A scoping review of vasculitis as an immune-related adverse event from checkpoint inhibitor therapy of cancer: Unraveling the complexities at the intersection of immunology and vascular pathology.

BACKGROUND/PURPOSE: Vasculitis as an immune-related adverse event (irAE) from checkpoint inhibitor therapy (ICI) to treat cancer is a rare clinical event, and little is known regarding its nosology, clinical manifestations, or response to treatment and outcomes. METHODS: To address these gaps, we used the Preferred Reporting Items for Systemic Reviews and Meta-Analyses Extension for Scoping Reviews (PRISMA-ScR) framework to further define this complication. Two independent PUBMED searches in September and November of 2022 revealed 127 publications with 37 excluded from title by relevance, 43 excluded by article type, and 23 excluded due to lack of biopsy results, or biopsy negative for vasculitis. Twenty-nine documented cases from 24 publications were included for final analysis. Basic demographics, ICI details, timing of onset of vasculitis symptoms, irAE treatment and outcomes were collected. The vasculitides were classified using 2022 ACR/EULAR Vasculitis Classification Criteria as well as 2012 Revised Chapel-Hill Nomenclature. Adaptations from Naidoo et al. 2023 [1] consensus definitions for irAEs were used and efforts were made to classify steroid-responsive versus unresponsive irAEs. RESULTS: Of the 29 cases reviewed, the average age of patients was 62.1 ± 11.0, composed of 58.6 % (n = 17) male and 41.3 % (n = 12) female. Prominent cancer types were lung cancer (41.4 %; n = 12), melanoma (41.4 %; n = 12), and renal cancer (10.3 %; n = 3), with majority being stage 4 (75.9 %, n = 22) and stage 3 (10.3 %, n = 3). Only 8 cases met the ACR/EULAR criteria, and by Chapel-Hill Nomenclature, approximately a third were small-vessel vasculitis (31.0 %; n = 9) with n = 4 positive for ANCA. Most biopsies were taken from the skin (37.9 %, n = 11) and kidney (24.1 %, n = 7). Patients were either treated with single (65.5 %, n = 19), dual (17.2 %; n = 5), or sequential (17.2 %; n = 5) ICI regimen which included anti-PD-1 therapy in all but one case, with mean of 8.7 ± 10.5 cycles received. Mean time to onset of symptoms from start of ICI was 7.2 ± 7.8 months, with 55.2 % occurring >3 months since the initial immunotherapy. Vasculitis treatment included glucocorticoids in 96 % of cases and immunotherapy was often discontinued (44.8 %; n = 13). Clinical improvement of irAE was documented in 86.2 % (n = 25). Data were missing in terms of fate of ICI (34.5 %; n = 10) and tumor outcomes (41.4 %; n = 12). Cancer progressed in 20.7 % (n = 6), stable in 34.5 % (n = 10) cases, and 6 patients died of all-causes. CONCLUSION: Vasculitis as an irAE appears clinically heterogeneous and rare. Among reported cases with adequate documentation, vasculitis is of delayed onset following the initiation of immunotherapy. Outcomes of ICI-vasculitis were generally favorable, responding to glucocorticoids and immunotherapy withdrawal. There is an urgent need for more standardized reporting of rare irAEs such as vasculitis to clarify clinical risks, classification, relationship to immunotherapy and outcomes.

Mechanistic insights into bone remodelling dysregulation by human viral pathogens.

Bone-related diseases (osteopathologies) associated with human virus infections have increased around the globe. Recent findings have highlighted the intricate interplay between viral infection, the host immune system and the bone remodelling process. Viral infections can disrupt bone homeostasis, contributing to conditions such as arthritis and soft tissue calcifications. Osteopathologies can occur after arbovirus infections such as chikungunya virus, dengue virus and Zika virus, as well as respiratory viruses, such as severe acute respiratory syndrome coronavirus 2 and enteroviruses such as Coxsackievirus B. Here we explore how human viruses dysregulate bone homeostasis, detailing viral factors, molecular mechanisms, host immune response changes and bone remodelling that ultimately result in osteopathologies. We highlight model systems and technologies to advance mechanistic understanding of viral-mediated bone alterations. Finally, we propose potential prophylactic and therapeutic strategies, introduce 'osteovirology' as a research field highlighting the underestimated roles of viruses in bone-related diseases, and discuss research avenues for further investigation.

Rheumatology and Long COVID: lessons from the study of fibromyalgia.

Rheumatology, such as other subspecialties, has both a unique perspective to offer as well as an evolving role to play in the global COVID-19 pandemic. Our field has already contributed meaningfully to the development and repurposing of many of the immune-based therapeutics which are now standard treatments for severe forms of the disease as well as to the understanding of the epidemiology, risk factors and natural history of COVID-19 in immune-mediated inflammatory diseases. Still in evolution is our potential to contribute to burgeoning research efforts in the next phase of the pandemic: the syndrome of postacute sequelae of COVID-19 or Long COVID. While our field brings many assets to the study of Long COVID including our expertise in the investigation of chronic inflammation and autoimmunity, our Viewpoint focuses on the strong similarities between fibromyalgia (FM) and Long COVID. While one can speculate on how embracing and confident practising rheumatologists already are regarding these interrelationships, we assert that in the emerging field of Long COVID the potential lessons from the field of fibromyalgia care and research have been underappreciated and marginalised and most importantly now deserve a critical appraisal.

Cytomegalovirus Infection Facilitates the Costimulation of CD57+CD28- CD8 T Cells in HIV Infection and Atherosclerosis via the CD2-LFA-3 Axis.

CD8 T cells are emerging as important mediators in atherosclerosis and cardiovascular disease (CVD). Immune activation may play a particular role in people with HIV (PWH) who are at an increased risk of CVD, even after controlling for known CVD risk factors. Latent CMV infection is associated with increased CVD risk for both PWH and people without HIV, and human CMV-specific CD4 and CD8 T cells are enriched for an immunosenescent phenotype. We previously showed that CMV coinfection in PWH promotes vascular homing and activation of inflammatory CD4 T cells through the CD2-LFA-3 axis. However, the role of CD2/LFA3 costimulation of CD8 T cells in PWH with CMV has yet to be described. In the present study, we demonstrate that CD2 expression on CX3CR1+CD57+CD28- inflammescent CD8 T cells is increased on cells from CMV-seropositive PWH. In vitro CD2/LFA-3 costimulation enhances TCR-mediated activation of these inflammatory CD8 memory T cells. Finally, we show that LFA-3 is highly expressed in aortas of SIV-infected rhesus macaques and in atherosclerotic plaques of people without HIV. Our findings are consistent with a model in which CMV infection enhances CD2 expression on highly proinflammatory CD8 T cells that can then be stimulated by LFA-3 expressed in the vasculature, even in the absence of CD28 costimulation. This model, in which CMV infection exacerbates toxic cytokine and granzyme production by CD8 T cells within the vasculature, highlights a potential therapeutic target in atherosclerosis development and progression, especially for PWH.

Improving the nosology of Long COVID: it is not so simple.

Long COVID is a diagnostic label currently given to those suffering from a poorly understood state of incomplete recovery or who have development of a myriad of medically unexplained symptoms occurring in the wake of infection with SARS CoV-2 that is both poorly understood and controversial. Many of the features of one of the most common clinical endotypes of Long COVID are shared by a condition well familiar to all rheumatologists and one with a large body of epidemiologic, clinical and basic research accrued over many decades namely the syndrome of fibromyalgia. Some have recently suggested that Long COVID may merely be a new name for fibromyalgia and that this diagnosis is indeed the condition that many or most may be suffering from as a post infectious sequela. In this Viewpoint we argue that while the parallels between the clinical syndrome experienced by many of those currently labeled as Long COVID and fibromyalgia are strong we should be not too quick to rename the disorder. We further argue that relabeling Long COVID as fibromyalgia is clinically reductionistic and any such relabeling may be attended by harm in both the design and execution of a future research agenda as well to patients who may be inadvertently and unfortunately pejoritised by such labeling. We further explore the parallels and differences between Long COVID and fibromyalgia and outline areas of needed future research and care.

Self-evidence-based digital care programme improves health-related quality of life in adults with a variety of autoimmune diseases and long COVID: a retrospective study.

OBJECTIVE: To retrospectively investigate the feasibility and impact on health-related quality of life (HRQoL) of a digital care programme (DCP) designed to guide personalised diet and integrative interventions in a variety of autoimmune diseases and long COVID. METHODS: Adults who participated in the DCP between April 2020 and June 2022, and for whom baseline (BL) and end-of-programme (EOP) Patient-Reported Outcomes Measurement Information System (PROMIS) scores were available, were included in this retrospective study. Changes from BL to EOP were calculated using standardised T-scores. RESULTS: Two hundred two adults between 17 and 82 years old were included. Diagnoses included: rheumatoid arthritis (20.1%); long COVID (14.9%); psoriatic arthritis (10.9%); psoriasis (8.9%); systemic lupus erythematosus (6.4%); inflammatory bowel disease (5.9%); multiple sclerosis (5.9%); ankylosing spondylitis (5.4%) and other (23.3%). On average, individuals entered observations 7.6 times/day on 86% of programme days, attended 14 coach sessions and completed the programme in an average of 17.2 weeks. Statistically significant improvements were seen in all 10 PROMIS domains analysed. Individuals with higher severity of compromise at BL experienced greater average improvements than all-comers in all 10 PROMIS domains included. CONCLUSION: An evidence-based DCP that uses patient data to help identify hidden symptom triggers and guide personalised dietary and other non-pharmacological interventions was associated with a high level of engagement and adherence and statistically significant, clinically meaningful improvements in HRQoL. Those with the least favourable PROMIS scores at BL experienced the greatest improvements.

Interleukin 6 Blockade With Tocilizumab Diminishes Indices of Inflammation That Are Linked to Mortality in Treated Human Immunodeficiency Virus Infection.

BACKGROUND: People with human immunodeficiency virus (PWH) are at increased risk for comorbidities, and plasma interleukin 6 (IL-6) levels are among the most robust predictors of these outcomes. Tocilizumab (TCZ) blocks the receptor for IL-6, inhibiting functions of this cytokine. METHODS: This was a 40-week, placebo-controlled, crossover trial (NCT02049437) where PWH on stable antiretroviral therapy (ART) were randomized to receive 3 monthly doses of TCZ or matching placebo intravenously. Following a 10-week treatment period and a 12-week washout, participants were switched to the opposite treatment. The primary endpoints were safety and posttreatment levels of C-reactive protein (CRP) and CD4+ T-cell cycling. Secondary endpoints included changes in inflammatory indices and lipid levels. RESULTS: There were 9 treatment-related toxicities of grade 2 or greater during TCZ administration (mostly neutropenia) and 2 during placebo administration. Thirty-one of 34 participants completed the study and were included in a modified intent-to-treat analysis. TCZ reduced levels of CRP (median decrease, 1819.9 ng/mL, P < .0001; effect size, 0.87) and reduced inflammatory markers in PWH, including D-dimer, soluble CD14, and tumor necrosis factor receptors. T-cell cycling tended to decrease in all maturation subsets after TCZ administration, but was only significant among naive CD4 T cells. Lipid levels, including lipid classes that have been related to cardiovascular disease risk, increased during TCZ treatment. CONCLUSIONS: TCZ is safe and decreases inflammation in PWH; IL-6 is a key driver of the inflammatory environment that predicts morbidity and mortality in ART-treated PWH. The clinical significance of lipid elevations during TCZ treatment requires further study. Clinical Trials Registration. NCT02049437.

Clinical characteristics, brain magnetic resonance imaging findings and diagnostic approach of the primary central nervous system vasculitis according to angiographic classification.

OBJECTIVES: To determine the diagnostic accuracy for high-resolution vessel wall image (HR-VWI) and brain biopsy according to angiographical classification in patients with primary central nervous system vasculitis (PCNSV). METHODS: We extracted the patients with PCNSV who underwent the complete brain MRI protocol and cerebral vascular image from Cleveland Clinic prospective CNS vasculopathy Bioregistry. The large-medium vessel variant (LMVV) was defined as patients with cerebral vasculature indicating vasculitis in proximal or middle arterial segments, whereas vessel involvements in smaller distal branches or normal angiography were considered as the small vessel variant (SVV). We compared clinical demographics, magnetic resonance imaging (MRI) findings, and diagnostic approaches between two variants. RESULTS: In this case-control study that included 34 PCNSV patients, the LMVV group comprised a total of 11 patients (32.4%), and 23 patients (67.6%) were classified as the SVV group. The LMVV had more strong/concentric vessel wall enhancement on HR-VWI (LMVV: 90% (9/10) vs. SVV: 7.1% (1/14), p<0.001). By contrast, meningeal/parenchymal contrast enhancement lesion was more frequently observed in the SVV group (p=0.006). The majority of SVV was diagnosed by brain biopsy (SVV: 78.3% vs. LMVV: 30.8%, p=0.022). The diagnostic accuracy of the brain biopsy was 100% (18/18) in SVV and 57.1% (4/7) in LMVV, respectively (p=0.015). CONCLUSIONS: Diagnostic approach for PCNSV differs concerning the affected vessel size. HR-VWI is a useful imaging modality for the diagnosis of LMVV. Brain biopsy remains the gold standard for proving PCNSV with SVV but is still positive in almost one-third of LMVV.

2022 American College of Rheumatology Guideline for Vaccinations in Patients With Rheumatic and Musculoskeletal Diseases.

OBJECTIVE: To provide evidence-based recommendations on the use of vaccinations in children and adults with rheumatic and musculoskeletal diseases (RMDs). METHODS: This guideline follows American College of Rheumatology (ACR) policy guiding management of conflicts of interest and disclosures and the ACR guideline development process, which includes the Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology. It also adheres to the Appraisal of Guidelines for Research and Evaluation (AGREE) criteria. A core leadership team consisting of adult and pediatric rheumatologists and a guideline methodologist drafted clinical population, intervention, comparator, outcomes (PICO) questions. A review team performed a systematic literature review for the PICO questions, graded the quality of evidence, and produced an evidence report. An expert Voting Panel reviewed the evidence and formulated recommendations. The panel included adult and pediatric rheumatology providers, infectious diseases specialists, and patient representatives. Consensus required ≥70% agreement on both the direction and strength of each recommendation. RESULTS: This guideline includes expanded indications for some vaccines in patients with RMDs, as well as guidance on whether to hold immunosuppressive medications or delay vaccination to maximize vaccine immunogenicity and efficacy. Safe approaches to the use of live attenuated vaccines in patients taking immunosuppressive medications are also addressed. Most recommendations are conditional and had low quality of supporting evidence. CONCLUSION: Application of these recommendations should consider patients' individual risk for vaccine-preventable illness and for disease flares, particularly if immunosuppressive medications are held for vaccination. Shared decision-making with patients is encouraged in clinical settings.

2022 American College of Rheumatology Guideline for Vaccinations in Patients With Rheumatic and Musculoskeletal Diseases.

OBJECTIVE: To provide evidence-based recommendations on the use of vaccinations in children and adults with rheumatic and musculoskeletal diseases (RMDs). METHODS: This guideline follows American College of Rheumatology (ACR) policy guiding management of conflicts of interest and disclosures and the ACR guideline development process, which includes the Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology. It also adheres to the Appraisal of Guidelines for Research and Evaluation (AGREE) criteria. A core leadership team consisting of adult and pediatric rheumatologists and a guideline methodologist drafted clinical population, intervention, comparator, outcomes (PICO) questions. A review team performed a systematic literature review for the PICO questions, graded the quality of evidence, and produced an evidence report. An expert Voting Panel reviewed the evidence and formulated recommendations. The panel included adult and pediatric rheumatology providers, infectious diseases specialists, and patient representatives. Consensus required ≥70% agreement on both the direction and strength of each recommendation. RESULTS: This guideline includes expanded indications for some vaccines in patients with RMDs, as well as guidance on whether to hold immunosuppressive medications or delay vaccination to maximize vaccine immunogenicity and efficacy. Safe approaches to the use of live attenuated vaccines in patients taking immunosuppressive medications are also addressed. Most recommendations are conditional and had low quality of supporting evidence. CONCLUSION: Application of these recommendations should consider patients' individual risk for vaccine-preventable illness and for disease flares, particularly if immunosuppressive medications are held for vaccination. Shared decision-making with patients is encouraged in clinical settings.

Opportunistic infections associated with Janus kinase inhibitor treatment for rheumatoid arthritis: A structured literature review.

BACKGROUND: The availability of Janus kinase (JAK) inhibitors has transformed the management of rheumatoid arthritis (RA), helping patients achieve clinical remission. However, the emergence of opportunistic infections (OIs) associated with the use of JAK inhibitors has been reported. This structured literature review was conducted to summarize reports of OIs associated with JAK inhibitor treatment for RA in clinical trials. METHODS: Structured searches were performed in MEDLINE® and Embase® to identify relevant clinical trial data through March 2021. Bibliographic searches of recent reviews were also conducted, and gray literature searches were used to supplement key gap areas. Publications were screened, extracted, and quality assessed. Data were narratively synthesized. RESULTS: Following screening, 105 publications describing 62 unique clinical trials reporting the rates of OIs in RA patients treated with JAK inhibitors were included. Overall, the highest exposure-adjusted incidence rate was reported for herpes zoster (HZ) infection (any form), followed by OI (any) and tuberculosis based on limited data from clinical trials with approved doses of JAK inhibitors. Lack of head-to-head trials and differences in trial design preclude direct comparison across JAK inhibitors. Higher rates of OIs were noted in the Asian and Australian populations compared with the global population. Higher rates of OIs were also noted with increasing dose of JAK inhibitors in most clinical trial data. CONCLUSIONS: HZ was the most common OI reported among RA patients using all currently approved JAK inhibitors in clinical trials, although tuberculosis and other OIs were also reported. More long-term safety studies in the real-world setting are needed to compare the risk of OIs between various JAK inhibitors.

Can numerical rating scales of disease impact be used as targets for patient-centred management in rheumatoid arthritis?

OBJECTIVES: Patient centred care is an increasingly important paradigm. Applying a treat-to-target strategy to the impact of the disease in patients' lives seems a very promising tool to serve this purpose. We aimed to evaluate if maximum acceptable impact scores (target-values) defined at the population level provide an appropriate representation for most individual patients. To determine if the individually established target values of impact are consistent enough to be used in a treat-to-target strategy. METHODS: Consecutive patients with rheumatoid arthritis were asked to indicate, in two consecutive visits, the maximum severity of impact they considered acceptable to live with for the rest of their lives, in the seven domains of Rheumatoid Arthritis Impact of Disease score. The individual adequacy of population-based reference values was assessed by measures of dispersion. Stability of individual target-values were evaluated through intraclass correlation coefficient. Socio-demographic, clinical and psychological features were tested as co-factors of stability. RESULTS: 299 patients were included. The dispersion of targets was wide (CV>0.68), thus limiting the use of any population-based single values as targets for the individual patients. Although the mean target values were very similar in both visits for all domains, reliability was poor in all cases (ICCs: 0.37-0.47). Only 25-30% of the patients selected the same target value in the 2 visits. No explanatory factors for (non-)stability were identified. CONCLUSIONS: Quantified impact targets defined at population level are not appropriate for individual patient care. Research on alternative tools to support patient-centred, target-oriented management strategies is warranted.

Long COVID and rheumatology: Clinical, diagnostic, and therapeutic implications.

As of this writing, it is estimated that there have been nearly 600 million cases of coronavirus disease 2019 (COVID-19) around the world with over six million deaths. While shocking, these figures do not fully illustrate the morbidity associated with this disease. It is also estimated that between 10% and 30% of those who survive COVID-19 develop persistent symptoms after the acute infection has passed. These individuals, who most often experienced initial infections with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) considered mild to moderate in severity, often display a broad array of symptoms. Collectively, this disorder or syndrome is now referred to as Long COVID (among other designations), and it represents a national/international health crisis. The most frequently reported symptoms associated with Long COVID include chronic fatigue with post exertional features, neurocognitive dysfunction, breathlessness, and somatic pain. Long COVID can range in severity from mild to severely debilitating, with resultant loss of quality of life and productivity. For now, there are many unanswered questions surrounding Long COVID: how can it be best defined, what is needed for accurate diagnosis, what is causing it, and how should it be best managed. How rheumatologists will engage in the Long COVID pandemic is another question; at the minimum, we will be called upon to evaluate and manage our own patients with immune-mediated inflammatory diseases who have developed it. This review focuses on addressing the disease essentials, providing both declarative and procedural knowledge to prepare rheumatologists for how to address Long COVID: understanding its origins, its current case definitions, epidemiology, pathobiology and clinical manifestations. Finally, it will provide an outline on how to clinically approach patients with possible Long COVID and initiate treatment and/or guide them on how to best manage it.

Online, low-volume meditation does not alter immune-related biomarkers.

Objectives: Prior studies of mindfulness meditation have demonstrated anti-inflammatory and immunoregulatory effects but whether meditation courses delivered online can exert similar effects is poorly understood. Barriers to large scale implementation of traditional mindfulness meditation programs has created an increased interest in the effect of less time- and resource-intensive online meditation courses. The purpose of this study was to determine whether a 6-week online mindfulness program with low time demands on nurses would lead to changes in gene expression, cytokine profiles, telomerase activity, and cortisol profiles. Methods: This was a randomized, parallel pilot study comparing an online mindfulness-based stress management program to an active control group from December 2018 to May 2019. Healthy nurses with above average levels of perceived stress were randomized to receive a 6-week online mindfulness-based stress management program including ≥5 min daily meditation practice or listen to relaxing music for ≥5 min daily as the control arm. Blood samples were collected at baseline and after 6 weeks, and various self-reported measures of stress, physical and emotional health were collected at baseline, after 6 weeks, and after 12 weeks. Whole transcriptome mRNA sequencing of whole blood at baseline and after 6 weeks was performed along with measurement of plasma IL-6, IL-8, IL-10, TNF-α, and IFN-γ. Peripheral blood mononuclear cells were isolated, and telomerase activity was measured. Diurnal salivary cortisol profiles were assessed at baseline and after 6 weeks. The primary outcome was change over time in a pre-determined set of 53 genes representative of the immune-related changes seen with stress, which was analyzed using a mixed linear model. Secondary outcomes included all other self-reported measures and biomarkers mentioned above. Results: A total of 61 nurses were randomized, with 52 having sufficient data to include in the final analysis. After 6 weeks, nurses in the control group reported significant reductions in stress as measured by the Perceived Stress Scale while those in the mindfulness group did not. However, after 12 weeks, the mindfulness group also showed a significant reduction in stress. When compared to the control group, no significant changes in RNA gene expression or any other biomarkers were observed in the nurses who participated in the mindfulness program. Conclusions: Our study found that this brief online mindfulness-based intervention was effective in reducing stress in nurses, albeit with a delayed effect compared to listening to relaxing music. Regarding immunoregulatory effects, there were no significant differences between treatment and control groups in transcriptomic or other tested biomarkers of immune function. This study provides evidence for a floor effect of mindfulness on transcriptional and circulating biomarkers of immune function.

Methotrexate Inhibits T Cell Proliferation but Not Inflammatory Cytokine Expression to Modulate Immunity in People Living With HIV.

Inflammation associated with increased risk of comorbidities persists in people living with HIV (PWH) on combination antiretroviral therapy (ART). A recent placebo-controlled trial of low-dose methotrexate (MTX) in PWH found that numbers of total CD4 and CD8 T cells decreased in the low-dose MTX arm. In this report we analyzed T cell phenotypes and additional plasma inflammatory indices in samples from the trial. We found that cycling (Ki67+) T cells lacking Bcl-2 were reduced by MTX but plasma inflammatory cytokines were largely unaffected. In a series of in vitro experiments to further investigate the mechanisms of MTX activity, we found that MTX did not inhibit effector cytokine production but inhibited T cell proliferation downstream of mTOR activation, mitochondrial function, and cell cycle entry. This inhibitory effect was reversible with folinic acid, suggesting low-dose MTX exerts anti-inflammatory effects in vivo in PWH largely by blocking T cell proliferation via dihydrofolate reductase inhibition, yet daily administration of folic acid did not rescue this effect in trial participants. Our findings identify the main mechanism of action of this widely used anti-inflammatory medicine in PWH and may provide insight into how MTX works in the setting of other inflammatory conditions.

Breakthrough SARS-CoV-2 Infections in Patients With Immune-Mediated Disease Undergoing B Cell-Depleting Therapy: A Retrospective Cohort Analysis.

OBJECTIVE: Patients with immune-mediated inflammatory diseases (IMIDs) receiving B cell-depleting therapy (BCDT) are among the most vulnerable to severe COVID-19, as well as the most likely to suboptimally respond to SARS-CoV-2 vaccines. However, little is known about the frequency or severity of breakthrough infection in this population. We retrospectively analyzed a large group of vaccinated IMID patients undergoing BCDT in order to identify breakthrough COVID-19 infections and assess their outcomes. METHODS: In this retrospective cohort study, the pharmacy records and COVID-19 registry at the Cleveland Clinic were searched using specific International Statistical Classification of Diseases and Related Health Problems, Tenth Revision codes to identify IMIDs patients who 1) received treatment with BCDT, 2) were vaccinated against SARS-CoV-2, and 3) experienced breakthrough infections. Each electronic medical record was reviewed to extract clinical data and outcomes. Univariate and multivariable logistic/proportional odds regression models were used to examine the risk factors for severe outcomes. RESULTS: Of 1,696 IMID patients receiving BCDT, 74 developed breakthrough COVID-19 prior to December 16, 2021. Outcomes were severe, with 29 patients hospitalized (39.2%), 11 patients requiring critical care (14.9%), and 6 deaths (8.1%). Outpatient anti-SARS-CoV-2 monoclonal antibodies were used to treat 21 patients, with 1 hospitalization and no deaths. A comparator analysis examining 1,437 unvaccinated IMID patients receiving BCDT over the same time period identified 57 COVID-19 cases (4.0%), with 28 requiring hospitalization (49.1%), including 7 deaths (12.3%). CONCLUSION: IMID patients receiving BCDT regardless of vaccine status appear to be vulnerable to infection with SARS-CoV-2, and use of BCDT is frequently associated with severe outcomes. Outpatient use of anti-SARS-CoV-2 monoclonal antibody therapy appears to be associated with enhanced clinical outcomes.