19 patients received standard treatment; Group 2: moderate and severe COVID-19 patients received tocilizumab; Group 3: moderate and severe COVID-19 patients received treatment with infliximab and tocilizumab. 153 patients were recruited in the study. 40 received standard treatment alone, 70 received tocilizumab with standard treatment, and 43 received tocilizumab/infliximab with standard treatment. There was a significant difference in length of hospital stay (10.3, 8.9, and 7.6 days respectively P = 0.03), need for a non-invasive mechanical ventilator (4, 5, and one patient; P = 1.2E-8), intensive care admission (32, 45, and 16 patients; P = 2.5E-5), the occurrence of sepsis (18, 12, and 10 patients; P = 0.005) and in death (42.5%, 14.2%, and 7%; P = 0.0008) which were significantly lower in tocilizumab/infliximab group compared to tocilizumab and standard of care groups. Our study showed that tocilizumab/ infliximab in addition to standard of care was considered a promising treatment for moderate and severe COVID-19 patients.Trial registration number: ClinicalTrials.gov NCT04734678; date of registration: 02/02/2021.

Impact of Immunotherapies on SARS-CoV-2-Infections and Other Respiratory Tract Infections during the COVID-19 Winter Season in IBD Patients

Background

COVID-19 represents one of the most significant medical problems of our time.

Aims

This study is focused on the question whether patients with inflammatory bowel disease (IBD) who receive immunotherapies are more vulnerable to respiratory tract infections and SARS-CoV-2 infections in comparison to medical staff, as a cohort with an increased infection risk, and to the general population in a COVID-19 hotspot.

Methods

We analysed data regarding respiratory tract infections that were collected in our IBD registry and compared them with corresponding data from medical employees in our associated Isarklinikum hospital and from the healthy general population in Munich, Germany, over the same time frame in April and June 2020. Patients were tested for SARS-CoV-2 immunoglobulins (Ig).

Results

Symptoms of respiratory tract infections occurred equally frequent in IBD patients with immunotherapies as compared to those without. Older age (>49 years), TNF-inhibitor, and ustekinumab treatment showed a significantly protective role in preventing respiratory tract symptomatic COVID-19 infections that occurred in 0.45% of all our 1.091 IBD patients. Of those, 1.8% were positive for SARS-CoV-2 Ig, identically to the general population of Munich with also 1.8% positivity. Whilst more than 3% of all COVID-19 subjects of the general population died during the first wave, none of our IBD patients died or needed referral to the ICU or oxygen treatment.

Conclusions

In our study, IBD patients are as susceptible to respiratory tract infections or SARS-CoV-2 as the normal population. There is no evidence of an association between IBD therapies and increased risk of COVID-19. Interestingly, a reduced rate of COVID-19 deaths in IBD patients, the majority on immunomodulator therapy, was observed, compared to the general population. Therefore, no evidence was found to suggest that IBD medication should be withheld, and adherence should be encouraged to prevent flares. In addition to older age (>49 years), TNF inhibitors and ustekinumab show a protective role in preventing respiratory tract infections. In addition, these results add to the growing evidence that supports further investigation of TNF inhibitors as a possible treatment in the early course of severe COVID-19.

COVID-19 and Outcomes in Patients With Inflammatory Bowel Disease: Systematic Review and Meta-Analysis

BACKGROUND

Our understanding of coronavirus disease 2019 (COVID-19) and its implications for patients with inflammatory bowel diseases (IBD) is rapidly evolving. We performed a systematic review and meta-analysis to investigate the epidemiology, clinical characteristics, and outcomes in IBD patients with COVID-19.

METHODS

We searched PubMed, EMBASE, Cochrane Central, Clinicaltrials.gov, Web of Science, MedRxiv, and Google Scholar from inception through October 2020. We included studies with IBD patients and confirmed COVID-19. Data were collected on the prevalence, patient characteristics, pre-infection treatments for IBD, comorbidities, hospitalization, intensive care unit (ICU), admission, and death.

RESULTS

Twenty-three studies with 51,643 IBD patients and 1449 with COVID-19 met our inclusion criteria. In 14 studies (n = 50,706) that included IBD patients with and without COVID-19, the prevalence of infection was 1.01% (95% confidence interval [CI], 0.92-1.10). Of IBD patients with COVID-19, 52.7% had Crohn's disease, 42.2% had ulcerative colitis, and 5.1% had indeterminate colitis. Nine studies (n = 687) reported outcomes according to IBD therapy received. Compared with patients on corticosteroids, those on antitumor necrosis factor (anti-TNF) therapy had a lower risk of hospitalization (risk ratio [RR], 0.24; 95% CI, 0.16-0.35; P < .01; I2 = 0%) and ICU admission (RR, 0.10; 95% CI, 0.03-0.37; P < .01) but not death (RR, 0.16; 95% CI, 0.02-1.71; P = .13; I2 = 39%). Compared with patients on mesalamine, those on antitumor necrosis factor therapy had a lower risk of hospitalizations (RR, 0.37; 95% CI, 0.25-0.54), ICU admissions (RR, 0.20; 95% CI, 0.07-0.58), and death (0.21; 95% CI, 0.04-1.00). Comparing patients on immunomodulators vs mesalamine or anti-TNF therapy, there was no difference in these outcomes.

CONCLUSIONS

The prevalence of COVID-19 in IBD patients was low. Use of corticosteroids or mesalamine was significantly associated with worse outcomes, whereas use of anti-TNFs was associated with more favorable outcomes. Further investigation clarifying the mechanisms of these disparate observations could help identify risk and adverse outcome-mitigating strategies for patients with IBD.

Application of Monoclonal Antibody Drugs in Treatment of COVID-19: a Review

Coronavirus infection can have various degrees of severity and outcomes. In some cases, it causes excessive production of pro-inflammatory cytokines, a so-called cytokine storm, leading to acute respiratory distress syndrome. Unfortunately, the exact pathophysiology and treatment, especially for severe cases of COVID-19, are still uncertain. Results of preliminary studies showed that immunosuppressive therapy, such as interleukin (IL)-6, IL-1, and TNF-α antagonists commonly used in rheumatology, can be considered as treatment options for COVID-19, especially in severe cases. The review focused on the most common and currently studied monoclonal antibody drugs, as well as up-to-date data on the pathogenesis of COVID-19, host immune response against SARS-CoV-2 and its association with cytokine storm. It also covered effects of interleukin (IL)-6, IL-1, and TNF-α blockers on the course of coronavirus infection and outcome in patients treated for the main autoimmune disease and subsequently infected with COVID-19.

Identification of serum metabolites enhancing inflammatory responses in COVID-19

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is characterized by a strong production of inflammatory cytokines such as TNF and IL-6, which underlie the severity of the disease. However, the molecular mechanisms responsible for such a strong immune response remains unclear. Here, utilizing targeted tandem mass spectrometry to analyze serum metabolome and lipidome in COVID-19 patients at different temporal stages, we identified that 611 metabolites (of 1,039) were significantly altered in COVID-19 patients. Among them, two metabolites, agmatine and putrescine, were prominently elevated in the serum of patients; and 2-quinolinecarboxylate was changed in a biphasic manner, elevated during early COVID-19 infection but levelled off. When tested in mouse embryonic fibroblasts (MEFs) and macrophages, these 3 metabolites were found to activate the NF-κB pathway that plays a pivotal role in governing cytokine production. Importantly, these metabolites were each able to cause strong increase of TNF and IL-6 levels when administered to wildtype mice, but not in the mice lacking NF-κB. Intriguingly, these metabolites have little effects on the activation of interferon regulatory factors (IRFs) for the production of type I interferons (IFNs) for antiviral defenses. These data suggest that circulating metabolites resulting from COVID-19 infection may act as effectors to elicit the peculiar systemic inflammatory responses, exhibiting severely strong proinflammatory cytokine production with limited induction of the interferons. Our study may provide a rationale for development of drugs to alleviate inflammation in COVID-19 patients.

Systematic review with meta-analysis: COVID-19 outcomes in patients receiving anti-TNF treatments

BACKGROUND

Accumulating evidence suggests a beneficial effective of tumour necrosis factor-alpha (TNF-α) inhibitors on the outcomes of COVID-19 disease, which, however is not validated by all studies.

AIMS

To perform a systematic review and meta-analysis of existing reports to investigate the impact of anti-TNF treatments on the clinical outcomes of COVID-19 patients.

METHODS

A systematic search at PubMed and SCOPUS databases using specific keywords was performed. All reports of COVID-19 outcomes for patients receiving anti-TNF therapy by September 2021 were included. Pooled effect measures were calculated using a random-effects model. The Newcastle Ottawa Scale for observational studies was used to assess bias. Studies that were not eligible for meta-analysis were described qualitatively.

RESULTS

In total, 84 studies were included in the systematic review, and 35 were included in the meta-analysis. Patients receiving anti-TNF treatment, compared to non-anti-TNF, among COVID-19 cases had a lower probability of hospitalisation (eight studies, 2555 patients, pooled OR = 0.53, 95% CI: 0.42-0.67, I2  = 0) and severe disease defined as intensive care unit admission or death (two studies, 1823 patients, pooled OR = 0.63, 95% CI: 0.41-0.96, I2  = 0), after adjustment for validated predictors of adverse disease outcomes. No difference was found for the risk for hospitalisation due to COVID-19 in populations without COVID-19 for patients receiving anti-TNF treatment compared to non-anti-TNF (three studies, 5 994 958 participants, pooled risk ratio = 0.97, 95% CI: 0.68-1.39, I2  = 20) adjusted for age, sex and comorbidities.

CONCLUSIONS

TNF-α inhibitors are associated with a lower probability of hospitalisation and severe COVID-19 when compared to any other treatment for an underlying inflammatory disease.

The 'cytokine storm': molecular mechanisms and therapeutic prospects

Cytokine storm syndrome (CSS) has generally been described as a collection of clinical manifestations resulting from an overactivated immune system. Cytokine storms (CSs) are associated with various pathologies, as observed in infectious diseases, certain acquired or inherited immunodeficiencies and autoinflammatory diseases, or following therapeutic interventions. Despite the role of CS in tissue damage and multiorgan failure, a systematic understanding of its underlying molecular mechanisms is lacking. Recent studies demonstrate a positive feedback loop between cytokine release and cell death pathways; certain cytokines, pathogen-associated molecular patterns (PAMPs), and damage-associated molecular patterns (DAMPs), can activate inflammatory cell death, leading to further cytokine secretion. Here, we discuss recent progress in innate immunity and inflammatory cell death, providing insights into the cellular and molecular mechanisms of CSs and therapeutics that might quell ensuing life-threatening effects.

The Potential for Repurposing Anti-TNF as a Therapy for the Treatment of COVID-19

Coronavirus disease 2019 (COVID-19) currently has few effective treatments. Given the uncertainty surrounding the effectiveness and uptake of a vaccine, it is important that the search for treatments continue. An exaggerated inflammatory state is likely responsible for much of the morbidity and mortality in COVID-19. Elevated levels of tumor necrosis factor (TNF), a key pro-inflammatory cytokine, have been shown to be associated with increased COVID-19 mortality. In patients with rheumatoid arthritis, TNF blockade reduces not only biologically active TNF but other pro-inflammatory cytokines important in COVID-19 hyperinflammation. Observational data from patients already on anti-TNF therapy show a reduced rate of COVID-19 poor outcomes and death compared with other immune-suppressing therapies. Anti-TNF has a long history of safe use, including in special at-risk populations, and is widely available. The case to adequately assess anti-TNF as a treatment for COVID-19 is compelling.

Synergism of TNF-α and IFN-γ Triggers Inflammatory Cell Death, Tissue Damage, and Mortality in SARS-CoV-2 Infection and Cytokine Shock Syndromes

COVID-19 is characterized by excessive production of pro-inflammatory cytokines and acute lung damage associated with patient mortality. While multiple inflammatory cytokines are produced by innate immune cells during SARS-CoV-2 infection, we found that only the combination of TNF-α and IFN-γ induced inflammatory cell death characterized by inflammatory cell death, PANoptosis. Mechanistically, TNF-α and IFN-γ co-treatment activated the JAK/STAT1/IRF1 axis, inducing nitric oxide production and driving caspase-8/FADD-mediated PANoptosis. TNF-α and IFN-γ caused a lethal cytokine shock in mice that mirrors the tissue damage and inflammation of COVID-19, and inhibiting PANoptosis protected mice from this pathology and death. Furthermore, treating with neutralizing antibodies against TNF-α and IFN-γ protected mice from mortality during SARS-CoV-2 infection, sepsis, hemophagocytic lymphohistiocytosis, and cytokine shock. Collectively, our findings suggest that blocking the cytokine-mediated inflammatory cell death signaling pathway identified here may benefit patients with COVID-19 or other infectious and autoinflammatory diseases by limiting tissue damage/inflammation.

Synergism of TNF-α and IFN-γ triggers inflammatory cell death, tissue damage, and mortality in SARS-CoV-2 infection and cytokine shock syndromes

The COVID-19 pandemic has caused significant morbidity and mortality. Currently, there is a critical shortage of proven treatment options and an urgent need to understand the pathogenesis of multi-organ failure and lung damage. Cytokine storm is associated with severe inflammation and organ damage during COVID-19. However, a detailed molecular pathway defining this cytokine storm is lacking, and gaining mechanistic understanding of how SARS-CoV-2 elicits a hyperactive inflammatory response is critical to develop effective therapeutics. Of the multiple inflammatory cytokines produced by innate immune cells during SARS-CoV-2 infection, we found that the combined production of TNF-α and IFN-γ specifically induced inflammatory cell death, PANoptosis, characterized by gasdermin-mediated pyroptosis, caspase-8-mediated apoptosis, and MLKL-mediated necroptosis. Deletion of pyroptosis, apoptosis, or necroptosis mediators individually was not sufficient to protect against cell death. However, cells deficient in both RIPK3 and caspase-8 or RIPK3 and FADD were resistant to this cell death. Mechanistically, the JAK/STAT1/IRF1 axis activated by TNF-α and IFN-γ co-treatment induced iNOS for the production of nitric oxide. Pharmacological and genetic deletion of this pathway inhibited pyroptosis, apoptosis, and necroptosis in macrophages. Moreover, inhibition of PANoptosis protected mice from TNF-α and IFN-γ-induced lethal cytokine shock that mirrors the pathological symptoms of COVID-19. In vivo neutralization of both TNF-α and IFN-γ in multiple disease models associated with cytokine storm showed that this treatment provided substantial protection against not only SARS-CoV-2 infection, but also sepsis, hemophagocytic lymphohistiocytosis, and cytokine shock models, demonstrating the broad physiological relevance of this mechanism. Collectively, our findings suggest that blocking the cytokine-mediated inflammatory cell death signaling pathway identified here may benefit patients with COVID-19 or other cytokine storm-driven syndromes by limiting inflammation and tissue damage. The findings also provide a molecular and mechanistic description for the term cytokine storm. Additionally, these results open new avenues for the treatment of other infectious and autoinflammatory diseases and cancers where TNF-α and IFN-γ synergism play key pathological roles.

Letter: immunotherapy for IBD patients in a SARS-CoV-2 endemic area-authors' reply

LINKED CONTENT

This article is linked to Taxonera et al and Szokodi papers. To view these articles, visit https://doi.org/10.1111/apt.15804 and https://doi.org/10.1111/apt.15897