Adverse reactions to Janus kinase inhibitors: Study of their incidence and predictive factors in patients with rheumatoid arthritis

BACKGROUND AND OBJECTIVE

The safety profile of Janus Kinase (JAK) inhibitors has acquired attention due to post-marketing observed adverse drug reactions. The study focuses on the analysis of adverse reactions related to tofacitinib, baricitinib, upadacitinib, and filgotinib in rheumatoid arthritis patients, including identifying predictive factors linked to their occurrence.

PATIENTS AND METHODS

Observational retrospective study. Adult patients with rheumatoid arthritis from a university hospital receiving JAK inhibitor treatment between September 2017 and January 2024 were included. The cumulative incidence of each adverse reaction was calculated using the Naranjo scale. Risk factors for developing adverse reactions were identified through logistic regression analyses.

RESULTS

Two hundred twenty-three patients were included, with 28.7% presenting adverse reaction related to JAK inhibitor treatment. The adverse drug reactions with the highest cumulative incidence were infections and gastrointestinal disorders. Infections included: upper respiratory tract (4.5%), cellulitis (3.1%), urinary tract (2.7%), herpes zoster (1.8%). Gastrointestinal disorders comprised: abdominal pain (4.0%), diarrhea (3.6%), nausea and vomiting (3.6%), gastrointestinal perforation (1.3%), diverticulitis (0.9%). Classified at 0.5% were: headache, paresthesias, skin rash, severe neutropenia, insomnia, dyspnea, hypertensive crisis. As risk factors, were identified: the treatment with a non-selective JAK inhibitor (OR adjusted: 4.03; 95% CI: 1.15-14.10; P=.029) and older age (OR adjusted: 1.03; 95% CI: 1.00-1.05; P=.036).

CONCLUSIONS

Infections and gastrointestinal disorders represented the adverse reactions related to JAK inhibitor treatment with the highest cumulative incidence, with risk factors for their occurrence being non-selective JAK inhibitor treatment and older age of the patient.

Kinetics of IFNγ-Induced Cytokines and Development of Immune-Related Adverse Events in Patients Receiving PD-(L)1 Inhibitors

Immune checkpoint inhibitors (ICI) have the potential to trigger unpredictable immune-related adverse events (irAEs), which can be severe. The underlying mechanisms of these events are not fully understood. As PD-L1 is upregulated by IFN, the heightened immune activation resulting from PD-1/PD-L1 inhibition may enhance the IFN response, triggering the expression of IFN-inducible genes and contributing to irAE development and its severity. In this study, we investigated the interplay between irAEs and the expression of IFN-inducible chemokines and cytokines in 134 consecutive patients with solid tumours treated with PD-(L)1 inhibitors as monotherapy or in combination with chemotherapy or other immunotherapy agents. We compared the plasma levels of IFN-associated cytokines (CXCL9/10/11, IL-18, IL-10, IL-6 and TGFβ) at various time points (at baseline, at the onset of irAE and previous to irAE onset) in three patient groups categorized by irAE development and severity: patients with serious irAEs, mild irAEs and without irAEs after PD-(L)1 inhibitors. No differences were observed between groups at baseline. However, patients with serious irAEs exhibited significant increases in CXCL9/10/11, IL-18 and IL-10 levels at the onset of the irAE compared to baseline. A network analysis and correlation patterns highlighted a robust relationship among these chemokines and cytokines at serious-irAE onset. Combining all of the analysed proteins in a cluster analysis, we identified a subgroup of patients with a higher incidence of serious irAEs affecting different organs or systems. Finally, an ROC analysis and a decision tree model proposed IL-18 levels ≥ 807 pg/mL and TGFβ levels ≤ 114 pg/mL as predictors for serious irAEs in 90% of cases. In conclusion, our study elucidates the dynamic changes in cytokine profiles associated with serious irAE development during treatment with PD-(L)1 inhibitors. The study's findings offer valuable insights into the intricate IFN-induced immune responses associated with irAEs and propose potential predictive markers for their severity.

Levels of Lysozyme and SLPI in Bronchoalveolar Lavage: Exploring Their Role in Interstitial Lung Disease

Interstitial lung diseases (ILDs) are characterized by inflammation or fibrosis of the pulmonary parenchyma. Despite the involvement of immune cells and soluble mediators in pulmonary fibrosis, the influence of antimicrobial peptides (AMPs) remains underexplored. These effector molecules display a range of activities, which include immunomodulation and wound repair. Here, we investigate the role of AMPs in the development of fibrosis in ILD. We compare the concentration of different AMPs and different cytokines in 46 fibrotic (F-ILD) and 17 non-fibrotic (NF-ILD) patients by ELISA and using peripheral blood mononuclear cells from in vitro stimulation in the presence of lysozyme or secretory leukocyte protease inhibitor (SLPI) from 10 healthy donors. We observed that bronchoalveolar lavage (BAL) levels of AMPs were decreased in F-ILD patients (lysozyme: p < 0.001; SLPI: p < 0.001; LL-37: p < 0.001; lactoferrin: p = 0.47) and were negatively correlated with levels of TGF-β (lysozyme: p = 0.02; SLPI: p < 0.001) and IL-17 (lysozyme: p < 0.001; SLPI: p < 0.001). We observed that lysozyme increased the percentage of CD86+ macrophages (p < 0.001) and the production of TNF-α (p < 0.001). We showed that lysozyme and SLPI were associated with clinical parameters (lysozyme: p < 0.001; SLPI: p < 0.001) and disease progression (lysozyme: p < 0.001; SLPI: p = 0.01). These results suggest that AMPs may play an important role in the anti-fibrotic response, regulating the effect of pro-fibrotic cytokines. In addition, levels of lysozyme in BAL may be a potential biomarker to predict the progression in F-ILD patients.

Influence of Malignant Pleural Fluid from Lung Adenocarcinoma Patients on Neutrophil Response

Malignant pleural effusion (MPE) is a common severe complication of advanced lung adenocarcinoma (LAC). Neutrophils, an essential component of tumor infiltrates, contribute to tumor progression and their counts in MPE have been associated with worse outcome in LAC. This study aimed to evaluate phenotypical and functional changes of neutrophils induced by MPE to determine the influence of MPE immunomodulatory factors in neutrophil response and to find a possible association between neutrophil functions and clinical outcomes. Pleural fluid samples were collected from 47 LAC and 25 heart failure (HF) patients. We measured neutrophil degranulation products by ELISA, oxidative burst capacity and apoptosis by flow cytometry, and NETosis by fluorescence. The concentration of degranulation products was higher in MPE-LAC than in PE-HF. Functionally, neutrophils cultured with MPE-LAC had enhanced survival and neutrophil extracellular trap (NET) formation but had reduced oxidative burst capacity. In MPE, NETosis was positively associated with MMP-9, P-selectin, and sPD-L1 and clinically related to a worse outcome. This is the first study associating NETs with a worse outcome in MPE. Neutrophils likely contribute to tumor progression through the release of NETs, suggesting that they are a potential therapeutic target in LAC.

Are There Sex-Related Differences in the Effectiveness of Janus Kinase Inhibitors in Rheumatoid Arthritis Patients?

Background: There is evidence suggesting the existence of sex differences in the effectiveness of specific drug classes for rheumatoid arthritis (RA). Our study stands as the first to elucidate sex-related differences in the effectiveness of Janus kinase (JAK) inhibitors. Methods: The study involved 150 RA patients treated with tofacitinib, baricitinib, upadacitinib, or filgotinib between September 2017 and October 2023. Sex differences in achieving remission and low disease activity (LDA) were identified through logistic regression analyses. Sex disparities in treatment effectiveness survival were evaluated through the Kaplan-Meier estimate, employing the log-rank test for comparison. The Cox model was applied to analyze the variable sex as a potential factor that could influence the maintenance of the JAK inhibitor treatment effectiveness. Results: Concerning the achievement of remission and LDA, no differences were observed between sexes in terms of the 28-joint Disease Activity Score (DAS28) C-reactive protein (CRP), the Clinical Disease Activity Index (CDAI), and the Simplified Disease Activity Index (SDAI). With respect to the DAS28-erythrocyte sedimentation rate (ESR), female patients, compared to males, possessed 70% lower odds of achieving remission (p = 0.018) and 66% lower odds of achieving LDA (p = 0.023). No differences were observed in treatment effectiveness survival between sexes (p = 0.703). Sex was not found to influence the survival of JAK inhibitor treatment effectiveness (p = 0.704). Conclusions: Being a female or male patient does not entail differences in the effectiveness of the JAK inhibitor treatment. Our findings encourage the consideration of a global pool of composite indices (DAS28-ESR/CRP, CDAI, SDAI) to measure RA disease activity, thus individualizing the target value as advocated by the treat-to-target strategy.

Sequence of the HLA-B*1573 allele

We report here the sequence of an HLA B*15 allele, B*1573. Initially, a cord blood unit from the Umbilical Cord Bank of Barcelona was typed by sequence-specific oligonucleotide hybridization and revealed an unusual hybridization pattern. After the cloning, the sequence-based typing assigned two different alleles: B*07021, and a second allele identical to B*1558 in exons 2 and 3, except for a single nucleotide substitution in exon 3, which changed codon 140 from Phe to Leu (TTX-->TTA).

Experimental supporting data on the influence of platelet-derived factors of malignant pleural effusions on T cell effector functions and their relevance in predicting prognosis of lung adenocarcinoma patients with pleural metastasis

The data described in this article are supplementary to our primary article "Platelet factor 4 regulates T cell effector functions in malignant pleural effusions". Malignant pleural effusion (MPE) is a common complication of advanced lung adenocarcinoma (LAC) associated with a poor life expectancy [1]. Several challenges need to be addressed to identify non-invasive molecular biomarkers that help to predict the prognosis of LAC patients with MPE [2]. In the primary publication, we proposed that platelet-derived factors, especially platelet factor 4 (PF4), can negatively regulate T lymphocyte activation and granzyme B expression in pleural metastasis and its levels were associated with a worse prognosis. Here, we provide data on the influence of other platelet-derived factors, including transforming growth factor β (TGF-β), vascular endothelial factor (VEGF), and P-selectin on T lymphocyte response in MPE and their relevance as prognostic factors in lung cancer patients with pleural metastasis. Pleural fluids from 35 lung adenocarcinoma (LAC) and 20 heart failure (HF) patients were collected by thoracentesis and its platelet-derived factors' content was measured by specific enzyme-linked immunosorbent assay (ELISAs). Correlations between pleural levels of platelet-derived factors and T cell functions were analyzed by Pearson coefficients. Kaplan-Meier curves were used to estimate the effect of pleural concentrations of platelet-derived factors on overall survival of LAC patients with pleural metastasis. These analyses showed that the concentration of platelet-derived factors was not associated with T cell proliferation and cytotoxicity. Furthermore, their levels do not predict the survival of LAC with MPE.

Corrigendum: Patients with myeloproliferative neoplasms harbor high frequencies of CD8 T cell-platelet aggregates associated with T cell suppression

[This corrects the article DOI: 10.3389/fimmu.2022.866610.].

Clinical Relevance of Tumour-Infiltrating Immune Cells in HER2-Negative Breast Cancer Treated with Neoadjuvant Therapy

Currently, therapy response cannot be accurately predicted in HER2-negative breast cancer (BC). Measuring stromal tumour-infiltrating lymphocytes (sTILs) and mediators of the tumour microenvironment and characterizing tumour-infiltrating immune cells (TIICs) may improve treatment response in the neoadjuvant setting. Tumour tissue and peripheral blood samples were retrospectively collected from 118 patients, and sTILs were evaluated. Circulating exosomes and myeloid-derived suppressor cells were determined by flow cytometry. TIICs markers (CD4, CD8, CD20, CD1a, and CD68) were assessed immunohistochemically. High sTILs were significantly associated with pathological complete response (pCR; p = 0.048) and event-free survival (EFS; p = 0.027). High-CD68 cells were significantly associated with pCR in triple-negative (TN, p = 0.027) and high-CD1a cells with EFS in luminal-B (p = 0.012) BC. Cluster analyses of TIICs revealed two groups of tumours (C1 and C2) that had different immune patterns and clinical outcomes. An immunoscore based on clinicopathological variables was developed to identify high risk (C1) or low-risk (C2) patients. Additionally, cluster analyses revealed two groups of tumours for both luminal-B and TNBC. Our findings support the association of sTILs with pCR and show an immunological component in a subset of patients with HER2-negative BC. Our immunoscore may be useful for future escalation or de-escalation treatments.

The role of BALB/c donor CD8+ lymphocytes in graft-versus-host disease in (BALB/c x A/J)F1 (CAF1) mice

To investigate the role of donor T lymphocyte subsets in the development of chronic graft-vs-host disease (GVHD) induced in (BALB/c x A/J)F1 (CAF1) mice by injecting BALB/c lymphoid cells, we analyzed the effect that CD8+ cell removal from donor inoculum has on the manifestation of the disease. Compared with age- and sex-matched CAF1 mice injected with whole lymphocyte inoculum, CAF1 mice injected with CD8(+)-depleted inoculum exhibited: 1) a higher incidence and exacerbation of nephritis by immunocomplexes; 2) higher (five- to sevenfold) spontaneous IL-4 production; 3) higher frequency titer and precocity of anti-dsDNA, anti-histone, and IgM and IgG rheumatoid factors; 4) a dramatic change in the frequency and titer of anti-U1 small nuclear ribonucleoprotein Abs; and 5) a markedly decreased engraftment (10- to 15-fold) on BALB/c donor lymphocytes. In contrast, rheumatoid arthritis-like disease, a later clinical manifestation of the GVHD in CAF1 + BALB/c model, is not present in the CD8(+)-depleted model (CAF1 + CD8-BALB/c). Considered together, these data suggest that CD8+ donor T lymphocytes play an important role in the degree of chimerism, modulation of the response to autoantigens, and clinical aspects developed in the GVHD model presented here.

Correction: Vidal et al. From Messengers to Receptors in Psoriasis: The Role of IL-17RA in Disease and Treatment. Int. J. Mol. Sci. 2021, 22, 6740

In the original publication [...].

Biomarkers of Frailty in Patients with Advanced Chronic Liver Disease Undergoing a Multifactorial Intervention Consisting of Home Exercise, Branched-Chain Amino Acids, and Probiotics

Frailty in cirrhosis or advanced chronic liver disease (ACLD) is a relevant prognostic factor. In the present study, we aimed to analyze potential biomarkers associated with frailty and its improvement in patients with ACLD. We analyzed the serum of outpatients with ACLD who participated in a previous study (Román, Hepatol Commun 2024) in which frailty was assessed using the liver frailty index (LFI), and patients who were frail or prefrail were randomized to a multifactorial intervention (home exercise, branched-chain amino acids, and probiotics) or control for 12 months. We determined a biomarker battery of inflammation, bacterial translocation, and liver damage in blood and urine and blood metabolomics by 1H-NMR. Thirty-seven patients were included. According to the LFI, 32 patients were frail or prefrail, and 5 were robust. At baseline, LFI correlated with LBP, sCD163, mtDNA, FGF-21, urinary NGAL, urinary claudin-3, and the metabolites mannose, ethanol, and isoleucine. During the study, patients in the intervention group showed an improvement in LFI and a decrease in CRP, LBP, sCD163, and ccK18 compared to the control group. Metabolomics showed a decrease in dimethyl sulfone and creatinine and an increase in malonate, ornithine, isoleucine, and valine in the intervention group. We conclude that frailty in patients with ACLD is associated with biomarkers of systemic inflammation, bacterial translocation, and liver damage, and alterations of amino acid and short-chain fatty acid metabolism.

Home exercise, branched-chain amino acids, and probiotics improve frailty in cirrhosis: A randomized clinical trial

BACKGROUND

Frailty is a predictive factor of hospitalization, falls, and mortality in patients with cirrhosis, regardless of the degree of liver failure. The aim was to analyze whether a multifactorial intervention consisting of home-based exercise, branched-chain amino acids, and a multistrain probiotic can improve frailty in these patients.

METHODS

Outpatients with cirrhosis were classified according to the Liver Frailty Index (LFI). Prefrail and frail patients were randomized into 2 groups. The intervention group was assigned to a multifactorial intervention consisting of exercise at home, branched-chain amino acid supplements, and a multistrain probiotic for 12 months. The control group received standard care. All patients were prospectively followed up every 3 months for 1 year to determine LFI, incidence of falls, emergency room visits, hospitalizations, and mortality.

RESULTS

Thirty-two patients were included: 17 patients were assigned to the intervention group and 15 to the control group. In the intervention group, the baseline LFI decreased at 3, 6, 9, and 12 months (p = 0.019 for overall change with respect to the control group). The change in LFI (ΔLFI) at 12 months was -0.71 ± 0.24 in the intervention group and -0.09 ± 0.32 in the control group (p<0.001). During follow-up, patients in the intervention group had a lower 1-year probability of falls (6% vs. 47%, p = 0.03) and emergency room visits (10% vs. 44%, p = 0.04) than patients in the control group.

CONCLUSIONS

A long-term multifactorial intervention that included exercise at home, branched-chain amino acids, and a multistrain probiotic improved frailty in outpatients with cirrhosis and was associated with a decrease in the incidence of clinical events such as falls and emergency room visits.

Interplay of leucocyte-platelet complexes and clinical response to eltrombopag in immune thrombocytopenia patients

Eltrombopag (ELT) is a thrombopoietin-receptor agonist that stimulates platelet (PLT) production in patients with primary immune thrombocytopenia (ITP). One potential mechanism of ELT is modulating the inflammatory response by increasing PLTs binding to leucocytes. This study examined the effect of ELT on leucocyte-PLTs complexes in 38 ITP patients. Patients, predominantly females with a mean age of 59 years, underwent treatments like corticosteroids, intravenous immunoglobulin and splenectomy. Compared to healthy donors, ITP patients exhibited lower percentages of lymphocyte with bound PLTs, but similar monocyte- or neutrophil with bound PLTs. ELT treatment increased PLTs counts and all types of leucocyte with bound PLTs. Network analysis showed dynamic changes in leucocyte with bound PLTs relationships due to ELT. Machine learning indicated that higher percentages of monocytes with bound PLTs were linked to a better clinical response to ELT. A possible mechanism was an increased IL-10 production in monocytes with bound PLTs from responder patients. This study provides insights into the immunological changes in ITP patients undergoing ELT and suggests potential predictive biomarkers for treatment response and disease monitoring.

Autoantibodies to a transfer RNA-associated protein in a murine model of chronic graft versus host disease

We established chronic graft vs host disease (GVHD) in (C57BL/10 x DBA/2)F1 mice with an injection of lymphoid cells from the parental DBA/2 strain. In addition to Abs earlier reported, of the 20 animals studied 13 developed Abs against transfer RNA/protein particles. Ten of the 13 sera immunoprecipitated a similar-sized RNA that co-migrated in PAGE with isoleucine tRNA. In immunoblots against proteins affinity purified using anti-isoleucyl-tRNA synthetase prototype serum, 7 of the 10 sera reacted with a polypeptide of 76 kDa that was similar in size to a protein recognized by a human anti-isoleucyl-tRNA synthetase serum. Three of 10 sera significantly and specifically inhibited isoleucyl-tRNA synthetase enzyme activity and one inhibited lysyl-tRNA synthetase activity. These data suggest that the autoantibodies to tRNA-associated proteins that develop in GVHD mice may react with amino acyl-tRNA synthetases, particularly those belonging to the multienzyme complex. Such autoantibodies are associated with myositis in humans, and these mice showed evidence compatible with myositis that appeared to be a manifestation of their GVHD. No previous example of spontaneous development of antisynthetases in animals has been described. We also demonstrated the presence of Abs against the NOR:90 nucleolar Ag as a new target in chronic GVHD. We conclude that chronic GVHD in mice provides a model for the study of the autoimmune responses that characterize human diseases such as mixed connective tissue disease, scleroderma, SLE, and myositis with a wider autoantibody response than that described so far.

Interindividual variability and its impact on the effectiveness of Janus kinase inhibitors in rheumatoid arthritis treatment

INTRODUCTION

Achieving the primary treat-to-target (T2T) goal in rheumatoid arthritis (RA) remains challenging for many patients, reflecting limitations in the effectiveness of existing treatments. Our study examines factors influencing Janus kinase (JAK) inhibitor effectiveness by analyzing interindividual variability in demographic and clinical characteristics of real-world RA patients.

MATERIALS AND METHODS

This observational retrospective study involves RA patients receiving tofacitinib, baricitinib, upadacitinib, or filgotinib between September 2017 and January 2025. Predictive factors of achieving the T2T goal at 6 months were identified through logistic regression analyses. Disparities in the treatment effectiveness retention based on predictive factors were assessed using the Kaplan-Meier estimate and compared with the log-rank test. The Cox model was applied to analyze whether the predictive factors identified could influence the retention of JAK inhibitor treatment effectiveness.

RESULTS

One hundred fifty patients were included: 81 (54%) achievers and 69 (46%) non-achievers of remission or, at least, low disease activity at 6 months of treatment. High disease activity at baseline, with respect to moderate activity, was identified as an unfavorable factor for achieving the T2T goal (Odds ratio adjusted: 0.96; 95% confidence interval: 0.92-0.99; p = 0.028). In treatment effectiveness retention rates, no differences were observed between patients with high versus moderate disease activity (p = 0.103). RA disease activity at baseline was not found to impact the survival of JAK inhibitor effectiveness (p = 0.106).

CONCLUSION

In RA, high disease activity at the initiation of treatment with tofacitinib, baricitinib, upadacitinib, or filgotinib does not preclude an effective treatment response but is associated with an increased risk of therapeutic failure. Factors not related to the achievement of the T2T goal at 6 months of JAK inhibitor treatment include: age, female sex, body mass index, RA disease duration, seropositivity for rheumatoid factor, seropositivity for anti-cyclic citrullinated peptides, JAK inhibitor selectivity, type and number of prior biologic treatments, concomitant use and number of prior conventional synthetic disease-modifying antirheumatic drugs, and number of prior JAK inhibitors. These conclusions are derived from a retrospective real-world study and should be confirmed in prospective studies.

Proceedings of the 5th Meeting of Translational Hepatology, organized by the Spanish Association for the Study of the Liver (AEEH)

This is the summary report of the 5th Translational Hepatology Meeting, endorsed by the Spanish Association for the Study of the Liver (AEEH) and held in Seville, Spain, in October 2023. The meeting aimed to provide an update on the latest advances in the field of basic and translational hepatology, covering different molecular, cellular, and pathophysiological aspects of the most relevant clinical challenges in liver pathologies. This includes the identification of novel biomarkers and diagnostic tools, the understanding of the relevance of immune response and inflammation in liver diseases, the characterization of current medical approaches to reverse liver diseases, the incorporation of novel molecular insights through omics techniques, or the characterization of the impact of toxic and metabolic insults, as well as other organ crosstalk, in liver pathophysiology.

Association between the Immunophenotype of Peripheral Blood from mCRPC Patients and the Outcomes of Radium-223 Treatment

(1) Background: Prostate cancer is the second most common cancer in men, with androgen suppression as the standard treatment. Despite initially responding to castration, most metastatic prostate cancer patients eventually experience progression. In these cases, Radium-223 is the chosen treatment. We hypothesized that the immunophenotype of circulating leukocytes conditions the response to Radium-223 treatment. (2) Material and Methods: In this prospective study, we collected peripheral blood from twelve mCRPC patients and nine healthy donors before (baseline) and during treatment with Radium-223. Immunophenotyping and the percentages of leukocyte-platelet complexes were determined by flow cytometry. The increments or decrements of leukocyte subsets between the baseline and the second Radium-223 injection were also calculated. (3) Results: At baseline, the mCRPC patients had a lower percentages of CD4+ T cells and B cells and higher percentages of NK and neutrophils than the HDs. In addition, they had more OX40+ CD4+ T cells, PD-L1+ CD8low cells, PD-L1+ B cells, PD-L1+ NK cells, and monocyte-platelet complexes than the HDs. Moreover, patients with slow and fast progression had different percentages of PD-L1+ CD8+ T cells. In particular, slow progression patients underwent an increment of PD-L1+ CD8+ T cells after two cycles of Radium-223. (4) Conclusions: The characterization of circulating immune cells before initiating Radium-223 treatment could become a non-invasive indicator of the response.

Immune Response and Risk of Decompensation following SARS-CoV-2 Infection in Outpatients with Advanced Chronic Liver Disease

Advanced chronic liver disease (ACLD) is associated with a wide spectrum of immune dysfunction. The clinical impact of SARS-CoV-2 on the development of decompensation and immune response in unvaccinated outpatients has not as yet been clearly defined. This study aimed to evaluate the clinical and immunological impact of SARS-CoV-2 on outpatients with ACLD. This is an observational case-control study, in which ACLD outpatients were included prospectively and consecutively and classified into two groups: SARS-CoV-2 infected and non-infected. Patients' baseline characteristics and infection data were collected and analyzed. Immunoglobulin G (IgG) levels against Spike 1 were evaluated. The primary endpoint was risk of liver decompensation during follow-up, assessed after propensity score matching and adjusted by Cox regression. Between October 2020 and July 2021, ACLD outpatients (n = 580) were identified, and 174 patients with clinical follow-up were included. SARS-CoV-2 infection incidence was 7.6% (n = 44). Risk of liver decompensation was significantly higher after infection (HR = 2.43 [1.01-5.86], p = 0.048) vs. non-infection. The time of IgG evaluation was similar in all patients (n = 74); IgG concentrations were significantly higher in compensated vs. decompensated patients (1.02 ± 0.35 pg/mL vs. 0.34 ± 0.16 pg/mL, p < 0.0001) and correlated with hemoglobin levels. The dysregulation of the innate immune response in patients with decompensated liver disease increased the risk of further decompensation following SARS-CoV-2, mainly due to a worsening of ascites.