Real-world reporting rates of administration-site reactions with on-demand treatment of hereditary angioedema attacks

Background: Hereditary angioedema (HAE) is characterized by recurrent and unpredictable episodes of subcutaneous and/or submucosal swelling. Objective: To characterize the real-world treatment burden associated with existing on-demand therapies, we analyzed administration-site adverse drug reactions (ADR) associated with approved on-demand HAE therapies reported in the U.S. Food and Drug Administration's (FDA) Adverse Event Reporting System (FAERS). Methods: We searched the FAERS database from October 1, 2009, to March 31, 2022, for reports of all FDA-approved on-demand therapies for HAE: plasma-derived C1-inhibitor (pdC1-INH), ecallantide, icatibant, and recombinant C1-inhibitor (rhC1-INH). ADRs in which the drug was listed as the "primary suspect" were recorded for each drug. ADR preferred terms were grouped into 18 ADR domains based on semantic and/or clinical similarity, and the number of reports for each drug was calculated per year from the time of approval through March 2022, and descriptive results were presented. Preferred terms associated with administration-site ADRs identified from clinical trials and denoted on approved HAE drug U.S. package inserts were examined in a complementary analysis. Results: The highest reported rates of administration-site ADRs per year were site pain (17.9 reports per year), site erythema (7.4 per year), and site swelling (6.7 per year). RhC1-INH was the only drug for which access-site complications and/or malfunctions were reported (9.5 per year). PdC1-INH had the highest rate of incorrect route of product administration (3.7 per year). PdC1-INH showed statistically significant elevated reporting rate of injection-site reactions (reporting odds ratio [ROR] 3.59 [2.36-5.46]; empirical Bayesian geometric mean [EBGM] 1.97 [1.39]). Icatibant and rhC1-INH showed a statistical trend toward an increased reporting rate of administration-site reactions. Conclusion: Real-world data from FAERS were generally consistent with adverse events reported in clinical trials and suggest that patients experience substantial treatment burden associated with FDA-approved parenteral on-demand therapies for HAE attacks. It should be noted that ADR rates are not exposure adjusted and are based on spontaneous reporting.

Rab46: a novel player in mast cell function

Mast cells are infamous for mediating allergic and inflammatory diseases due to their capacity of rapidly releasing a wide range of inflammatory mediators stored in cytoplasmic granules. However, mast cells also have several important physiological roles that involve selective and agonist-specific release of these active mediators. While a filtering mechanism at the plasma membrane could regulate the selective release of some cargo, the plethora of stored cargo and the diversity of mast cell functions suggests the existence of granule subtypes with distinct trafficking pathways. The molecular mechanisms underlying differential trafficking and exocytosis of these granules are not known, neither is it clear how granule trafficking is coupled to the stimulus. In endothelial cells, a Rab GTPase, Rab46, responds to histamine but not thrombin signals, and this regulates the trafficking of a subpopulation of endothelial-specific granules. Here, we sought to explore, for the first time, if Rab46 plays a role in mast cell function. We demonstrate that Rab46 is highly expressed in human and murine mast cells, and Rab46 genetic deletion has an effect on mast cell degranulation that depends on both stimuli and mast cell subtype. This initial insight into the contribution of Rab46 to mast cell function and the understanding of the role of Rab46 in stimuli-dependent trafficking in other cell types necessitates further investigations of Rab46 in mast cell granular trafficking so that novel and specific therapeutic targets for treatment of the diverse pathologies mediated by mast cells can be developed.

Activated phosphoinositide 3-kinase δ syndrome: Update from the ESID Registry and comparison with other autoimmune-lymphoproliferative inborn errors of immunity

BACKGROUND

Activated phosphoinositide-3-kinase δ syndrome (APDS) is an inborn error of immunity (IEI) with infection susceptibility and immune dysregulation, clinically overlapping with other conditions. Management depends on disease evolution, but predictors of severe disease are lacking.

OBJECTIVES

This study sought to report the extended spectrum of disease manifestations in APDS1 versus APDS2; compare these to CTLA4 deficiency, NFKB1 deficiency, and STAT3 gain-of-function (GOF) disease; and identify predictors of severity in APDS.

METHODS

Data was collected from the ESID (European Society for Immunodeficiencies)-APDS registry and was compared with published cohorts of the other IEIs.

RESULTS

The analysis of 170 patients with APDS outlines high penetrance and early onset of APDS compared to the other IEIs. The large clinical heterogeneity even in individuals with the same PIK3CD variant E1021K illustrates how poorly the genotype predicts the disease phenotype and course. The high clinical overlap between APDS and the other investigated IEIs suggests relevant pathophysiological convergence of the affected pathways. Preferentially affected organ systems indicate specific pathophysiology: bronchiectasis is typical of APDS1; interstitial lung disease and enteropathy are more common in STAT3 GOF and CTLA4 deficiency. Endocrinopathies are most frequent in STAT3 GOF, but growth impairment is also common, particularly in APDS2. Early clinical presentation is a risk factor for severe disease in APDS.

CONCLUSIONS

APDS illustrates how a single genetic variant can result in a diverse autoimmune-lymphoproliferative phenotype. Overlap with other IEIs is substantial. Some specific features distinguish APDS1 from APDS2. Early onset is a risk factor for severe disease course calling for specific treatment studies in younger patients.

Inherited CD19 Deficiency Does Not Impair Plasma Cell Formation or Response to CXCL12

BACKGROUND

The human CD19 antigen is expressed throughout B cell ontogeny with the exception of neoplastic plasma cells and a subset of normal plasma cells. CD19 plays a role in propagating signals from the B cell receptor and other receptors such as CXCR4 in mature B cells. Studies of CD19-deficient patients have confirmed its function during the initial stages of B cell activation and the production of memory B cells; however, its role in the later stages of B cell differentiation is unclear.

OBJECTIVE

Using B cells from a newly identified CD19-deficient individual, we investigated the role of CD19 in the generation and function of plasma cells using an in vitro differentiation model.

METHODS

Flow cytometry and long-read nanopore sequencing using locus-specific long-range amplification products were used to screen a patient with suspected primary immunodeficiency. Purified B cells from the patient and healthy controls were activated with CD40L, IL-21, IL-2, and anti-Ig, then transferred to different cytokine conditions to induce plasma cell differentiation. Subsequently, the cells were stimulated with CXCL12 to induce signalling through CXCR4. Phosphorylation of key downstream proteins including ERK and AKT was assessed by Western blotting. RNA-seq was also performed on in vitro differentiating cells.

RESULTS

Long-read nanopore sequencing identified the homozygous pathogenic mutation c.622del (p.Ser208Profs*19) which was corroborated by the lack of CD19 cell surface staining. CD19-deficient B cells that are predominantly naïve generate phenotypically normal plasma cells with expected patterns of differentiation-associated genes and normal levels of CXCR4. Differentiated CD19-deficient cells were capable of responding to CXCL12; however, plasma cells derived from naïve B cells, both CD19-deficient and sufficient, had relatively diminished signaling compared to those generated from total B cells. Additionally, CD19 ligation on normal plasma cells results in AKT phosphorylation.

CONCLUSION

CD19 is not required for generation of antibody-secreting cells or the responses of these populations to CXCL12, but may alter the response other ligands that require CD19 potentially affecting localization, proliferation, or survival. The observed hypogammaglobulinemia in CD19-deficient individuals is therefore likely attributable to the lack of memory B cells.

Penicillin allergy status and its effect on antibiotic prescribing, patient outcomes and antimicrobial resistance (ALABAMA): protocol for a multicentre, parallel-arm, open-label, randomised pragmatic trial

INTRODUCTION

Incorrect penicillin allergy records are recognised as an important barrier to the safe treatment of infection and affect an estimated 2.7 million people in England. Penicillin allergy records are associated with worse health outcome and antimicrobial resistance. The ALlergy AntiBiotics And Microbial resistAnce (ALABAMA) trial aims to determine if an intervention package, centred around a penicillin allergy assessment pathway (PAAP) initiated in primary care, is safe and effective in improving patient health outcomes and antibiotic prescribing.

METHODS AND ANALYSIS

The ALABAMA trial is a multicentre, parallel-arm, open-label, randomised pragmatic trial with a nested pilot study. Adults (≥18 years) with a penicillin allergy record and who have received antibiotics in the previous 24 months will be eligible for participation. Between 1592 and 2090 participants will be recruited from participating National Health Service general practices in England. Participants will be randomised to either usual care or intervention to undergo a pre-emptive PAAP using a 1:1 allocation ratio. The primary outcome measure is the percentage of treatment response failures within 28 days of an index prescription. 2090 and 1592 participants are estimated to provide 90% and 80% power, respectively, to detect a clinically important absolute difference of 7.9% in primary outcome at 1 year between groups. The trial includes a mixed-methods process evaluation and cost-effectiveness evaluation.

ETHICS AND DISSEMINATION

This trial has been approved by London Bridge Research Ethics Committee (ref: 19/LO/0176). It will be conducted in compliance with Good Clinical Practice guidelines according to the Declaration of Helsinki. Informed consent will be obtained from all subjects involved in the study. The primary trial results will be submitted for publication to an international, peer-reviewed journal.

TRIAL REGISTRATION

ISRCTN20579216.

Prevalence of CFTR variants in primary immunodeficiency patients with bronchiectasis is an important modifying cofactor

BACKGROUND

Cystic fibrosis (CF) is one of the most common life-limiting autosomal-recessive disorders and is caused by genetic defects in the CF transmembrane conductance regulator (CFTR) gene. Some of the features of this multisystem disease can be present in primary immunodeficiency (PID).

OBJECTIVE

We hypothesized that a carrier CFTR status might be associated with worse outcome regarding structural lung disease in patients with PID.

METHODS

A within-cohort and population-level statistical genomic analysis of a large European cohort of PID patients was performed using genome sequence data. Genomic analysis of variant pathogenicity was performed.

RESULTS

Compared to the general population, p.Phe508del carriage was enriched in lung-related PID. Additionally, carriage of several pathogenic CFTR gene variants were increased in PID associated with structural lung damage compared to PID patients without the structural lung damage. We identified 3 additional biallelic cases, including several variants not traditionally considered to cause CF.

CONCLUSION

Genome sequencing identified cases of CFTR dysfunction in PID, driving an increased susceptibility to infection. Large national genomic services provide an opportunity for precision medicine by interpreting subtle features of genomic diversity when treating traditional Mendelian disorders.

Breakthrough SARS-CoV-2 infections and prediction of moderate-to-severe outcomes during rituximab therapy in patients with rheumatic and musculoskeletal diseases in the UK: a single-centre cohort study

Background

Concerns have been raised regarding the reduced immunogenicity of vaccines against COVID-19 in patients with autoimmune diseases treated with rituximab. However, the incidence and severity of breakthrough infections in unbiased samples of patients with specific rheumatic and musculoskeletal diseases are largely unknown. We aimed to assess the incidence of breakthrough SARS-CoV-2 infection, compare rates of moderate-to-severe COVID-19 with any severe infection event, and evaluate predictors of moderate-to-severe COVID-19 outcomes in patients treated with rituximab.

Methods

We did a retrospective cohort study in all rituximab-treated patients with rheumatic and musculoskeletal diseases in a single centre in Leeds, UK between March 1, 2020 (the index date), and April 1, 2022. Adults aged 18 years and older, who fulfilled classification criteria for established rheumatic and musculoskeletal diseases, and received therapy with at least one rituximab infusion between Sept 1, 2019 (6 months before the pandemic in the UK), and April 1, 2022, were eligible for inclusion in the study. SARS-CoV-2 infection was defined by antigen test or PCR. COVID-19 outcomes were categorised as mild (from ambulatory to hospitalised but not requiring oxygen support) or moderate-to-severe (hospitalised and requiring oxygen support or death). The primary outcome was breakthrough COVID-19 infection, which was defined as an infection occurring 14 days or more after the second vaccine dose. Predictors of moderate-to-severe COVID-19 outcomes were analysed using Cox regression proportional hazards.

Findings

Of the 1280 patients who were treated with at least one cycle of rituximab since Jan 1, 2002, 485 (38%) remained on rituximab therapy on April 1, 2022. Of these patients, 400 fulfilled all inclusion criteria and were included in our final analysis. The mean age at the index date was 58·9 years (SD 14·6), 288 (72%) of 400 patients were female and 112 (28%) were male, 333 (83%) were White, and 110 (28%) had two or more comorbidities. 272 (68%) of 400 patients had rheumatoid arthritis, 48 (12%) had systemic lupus erythematosus, 48 (12%) had anti-neutrophil cytoplasmic antibody-associated vasculitis, and 46 (12%) had other rheumatic and musculoskeletal diseases. During the study, 798 rituximab cycles were administered. Of the 398 (>99%) of 400 patients with vaccine data, 372 (93%) were fully vaccinated. Over the 774·6 patient-years of follow-up, there was an incremental increase in all SARS-CoV-2 severity types over the three pandemic phases (wild-type or alpha, delta, and omicron), but most infections were mild. The rates of moderate-to-severe COVID-19 were broadly similar across these three variant phases. Of 370 patients who were fully vaccinated and with complete data, 110 (30%) had all severity type breakthrough COVID-19, 16 (4%) had moderate-to-severe breakthrough COVID-19, and one (<1%) died. In the post-vaccination phase (after Dec 18, 2020), the incidence rates of all severity type and moderate-to-severe COVID-19 were substantially lower in those who were fully vaccinated compared with unvaccinated or partially vaccinated individuals (22·83 per 100 person-years [95% CI 18·94-27·52] in those who were fully vaccinated vs 89·46 per 100 person-years [52·98-151·05] in those who were partially vaccinated or unvaccinated for infections of all severities, and 3·32 per 100 person-years [2·03-5·42] in those who were fully vaccinated vs 25·56 per 100 person-years [9·59-68·10] in those who were partially vaccinated or unvaccinated for moderate-to-severe infections). The rate of moderate-to-severe COVID-19 was broadly similar to other severe infection events in this cohort (5·68 per 100 person-years [95% CI 4·22-7·63]). In multivariable Cox regression analysis, factors associated with an increased risk of moderate-to-severe COVID-19 were the number of comorbidities (hazard ratio 1·46 [95% CI 1·13-1·89]; p=0·0037) and hypogammaglobulinaemia (defined by a pre-rituximab IgG concentration of <6 g/L; 3·22 [1·27-8·19]; p=0·014). This risk was reduced with each vaccine dose received (0·49 [0·37-0·65]; p<0·0001). Other factors, including concomitant prednisolone use, rituximab-associated factors (eg, rituximab dose and time to vaccination since last rituximab dose), and vaccine-associated factors (eg, vaccine type and peripheral B-cell depletion) were not predictive of moderate-to-severe COVID-19 outcomes.

Interpretation

This study presented detailed analyses of rituximab-treated patients during various phases of the COVID-19 pandemic. In later stages of the pandemic, the SARS-CoV-2 breakthrough infection rate was high but severe COVID-19 rates were similar to any severe infection event rate in patients who were vaccinated. The risk-benefit ratio might still favour rituximab in vaccinated patients with severe rheumatic and musculoskeletal diseases who have few other treatment options. Increased vigilance is needed in the presence of comorbidities and hypogammaglobulinaemia for all infection types.

Funding

Wellcome Trust and Eli Lilly.

An update on VEXAS syndrome

INTRODUCTION

VEXAS (vacuoles, E1 enzyme, X-linked, autoinflammatory, somatic) syndrome is a recently described, late-onset, acquired autoinflammatory disorder caused by mutations in the UBA1 gene. The various clinical manifestations of VEXAS broadly divided into inflammatory or haematological. VEXAS defines a new disease category - the hematoinflammatory disorders triggered by somatic mutations restricted to blood but causing systemic inflammation with multi-organ involvement and associated with aberrant bone marrow status. VEXAS causes significant morbidity and reduced life expectancy, but the optimum standard of care remains undefined.

AREAS COVERED

This review describes the discovery of VEXAS, relevant genetic causes and immunopathology of the disease. A detailed account of its various clinical manifestations and disease mimics is provided. Current treatment and management options are discussed.

EXPERT OPINION

New rare variants in UBA1 and VEXAS-like UBA1 negative cases are reported. Consensus diagnostic criteria might be required to define VEXAS and its related disorders. Investigation of sporadic, VEXAS-like cases will require the application of deep sequencing using DNA obtained from various cellular or tissue locations. Prospective studies are needed to define the optimal supportive and treatment options for patients with varying disease severity and prognosis. VEXAS-specific hematopoietic stem cell transplant selection criteria also require development.

Unveiling chronic spontaneous urticaria pathophysiology through systems biology

BACKGROUND

Chronic spontaneous urticaria (CSU) is a rare, heterogeneous, severely debilitating, and often poorly controlled skin disease resulting in an itchy eruption that can be persistent. Antihistamines and omalizumab, an anti-IgE mAb, are the only licensed therapies. Although CSU pathogenesis is not yet fully understood, mast cell activation through the IgE:high-affinity IgE receptor (FcεRI) axis appears central to the disease process.

OBJECTIVE

We sought to model CSU pathophysiology and identify in silico the mechanism of action of different CSU therapeutic strategies currently in use or under development.

METHODS

Therapeutic performance mapping system technology, based on systems biology and machine learning, was used to create a CSU interactome validated with gene expression data from patients with CSU and a CSU model that was used to evaluate CSU pathophysiology and the mechanism of action of different therapeutic strategies.

RESULTS

Our models reflect the known role of mast cell activation as a central process of CSU pathophysiology, as well as recognized roles for different therapeutic strategies in this and other innate and adaptive immune processes. They also allow determining similarities and differences between them; anti-IgE and Bruton tyrosine kinase inhibitors play a more direct role in mast cell biology through abrogation of FcεRI signaling activity, whereas anti-interleukins and anti-Siglec-8 have a role in adaptive immunity modulation.

CONCLUSION

In silico CSU models reproduced known CSU and therapeutic strategies features. Our results could help advance understanding of therapeutic mechanisms of action and further advance treatment research by patient profile.

Cost-effectiveness of personalized omalizumab dosing for chronic spontaneous urticaria

The licensed dose for omalizumab within Europe for chronic spontaneous urticaria (CSU) is 300 mg every 4 weeks, and is based on the most effective dose identified in clinical trials. However, many patients require longer-term treatment with omalizumab and there is limited guidance on how to manage these patients. We report on a large cohort of 357 patients with CSU who have been treated over a 10-year period on a personalized dosing regimen. Our results showed a 4% reduction in drug cost for this personalized dosing regimen compared with having all patients on the standard regimen of omalizumab 300 mg every 4 weeks. In addition, by increasing the dose, we were able to treat 22% of patients more effectively, using the principle aim of zero CSU symptoms; prior to this regimen, these patients had been achieving only partial response. Omalizumab doses and frequency should be adjusted depending on clinical response to allow for improved benefits for both patients and healthcare systems.

A bovine antibody possessing an ultralong complementarity-determining region CDRH3 targets a highly conserved epitope in sarbecovirus spike proteins

Broadly neutralizing antibodies have huge potential as novel antiviral therapeutics due to their ability to recognize highly conserved epitopes that are seldom mutated in viral variants. A subset of bovine antibodies possess an ultralong complementarity-determining region (CDR)H3 that is highly adept at recognizing such conserved epitopes, but their reactivity against Sarbecovirus Spike proteins has not been explored previously. Here, we use a SARS-naïve library to isolate a broadly reactive bovine CDRH3 that binds the receptor-binding domain of SARS-CoV, SARS-CoV-2, and all SARS-CoV-2 variants. We show further that it neutralizes viruses pseudo-typed with SARS-CoV Spike, but this is not by competition with angiotensin-converting enzyme 2 (ACE2) binding. Instead, using differential hydrogen-deuterium exchange mass spectrometry, we demonstrate that it recognizes the major site of vulnerability of Sarbecoviruses. This glycan-shielded cryptic epitope becomes available only transiently via interdomain movements of the Spike protein such that antibody binding triggers destruction of the prefusion complex. This proof of principle study demonstrates the power of in vitro expressed bovine antibodies with ultralong CDRH3s for the isolation of novel, broadly reactive tools to combat emerging pathogens and to identify key epitopes for vaccine development.

Improving Diagnosis and Clinical Management of Acquired Systemic Autoinflammatory Diseases

Systemic autoinflammatory diseases (SAID) are conditions caused by dysregulation or disturbance of the innate immune system, with neutrophils and macrophages the main effector cells. Although there are now more than 40 distinct, genetically defined SAIDs, the genetic/molecular diagnosis remains unknown for a significant proportion of patients with the disease onset in adulthood. This review focuses on new developments related to acquired/late onset SAID, including phenocopies of monogenic disorders, Schnitzler's syndrome, Adult onset Still's disease, VEXAS syndrome, and autoinflammatory complications associated with myelodysplastic syndrome.

Outcomes following SARS-CoV-2 infection in patients with primary and secondary immunodeficiency in the UK

In March 2020, the United Kingdom Primary Immunodeficiency Network (UKPIN) established a registry of cases to collate the outcomes of individuals with PID and SID following SARS-CoV-2 infection and treatment. A total of 310 cases of SARS-CoV-2 infection in individuals with PID or SID have now been reported in the UK. The overall mortality within the cohort was 17.7% (n = 55/310). Individuals with CVID demonstrated an infection fatality rate (IFR) of 18.3% (n = 17/93), individuals with PID receiving IgRT had an IFR of 16.3% (n = 26/159) and individuals with SID, an IFR of 27.2% (n = 25/92). Individuals with PID and SID had higher inpatient mortality and died at a younger age than the general population. Increasing age, low pre-SARS-CoV-2 infection lymphocyte count and the presence of common co-morbidities increased the risk of mortality in PID. Access to specific COVID-19 treatments in this cohort was limited: only 22.9% (n = 33/144) of patients admitted to the hospital received dexamethasone, remdesivir, an anti-SARS-CoV-2 antibody-based therapeutic (e.g. REGN-COV2 or convalescent plasma) or tocilizumab as a monotherapy or in combination. Dexamethasone, remdesivir, and anti-SARS-CoV-2 antibody-based therapeutics appeared efficacious in PID and SID. Compared to the general population, individuals with PID or SID are at high risk of mortality following SARS-CoV-2 infection. Increasing age, low baseline lymphocyte count, and the presence of co-morbidities are additional risk factors for poor outcome in this cohort.

Translation of cytoplasmic UBA1 contributes to VEXAS syndrome pathogenesis

Somatic mutations in UBA1 cause vacuoles, E1 ubiquitin-activating enzyme, X-linked, autoinflammatory somatic (VEXAS) syndrome, an adult-onset inflammatory disease with an overlap of hematologic manifestations. VEXAS syndrome is characterized by a high mortality rate and significant clinical heterogeneity. We sought to determine independent predictors of survival in VEXAS and to understand the mechanistic basis for these factors. We analyzed 83 patients with somatic pathogenic variants in UBA1 at p.Met41 (p.Met41Leu/Thr/Val), the start codon for translation of the cytoplasmic isoform of UBA1 (UBA1b). Patients with the p.Met41Val genotype were most likely to have an undifferentiated inflammatory syndrome. Multivariate analysis showed ear chondritis was associated with increased survival, whereas transfusion dependence and the p.Met41Val variant were independently associated with decreased survival. Using in vitro models and patient-derived cells, we demonstrate that p.Met41Val variant supports less UBA1b translation than either p.Met41Leu or p.Met41Thr, providing a molecular rationale for decreased survival. In addition, we show that these 3 canonical VEXAS variants produce more UBA1b than any of the 6 other possible single-nucleotide variants within this codon. Finally, we report a patient, clinically diagnosed with VEXAS syndrome, with 2 novel mutations in UBA1 occurring in cis on the same allele. One mutation (c.121 A>T; p.Met41Leu) caused severely reduced translation of UBA1b in a reporter assay, but coexpression with the second mutation (c.119 G>C; p.Gly40Ala) rescued UBA1b levels to those of canonical mutations. We conclude that regulation of residual UBA1b translation is fundamental to the pathogenesis of VEXAS syndrome and contributes to disease prognosis.

Impact of vaccination on hospitalization and mortality from COVID-19 in patients with primary and secondary immunodeficiency: The United Kingdom experience

Background

Individuals with primary and secondary immunodeficiency (PID/SID) were shown to be at risk of poor outcomes during the early stages of the SARS-CoV-2 pandemic. SARS-CoV-2 vaccines demonstrate reduced immunogenicity in these patients.

Objectives

To understand whether the risk of severe COVID-19 in individuals with PID or SID has changed following the deployment of vaccination and therapeutics in the context of the emergence of novel viral variants of concern.

Methods

The outcomes of two cohorts of patients with PID and SID were compared: the first, infected between March and July 2020, prior to vaccination and treatments, the second after these intervention became available between January 2021 and April 2022.

Results

22.7% of immunodeficient patients have been infected at least once with SARS-CoV-2 since the start of the pandemic, compared to over 70% of the general population. Immunodeficient patients were typically infected later in the pandemic when the B.1.1.529 (Omicron) variant was dominant. This delay was associated with receipt of more vaccine doses and higher pre-infection seroprevalence. Compared to March-July 2020, hospitalization rates (53.3% vs 17.9%, p<0.0001) and mortality (Infection fatality rate 20.0% vs 3.4%, p=0.0003) have significantly reduced for patients with PID but remain elevated compared to the general population. The presence of a serological response to vaccination was associated with a reduced duration of viral detection by PCR in the nasopharynx. Early outpatient treatment with antivirals or monoclonal antibodies reduced hospitalization during the Omicron wave.

Conclusions

Most individuals with immunodeficiency in the United Kingdom remain SARS-CoV-2 infection naïve. Vaccination, widespread availability of outpatient treatments and, possibly, the emergence of the B.1.1.529 variant have led to significant improvements in morbidity and mortality followings SARS-CoV-2 infection since the start of the pandemic. However, individuals with PID and SID remain at significantly increased risk of poor outcomes compared to the general population; mitigation, vaccination and treatment strategies must be optimized to minimize the ongoing burden of the pandemic in these vulnerable cohorts.

Partial RAG deficiency in humans induces dysregulated peripheral lymphocyte development and humoral tolerance defect with accumulation of T-bet+ B cells

The recombination-activating genes (RAG) 1 and 2 are indispensable for diversifying the primary B cell receptor repertoire and pruning self-reactive clones via receptor editing in the bone marrow; however, the impact of RAG1/RAG2 on peripheral tolerance is unknown. Partial RAG deficiency (pRD) manifesting with late-onset immune dysregulation represents an ‘experiment of nature’ to explore this conundrum. By studying B cell development and subset-specific repertoires in pRD, we demonstrate that reduced RAG activity impinges on peripheral tolerance through the generation of a restricted primary B cell repertoire, persistent antigenic stimulation and an inflammatory milieu with elevated B cell-activating factor. This unique environment gradually provokes profound B cell dysregulation with widespread activation, remarkable extrafollicular maturation and persistence, expansion and somatic diversification of self-reactive clones. Through the model of pRD, we reveal a RAG-dependent ‘domino effect’ that impacts stringency of tolerance and B cell fate in the periphery.

Patients with partial recombination-activating gene (RAG) deficiency (pRD) present variable late-onset autoimmune clinical phenotypes. Walter and colleagues identified a restricted primary B cell antigen receptor repertoire enriched for autoreactivity and clonal persistence in pRD. They described dysregulated B cell maturation with expansion of T-bet⁺ B cells revealing how RAG impacts stringency of tolerance and B cell fate in the periphery.

SARS-CoV-2 Vaccine Responses in Individuals with Antibody Deficiency: Findings from the COV-AD Study

BACKGROUND

Vaccination prevents severe morbidity and mortality from COVID-19 in the general population. The immunogenicity and efficacy of SARS-CoV-2 vaccines in patients with antibody deficiency is poorly understood.

OBJECTIVES

COVID-19 in patients with antibody deficiency (COV-AD) is a multi-site UK study that aims to determine the immune response to SARS-CoV-2 infection and vaccination in patients with primary or secondary antibody deficiency, a population that suffers from severe and recurrent infection and does not respond well to vaccination.

METHODS

Individuals on immunoglobulin replacement therapy or with an IgG less than 4 g/L receiving antibiotic prophylaxis were recruited from April 2021. Serological and cellular responses were determined using ELISA, live-virus neutralisation and interferon gamma release assays. SARS-CoV-2 infection and clearance were determined by PCR from serial nasopharyngeal swabs.

RESULTS

A total of 5.6% (n = 320) of the cohort reported prior SARS-CoV-2 infection, but only 0.3% remained PCR positive on study entry. Seropositivity, following two doses of SARS-CoV-2 vaccination, was 54.8% (n = 168) compared with 100% of healthy controls (n = 205). The magnitude of the antibody response and its neutralising capacity were both significantly reduced compared to controls. Participants vaccinated with the Pfizer/BioNTech vaccine were more likely to be seropositive (65.7% vs. 48.0%, p = 0.03) and have higher antibody levels compared with the AstraZeneca vaccine (IgGAM ratio 3.73 vs. 2.39, p = 0.0003). T cell responses post vaccination was demonstrable in 46.2% of participants and were associated with better antibody responses but there was no difference between the two vaccines. Eleven vaccine-breakthrough infections have occurred to date, 10 of them in recipients of the AstraZeneca vaccine.

CONCLUSION

SARS-CoV-2 vaccines demonstrate reduced immunogenicity in patients with antibody deficiency with evidence of vaccine breakthrough infection.

Mixed-methods evaluation of a behavioural intervention package to identify and amend incorrect penicillin allergy records in UK general practice

OBJECTIVES

About 6% of the UK general practice population has a record of a penicillin allergy but fewer than 10% of these are likely to be truly allergic. In the ALABAMA (Allergy Antibiotics and Microbial resistance) feasibility trial, primary care patients with penicillin allergy were randomised to penicillin allergy assessment pathway or usual care to assess the effect on health outcomes. A behavioural intervention package was developed to aid delabelling. This study aimed to investigate patients' and clinicians' views of penicillin allergy testing (PAT).

DESIGN

We conducted a mixed-methods process evaluation embedded within the ALABAMA trial, which included a clinician survey, a patient survey (at baseline and follow-up) and semistructured interviews with patients and clinicians.

SETTINGS

The study was conducted in primary care, as part of the feasibility stage of the ALABAMA trial.

PARTICIPANTS

Patients and primary care clinicians.

RESULTS

Clinicians (N=53; 52.2%) were positive about PAT and its potential value but did not have previous experience of referring patients for a PAT and were unsure whether patients would take penicillin after a negative allergy test. Patients (N=36; 46%) were unsure whether they were severely allergic to penicillin and did not fear a severe allergic reaction to penicillin. Clinician interviews showed that they were already aware of the benefit of PAT. Interviews with patients suggested the importance of safety as patients valued having numerous opportunities to address their concerns about safety of the test.

CONCLUSIONS

This study highlights the positive effects of the ALABAMA behavioural intervention for both patients and clinicians.

TRIAL REGISTRATION NUMBER

NCT04108637; ISRCTN20579216; Pre-results.

Increased Seroprevalence and Improved Antibody Responses Following Third Primary SARS-CoV-2 Immunisation: An Update From the COV-AD Study

Background

Patients with primary and secondary antibody deficiency are vulnerable to COVID-19 and demonstrate diminished responses following two-dose SARS-CoV-2 vaccine schedules. Third primary vaccinations have been deployed to enhance their humoral and cellular immunity.

Objectives

To determine the immunogenicity of the third primary SARS-CoV-2 immunisation in a heterogeneous cohort of patients with antibody deficiency.

Methods

Participants enrolled in the COV-AD study were sampled before and after their third vaccine dose. Serological and cellular responses were determined using ELISA, live-virus neutralisation and ELISPOT assays.

Results

Following a two-dose schedule, 100% of healthy controls mounted a serological response to SARS-CoV-2 vaccination, however, 38.6% of individuals with antibody deficiency remained seronegative. A third primary SARS-CoV-2 vaccine significantly increased anti-spike glycoprotein antibody seroprevalence from 61.4% to 76.0%, the magnitude of the antibody response, its neutralising capacity and induced seroconversion in individuals who were seronegative after two vaccine doses. Vaccine-induced serological responses were broadly cross-reactive against the SARS-CoV-2 B.1.1.529 variant of concern, however, seroprevalence and antibody levels remained significantly lower than healthy controls. No differences in serological responses were observed between individuals who received AstraZeneca ChAdOx1 nCoV-19 and Pfizer BioNTech 162b2 during their initial two-dose vaccine schedule. SARS-CoV-2 infection-naive participants who had received a heterologous vaccine as a third dose were significantly more likely to have a detectable T cell response following their third vaccine dose (61.5% vs 11.1%).

Conclusion

These data support the widespread use of third primary immunisations to enhance humoral immunity against SARS-CoV-2 in individuals with antibody deficiency.

OP0250 BREAKTHROUGH INFECTIONS AND PREDICTING SEVERE COVID OUTCOMES DURING RITUXIMAB THERAPY IN AUTOIMMUNE RHEUMATIC DISEASES

Background

As rituximab (RTX) is a B-cell depleting agent, there are concerns regarding its safety during the COVID pandemic. Data from registries during pre-vaccination period reported increased risk of poor outcomes in RTX-treated patients vs TNFi. However, registry data could be limited by reporting bias in determining true incidence. There are also limited data on breakthrough infections following COVID vaccination.

Objectives

To assess the incidence of breakthrough infections and predictors of severe COVID outcomes in RTX-treated autoimmune rheumatic diseases (ARDs) with a view to establishing a treatment algorithm for safe RTX administration.

Methods

An observational cohort study was undertaken in the first consecutive 300 ARD patients in a single centre between index date 01/09/2019 (i.e. 6 months prior to pandemic) and 31/01/2022. Only PCR positive cases were included. COVID outcomes were categorised as Mild (i.e. not hospitalised) or Moderate/Severe (i.e. hospitalised and requiring at least oxygenation or death). Predictors of moderate/severe outcomes were analysed using Cox-regression proportional hazard.

Results

Mean (SD) at index date was 59 (14) years, 226/300 (75%) patients were female and 254 (85%) were Caucasians. The diagnoses were RA=212 (71%), SLE=33 (11%), AAV=26 (9%), Sjogren=9 (3%), IIM=8 (3%) and others=12 (4%). Therapy included concomitant DMARDs = 205 (68%) and oral prednisolone = 84 (28%). Median (range) no. of previous RTX courses was 4 (0-19). 534 RTX courses were administered. Of 294 patients with available vaccine data, 17 (6%) were unvaccinated, 4 (1%) had a single dose, 47 (16%) were double-vaccinated, 217 (74%) triple-vaccinated and 9 (3%) quadruple-vaccinated. Of those who were vaccinated, for the first dose, 11% were given within 12 weeks post-RTX, 15% within 26 weeks and 74% were >26 weeks post-RTX. The rate of overall COVID and moderate/severe infections were 11.2/100 PYs and 2.6/100 PYs respectively. Vaccinated patients had lower rate of moderate/severe infection (2.6/100 PYs) vs unvaccinated (18.6/100 PYs) [Table 1]. Over 650.7 PY follow-up, 17/300 patients (5.7%) had moderate/severe COVID including 2 deaths. Factors associated with time-to-infection in imputed multivariable analysis were number of comorbidities [HR 1.46 (95% CI 1.05-2.04)] and low IgG (<6g/L) [6.15 (1.95-19.41)]. A history of COVID vaccination reduced risk [HR 0.13 (0.03-0.51)]. Demographics including concomitant prednisolone, RTX- and vaccine-associated factors (e.g. RTX dose, time from RTX to vaccine, vaccine mode, peripheral B-cell depletion) were not predictive.

Table 1.

Incidence of COVID infection

Pre-Vaccination ProgrammePost-Vaccination ProgrammeOverall Follow-upOverall COVID rate3.3/100 PYNon-vaccinated = 37.7/100 PY73 cases in 650.7 years] = 11.2/100 PYVaccinated = 18.6/100 PYModerate/Severe COVID rate2.1/100 PYNon-Vaccinated = 15.1/100 PY17 cases in 650.7 years] = 2.6/100 PYVaccinated = 2.6/100 PY

Conclusion

The rate of moderate/severe COVID infection in this cohort is comparable to the pre-pandemic severe infection rate in rituximab trials in RA. The high vaccination uptake in our cohort was effective in preventing severe infection despite the termination of national shielding programme in March 2021 and the spread of the Delta and Omicron variants. Individualised risk–benefit assessment should be undertaken in those with comorbidities, low IgG and unvaccinated when scheduling rituximab therapy.

References

None

Acknowledgements

This research was funded/supported by the the Wellcome Trust Institutional Strategic Support Fund to MYMY (204825/Z/16/Z), National Institute for Health Research (NIHR) Doctoral Research Fellowship to MYMY (DRF-2014-07-155) and NIHR Clinician Scientist to EMV (CS-2013-13-032). PE is a Versus Arthritis Professor of Rheumatology. This article/paper/report also presents independent research funded/supported by the NIHR Leeds Biomedical Research Centre. The views expressed are those of the author(s) and not necessarily those of the NIHR or the Department of Health and Social Care.

Disclosure of Interests

Md Yuzaiful Md Yusof Consultant of: Aurinia Pharmaceuticals, Jack Arnold: None declared, Benazir Saleem: None declared, Claire Vandevelde: None declared, Shouvik Dass: None declared, Sinisa Savic Speakers bureau: Novartis, Swedish Orphan Biovitrum (SOBI) and Sire, Grant/research support from: Novartis, Swedish Orphan Biovitrum, Octapharma and CSL Behring, Edward Vital Speakers bureau: Roche, GSK and AstraZeneca, Grant/research support from: Roche, GSK and AstraZeneca, Paul Emery Consultant of: BMS, Abbott, Pfizer, MSD, Novartis, Roche and UCB, Grant/research support from: Abbott, BMS, Pfizer, MSD and Roche.

Ruxolitinib in addition to standard of care for the treatment of patients admitted to hospital with COVID-19 (RUXCOVID): a randomised, double-blind, placebo-controlled, phase 3 trial

Background

COVID-19 is associated with acute respiratory distress and cytokine release syndrome. The Janus kinase (JAK)1/JAK2 inhibitor ruxolitinib reduces inflammatory cytokine concentrations in disorders characterised by cytokine dysregulation, including graft-versus-host disease, myelofibrosis, and secondary hemophagocytic lymphohistiocytosis. We assessed whether treatment with the JAK1/JAK2 inhibitor ruxolitinib would be beneficial in patients with COVID-19 admitted to hospital.

Methods

RUXCOVID was an international, randomised, double-blind, phase 3 trial of ruxolitinib plus standard of care versus placebo plus standard of care in patients with COVID-19. Patients who were hospitalised but not on mechanical ventilation or in the intensive care unit [ICU] were randomly assigned (2:1) to oral ruxolitinib 5 mg twice per day or placebo for 14 days (14 additional days were allowed if no improvement). The primary endpoint was a composite of death, respiratory failure (invasive ventilation), or ICU care by day 29, analysed by logistic regression including region, treatment, baseline clinical status, age, and sex as covariates. This trial is registered with ClinicalTrials.gov, NCT04362137.

Findings

Between May 4 and Sept 19, 2020, 432 patients were randomly assigned to ruxolitinib (n=287) or placebo (n=145) plus standard of care; the mean age was 56·5 years (SD 13·3), 197 (46%) were female, and 235 (54%) were male. The primary objective was not met: the composite endpoint occurred in 34 (12%) of 284 ruxolitinib-treated patients versus 17 (12%) of 144 placebo-treated patients (odds ratio 0·91, 95% CI 0·48-1·73; p=0·77). By day 29, nine (3%) of 286 ruxolitinib-treated patients had died compared with three (2%) of 145 placebo-treated patients; 22 (8%) of 286 ruxolitinib-treated patients had received invasive ventilation compared with ten (7%) of 145 placebo-treated patients; and 30 (11%) of 284 ruxolitinib-treated patients had received ICU care compared with 17 (12%) of 144 placebo-treated patients. In an exploratory analysis, median time to recovery was 1 day faster with ruxolitinib versus placebo (8 days vs 9 days; hazard ratio 1·10, 95% CI 0·89-1·36). Adverse events included headache (23 [8%] of 281 on ruxolitinib vs 11 [8%] of 143 on placebo) and diarrhoea (21 [7%] vs 12 [8%]).

Interpretation

Ruxolitinib 5 mg twice per day showed no benefit in the overall study population. A larger sample is required to determine the clinical importance of trends for increased efficacy in patient subgroups.

Funding

Novartis and Incyte.

Tocilizumab in patients hospitalised with COVID-19 pneumonia: Efficacy, safety, viral clearance, and antibody response from a randomised controlled trial (COVACTA)

BACKGROUND

In COVACTA, a randomised, placebo-controlled trial in patients hospitalised with coronavirus disease-19 (COVID-19), tocilizumab did not improve 28-day mortality, but shortened hospital and intensive care unit stay. Longer-term effects of tocilizumab in patients with COVID-19 are unknown. Therefore, the efficacy and safety of tocilizumab in COVID-19 beyond day 28 and its impact on Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) clearance and antibody response in COVACTA were investigated.

METHODS

Adults in Europe and North America hospitalised with COVID-19 (N = 452) between April 3, 2020 and May 28, 2020 were randomly assigned (2:1) to double-blind intravenous tocilizumab or placebo and assessed for efficacy and safety through day 60. Assessments included mortality, time to hospital discharge, SARS-CoV-2 viral load in nasopharyngeal swab and serum samples, and neutralising anti-SARS-CoV-2 antibodies in serum. ClinicalTrials.gov registration: NCT04320615.

FINDINGS

By day 60, 24·5% (72/294) of patients in the tocilizumab arm and 25·0% (36/144) in the placebo arm died (weighted difference -0·5% [95% CI -9·1 to 8·0]), and 67·0% (197/294) in the tocilizumab arm and 63·9% (92/144) in the placebo arm were discharged from the hospital. Serious infections occurred in 24·1% (71/295) of patients in the tocilizumab arm and 29·4% (42/143) in the placebo arm. Median time to negative reverse transcriptase-quantitative polymerase chain reaction result in nasopharyngeal/oropharyngeal samples was 15·0 days (95% CI 14·0 to 21·0) in the tocilizumab arm and 21·0 days (95% CI 14·0 to 28·0) in the placebo arm. All tested patients had positive test results for neutralising anti-SARS-CoV-2 antibodies at day 60.

INTERPRETATION

There was no mortality benefit with tocilizumab through day 60. Tocilizumab did not impair viral clearance or host immune response, and no new safety signals were observed. Future investigations may explore potential biomarkers to optimize patient selection for tocilizumab treatment and combination therapy with other treatments.

FUNDING

F. Hoffmann-La Roche Ltd and the US Department of Health and Human Services, Office of the Assistant Secretary for Preparedness and Response, Biomedical Advanced Research and Development Authority, under OT number HHSO100201800036C.

P037 A patient with systemic inflammation, relapsing polychondritis and pancytopaenia: VEXAS

Background/Aims

We report a patient presenting with an inflammatory illness consistent with relapsing polychondritis (RP) and a pancytopaenia. Testing of his bone marrow revealed confirmation of the somatic mutation for the newly recognised condition VEXAS (vacuoles, E1 enzyme, X-linked, autoinflammatory, somatic) syndrome. VEXAS is an acquired, adult-onset autoinflammatory syndrome which is progressive and frequently fatal. First reported in October 2020 by Beck et al, it results from somatic mutations at methionine-41 (p.Met41) of UBA1 gene, the major E1 enzyme that initiates ubiquitylation. Clinical features of VEXAS include periodic fevers, neutrophilic dermatoses, pulmonary infiltrates, chondritis and venous thromboembolic events. Bone marrow biopsy (BMB) shows vacuoles in myeloid precursor cells, and these cause hematologic abnormalities like myelodysplastic syndrome, multiple myeloma, or monoclonal gammopathy of unknown significance.

Methods

Clinical details were collected retrospectively. UBA1 sequencing: UBA1 exon 3 (NM_153280) was amplified from using High-Fidelity Phusion Polymerase (Life Tech) and primers UBA1-3F and UBA1-3R. PCR products were sequenced using the BigDye v3.1 terminator sequencing kit on an ABI3130xl (Life Tech). Electropherograms were analysed using 4Peaks software.

Results

A previously fit 63-year-old gentleman presented with a three-month history of recurrent fevers, night sweats and intermittent cough. At presentation he also had left testicular pain. Bloods showed neutropenia (1.9x10^9/L), normocytic anaemia (128g/L) and raised CRP (98mg/L). However, his symptoms progressed with headaches, myalgia, conjunctivitis, nasal chondritis and sinusitis. His CRP rose to 149mg/L and ferritin was 886ng/mL. He had a negative PET scan, autoimmune screen, myeloma screen and normal levels of complement, CK and ACE. Furthermore, multiple blood cultures and infectious disease screening tests were negative. He subsequently developed a left auricular chondritis. Within a week of commencing prednisolone 40mg and methotrexate 15mg his symptoms improved by 80% and his CRP was 10mg/L. At 15mg of prednisolone his CRP rose (134mg/L) and his fevers, night sweats and arthralgia returned. His prednisolone was then increased to 20mg. Over the next nine months his disease progressed despite prednisolone and methotrexate. He developed worsening cytopenias (Hb86/L, plts105x109/L, MCV117fL), bilateral sclerouveitis, inflammatory joint pains, vasculitic rash, chest pain and dyspnoea on exertion. CTPA and HRCT showed no significant abnormalities. VEXAS syndrome was diagnosed after BMB testing identified the UBA1 mutation c.122T&gt;c, p.Met41Thr. His treatment now encompasses prednisolone and Tocilizumab. His cytopenias are transfusion dependent, he has been under review to consider BMT although is currently stable clinically.

Conclusion

VEXAS syndrome should be considered in men over 50 with treatment-refractory giant cell arteritis, RP, polyarteritis nodosa and Sweet’s syndrome. VEXAS has a significant mortality and developing effective treatments is a priority. Given there is an available confirmatory test early recognition and subsequent testing for the UBA1 mutation will help physicians to identify appropriate treatment options and avoid unnecessary investigations.

Disclosure

S. Sajawal: None. M. Green: None. S. Savic: Consultancies; Novartis, SOBI, TAKEDA. Member of speakers’ bureau; Novartis, SOBI. Grants/research support; SOBI.

Identification of a novel MAGT1 mutation supports a diagnosis of XMEN disease

XMEN (X-linked immunodeficiency with magnesium defect) is caused by loss-of-function mutations in MAGT1 which is encoded on the X chromosome. The disorder is characterised by CD4 lymphopenia, severe chronic viral infections and defective T-lymphocyte activation. XMEN patients are susceptible to Epstein-Barr virus infections and persistently low levels of intracellular Mg²⁺. Here we describe a patient that presented with multiple recurrent infections and a subsequent diffuse B-cell lymphoma. Molecular genetic analysis by exome sequencing identified a novel hemizygous MAGT1 nonsense mutation c.1005T>A (NM_032121.5) p.(Cys335*), confirming a diagnosis of XMEN deficiency. Follow-up immunophenotyping was performed by antibody staining and flow cytometry; proliferation was determined by ³H-thymidine uptake after activation by PHA and anti-CD3. Cytotoxic natural killer cell activity was assessed with K562 target cells using the NKTEST^TM assay. While lymphocyte populations were superficially intact, B cells were largely naive with a reduced memory cell compartment. Translated NKG2D was absent on both NK and T cells in the proband, and normally expressed in the carrier mother. In vitro NK cell activity was intact in both the proband and his mother. This report adds to the growing number of identified XMEN cases, raising awareness of a, still rare, X-linked immunodeficiency.

A Personalized Rituximab Retreatment Approach Based on Clinical and B-Cell Biomarkers in ANCA-Associated Vasculitis

Background

Time to relapse after rituximab for the treatment of antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is variable, and optimal retreatment strategy has remained unclear. In AAV following rituximab induction, the study objective was to evaluate clinical and B-cell predictors of relapse in order to develop a retreatment algorithm.

Methods

A retrospective observational study was conducted in 70 rituximab-treated ANCA-associated vasculitis patients followed up for over 10 years. Complete response (CR) was defined as Birmingham Vasculitis Activity Score v3.0 = 0. Retreatment was given on clinical relapse, defined as new features or worsening of persistent disease (not by biomarker status). Peripheral B-cell subsets were measured using highly sensitive flow cytometry. Predictors were tested using multivariable Cox regression.

Results

Median time to retreatment for cycles 1–5 were 84, 73, 67, 60, and 73 weeks. Over 467 patient-years follow-up, 158 relapses occurred in 60 patients; 16 (in 15 patients) were major (renal = 7, neurological = 4, ENT = 3, and respiratory = 2). The major-relapse rate was 3.4/100 patient-years. In multivariable analysis, concomitant immunosuppressant [HR, 0.48 (95% CI, 0.24–0.94)], achieving CR [0.24 (0.12–0.50)], and naïve B-cell repopulation at 6 months [0.43 (0.22–0.84)] were associated with longer time to relapse. Personalized retreatment using these three predictors in this cohort would have avoided an unnecessary fixed retreatment in 24% of patients. Area under the receiver operating characteristic for prediction of time to relapse was greater if guided by naïve B-cell repopulation than if previously evaluated ANCA and/or CD19⁺ cells return at 6 months had been used, 0.82 and 0.53, respectively.

Conclusion

Our findings suggest that all patients should be coprescribed oral immunosuppressant. Those with incomplete response or with absent naïve B cells should be retreated at 6 months. Patients with complete response and naïve repopulation should not receive fixed retreatment. This algorithm could reduce unnecessary retreatment and warrant investigation in clinical trials.

Mandatory vaccination of National Health Service staff against COVID-19: more harm than good?

Despite the clear benefits of vaccination against COVID-19, there was significant unease relating to the government policy of mandatory vaccination of health and care staff in England and the potential inequities this may lead to. Healthcare staff, and in particular doctors, speaking out on this issue may have inadvertently provided a narrative, which undermined the objective of achieving widespread vaccination of populations against this serious disease. The recent reversal of this policy may not mark the end of this debate amongst health and social care staff.

Treatment of chronic or relapsing COVID-19 in immunodeficiency

BACKGROUND

Patients with some types of immunodeficiency can experience chronic or relapsing infection with severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). This leads to morbidity and mortality, infection control challenges, and the risk of evolution of novel viral variants. The optimal treatment for chronic coronavirus disease 2019 (COVID-19) is unknown.

OBJECTIVE

Our aim was to characterize a cohort of patients with chronic or relapsing COVID-19 disease and record treatment response.

METHODS

We conducted a UK physician survey to collect data on underlying diagnosis and demographics, clinical features, and treatment response of immunodeficient patients with chronic (lasting ≥21 days) or relapsing (≥2 episodes) of COVID-19.

RESULTS

We identified 31 patients (median age 49 years). Their underlying immunodeficiency was most commonly characterized by antibody deficiency with absent or profoundly reduced peripheral B-cell levels; prior anti-CD20 therapy, and X-linked agammaglobulinemia. Their clinical features of COVID-19 were similar to those of the general population, but their median duration of symptomatic disease was 64 days (maximum 300 days) and individual patients experienced up to 5 episodes of illness. Remdesivir monotherapy (including when given for prolonged courses of ≤20 days) was associated with sustained viral clearance in 7 of 23 clinical episodes (30.4%), whereas the combination of remdesivir with convalescent plasma or anti-SARS-CoV-2 mAbs resulted in viral clearance in 13 of 14 episodes (92.8%). Patients receiving no therapy did not clear SARS-CoV-2.

CONCLUSIONS

COVID-19 can present as a chronic or relapsing disease in patients with antibody deficiency. Remdesivir monotherapy is frequently associated with treatment failure, but the combination of remdesivir with antibody-based therapeutics holds promise.

Autoinflammation: Interferonopathies and Other Autoinflammatory Diseases

The family of autoinflammatory diseases (AIDs) continues to expand and now includes over 40 genetically defined disorders. Their defining feature is a dysregulated inflammatory innate immune response. Many AIDs have overlapping clinical characteristics, and dermatological manifestations are common. Autoinflammatory features have also been recognized in more common dermatological conditions such as psoriasis. Furthermore, there is an increasing understanding that immunodeficiencies, autoimmune disorders, and even some allergic disorders share overlapping autoinflammatory features. The discovery that certain somatic mutations, arising within the bone marrow and restricted to the myeloid cell lineage can cause acquired AID heralds a new era of discoveries in this field.

Genetics of somatic auto-inflammatory disorders

Systemic autoinflammatory disorders (SAIDs) encompass a heterogeneous group of monogenic disorders characterized by recurrent episodes of systemic and organ-specific inflammation. Genetic studies have facilitated the identification of Mendelian forms of SAIDs but many patients still remain without a diagnosis. Recent studies have uncovered that somatic (acquired) mutations can cause later-onset SAIDs. In this review, we will discuss the current knowledge surrounding the genetics of these acquired auto-inflammatory disorders (AAIDs), with a focus on VEXAS, NLRP3-associated AAIDs and Schnitzler's syndrome and provide suggestions for future research in this field.

Sustained safety and efficacy of ligelizumab in patients with chronic spontaneous urticaria: A one-year extension study

BACKGROUND

Ligelizumab, a next-generation, humanized anti-immunoglobulin E (IgE) monoclonal antibody is in development as a treatment for patients with chronic spontaneous urticaria, whose symptoms are inadequately controlled with standard-of-care therapy.

OBJECTIVE

To evaluate the long-term safety and re-treatment efficacy of ligelizumab 240 mg in patients who completed the core study and extension study.

METHODS

This open-label, single-arm, long-term Phase 2b extension study was designed to assess patients who were previously administered various doses of ligelizumab, omalizumab or placebo in the Phase 2b, dose-finding core study and who presented with active disease after Week 32. In the extension study, patients received ligelizumab 240 mg subcutaneously every 4 weeks, for 52 weeks and were monitored post-treatment for 48 weeks.

RESULTS

Overall, ligelizumab was well-tolerated with no newly identified safety signals. A total of 95.4% (226/237) screened patients received ligelizumab 240 mg in the extension study; 84.1% (190/226) of patients experienced at least one treatment-emergent adverse event. Most reported events were mild (41.6%) or moderate (35.8%) and mostly unrelated to the study treatment. At Week 12, 46.5% of patients had a complete response increasing to 53.1% after 52 weeks. Following 52 weeks of extension study treatment, 75.8% (95% confidence interval, 69.9, 81.3) of patients had cumulative complete responses. The median time to relapse in complete responders was 38 weeks.

CONCLUSION

The long-term safety profile of ligelizumab 240 mg in patients with chronic spontaneous urticaria was consistent with the core study and re-treatment efficacy was shown.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02477332 and NCT02649218.

An Atypical Autoinflammatory Disease Due to an LRR Domain NLRP3 Mutation Enhancing Binding to NEK7

The NLRP3 inflammasome is a vital mediator of innate immune responses. There are numerous NLRP3 mutations that cause NLRP3-associated autoinflammatory diseases (NLRP3-AIDs), mostly in or around the NACHT domain. Here, we present a patient with a rare leucine-rich repeat (LRR) domain mutation, p.Arg920Gln (p.R920Q), associated with an atypical NLRP3-AID with recurrent episodes of sore throat and extensive oropharyngeal ulceration. Unlike previously reported patients, who responded well to anakinra, her oral ulcers did not significantly improve until the PDE4 inhibitor, apremilast, was added to her treatment regimen. Here, we show that this mutation enhances interactions between NLRP3 and its endogenous inhibitor, NIMA-related kinase 7 (NEK7), by affecting charge complementarity between the two proteins. We also demonstrate that additional inflammatory mediators, including the NF-кB and IL-17 signalling pathways and IL-8 chemokine, are upregulated in the patient’s macrophages and may be directly involved in disease pathogenesis. These results highlight the role of the NLRP3 LRR domain in NLRP3-AIDs and demonstrate that the p.R920Q mutation can cause diverse phenotypes between families.

One Health in Urban environment- public health challenge for the future

Urban environment is a specific one in which are citizens and also their pets and other animals looking for a mutual place for a qualitative life. Humans are trying to make their life as good as possible, bringing the “nature” inside urban environment, but not always thinking through if urban environment will have effect on that “nature” - pets and plants in houses. The availability of data on number of pets in urban environments is being studied. It is estimated that in a city of 500.000 inhabitants, there are around 17.000 dogs, but number of cats is even more challenging to find. Which towns are the highlighted ones with developed culture of cohabitation? The ones with equally developed conditions for the life “of all. WHO (1990) suggests that dog ecology and related anthropological aspects can serve to establish background information for the planning and implementation of dog population management schemes and for the control of zoonotic diseases. Dog population density is related to different habitats, cultures, and social conditions of human populations (Fielding and Plumridge 2005). For example, Albert and Bulcroft (2015) in their study underline the important social and emotional roles that pets play in the urban household. People in cities demonstrate high levels of attachment, caring, and intimacy towards their pets. Pets are viewed as important members of households and owners are willing to spend high budget of money on needed medical or preventive care for their pets. One health concept in an urban environment has a specific significance from overcoming common risks for humans and animals point of view. The risk of infectious diseases is probably the most common one, including zoonotic diseases. This risk can even be a life threating one. There is also the risk of non-infectious diseases and influence of the mental health of owners to pet's life. Also, the influence of owner's life style to the life of pets - eating, walking and other habits.

SARS-CoV-2 diagnostics: Towards a more comprehensive approach to routine patient testing

The SARS-CoV-2 pandemic has provided the stimulus for the rapid development of a variety of diagnostic testing methods. Initially these were deployed as screening tools to evidence spread of the virus within populations. The recent availability of vaccines against the virus and the need to better understand the parameters of post-infection protective immunity requires development of methods, suitable for use in the routine diagnostic laboratory, capable of characterising the viral immune response in greater detail. Such methods need to consider both cellular and humoral immunity. Toward this aim we have investigated use of a commercial multiplex assay (COVID Plus Assay, One Lambda), providing assessment of the SARS-CoV-2 response at structural level, and developed an in-house cell stimulation assay using commercially available viral peptides (Miltenyi). This paper reports our experience in use of these methods in extended investigation of a cohort of healthcare workers with prior screening results indicative of viral infection. The antibody response generated is shown to be both qualitatively and quantitatively different in different individuals. Similarly a recall response to SARS-CoV-2 antigen involving the T cell compartment can be readily demonstrated in recovered individuals but is of variable magnitude.

Management of penicillin allergy in primary care: a qualitative study with patients and primary care physicians

Background

Six percent of patients are allergic to penicillin according to their medical records. While this designation protects a small number of truly allergic patients from serious reactions, those who are incorrectly labelled may be denied access to recommended first line treatment for many infections. Removal of incorrect penicillin allergy may have positive health consequences for the individual and the general population.

We aimed to explore primary care physicians’ (PCPs) and patients’ views and understanding of penicillin allergy with a focus on clinical management of infections in the face of a penicillin allergy record.

Methods

We conducted an interview study with 31 patients with a penicillin allergy record, and 19 PCPs in the North of England. Data were analysed thematically.

Results

Patients made sense of their allergy status by considering the timing and severity of symptoms. Diagnosis of penicillin allergy was reported to be ‘imperfect’ with PCPs relying on patient reports and incomplete medical records. PCPs and patients often suspected that an allergy record was incorrect, but PCPs were reluctant to change records. PCPs had limited knowledge of allergy services. PCPs often prescribed alternative antibiotics which were easy to identify. Both patients and PCPs differed in the extent to which they were aware of the negative consequences of incorrect penicillin allergy records, their relevance and importance to their lives, and management of penicillin allergy.

Conclusions

PCPs and patients appear insufficiently aware of potential harms associated with incorrect penicillin allergy records. Some of the problems experienced by PCPs could be reduced by ensuring the details of newly diagnosed reactions to antibiotics are clearly documented. In order for PCPs to overturn more incorrect penicillin records through appropriate use of allergy services, more information and training about these services will be needed.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12875-021-01465-1.

Mixed results with baricitinib in biological-resistant adult-onset Still's disease and undifferentiated systemic autoinflammatory disease

This clinical case series describes our experience with the use of Janus kinase 1/2 inhibitor baricitinib in two patients suffering from refractory adult-onset Still’s disease (AOSD) as well as in one case suffering from AOSD-like autoinflammatory disease in the context of myelodysplastic syndrome. All patients suffered from disease non-responsive to conventional Disease-modifying antirheumatic drugs (DMARDs) as well as biological therapies including interleukin (IL)-1 and IL-6 blockade, relying instead on high daily doses of prednisolone. We also report the first case of Pneumocystis jirovecii infection following baricitinib use.

OP0057 A PERSONALISED RITUXIMAB RETREATMENT APPROACH BASED ON CLINICAL AND B-CELL BIOMARKERS IN ANCA-ASSOCIATED VASCULITIS

Background:

Time-to-relapse after rituximab for ANCA-associated vasculitis (AAV) is variable and optimal retreatment strategy has been unclear. We previously showed that repopulation of naïve B-cells at 6 months predicts sustained response [1].

Objectives:

In AAV following rituximab induction, to evaluate clinical and B-cell predictors of relapse in order to develop a retreatment algorithm.

Methods:

An observational study was conducted in 60 rituximab-treated AAV patients followed for over 10 years. Complete response (CR) was defined as Birmingham Vasculitis Activity Score v3.0 = 0. Retreatment was given on clinical relapse, defined as new features or worsening of persistent disease (not by biomarker status). Peripheral B-cell subsets were measured using highly sensitive flow cytometry. Predictors were tested using multivariable Cox-Regression.

Results:

Median times-to-retreatment for rituximab cycles 1-5 were 87, 71, 65, 59 and 86 weeks. Over 417 patient-years follow-up, 137 relapses occurred in 50 patients; 16 (in 14 patients) were major (renal=7, neurological=4, ENT=3 and respiratory=2). The major-relapse rate was 3.8/100 patient-years. In multivariable analysis, concomitant immunosuppressant [HR 0.48 (95% CI 0.24–0.94)], achieving CR [0.24 (0.12–0.50)] and naïve B-cell repopulation at 6 months [0.43 (0.22–0.84)] were associated with longer time-to-relapse. Higher baseline memory B-cells [1.01 (1.00–1.02)] were associated with a shorter time-to-relapse. AUROC for prediction of time-to-relapse was greater if guided by naïve B-cell repopulation than if ANCA and/or CD19+ return at 6 months had been used, 0.82 and 0.52 respectively.

Conclusion:

These data suggest that all patients should receive concomitant oral immunosuppressant. Those with incomplete response or with absent naïve B-cells should be retreated at 6 months. Patients with complete response and naïve repopulation at 6 months should not receive fixed retreatment. This algorithm could reduce hypogammaglobulinaemia due to unnecessary retreatment.

Figure 1.

A personalised retreatment algorithm for rituximab in ANCA-associated vasculitis

References:

[1]Md Yusof et al. Annals of rheumatic diseases (2015) PMID: 25854586.

Disclosure of Interests:

Jack Arnold: None declared, Edward Vital Speakers bureau: Roche, GSK and AstraZeneca, Consultant of: Roche, GSK and AstraZeneca, Grant/research support from: Roche, GSK and AstraZeneca, Shouvik Dass Speakers bureau: Roche and GSK, Aamir Aslam: None declared, Andrew Rawstron: None declared, Sinisa Savic: None declared, Paul Emery Speakers bureau: BMS, Abbott, Pfizer, MSD, Novartis, Roche and UCB, Consultant of: BMS, Abbott, Pfizer, MSD, Novartis, Roche and UCB, Grant/research support from: Abbott, BMS, Pfizer, MSD and Roche., Md Yuzaiful Md Yusof: None declared

OP0090 CLASSIFICATION OF PATIENTS WITH RELAPSING POLYCHONDRITIS BASED ON SOMATIC MUTATIONS IN UBA1

Background:

Somatic mutations in ubiquitin activating enzyme 1 (UBA1) cause a newly defined syndrome known as VEXAS. [1] More than fifty percent of patients currently identified with VEXAS meet diagnostic criteria for relapsing polychondritis (RP).

Objectives:

To determine the prevalence VEXAS within a cohort of patients with RP, to compare their clinical, laboratory, and immunologic features and to develop a clinical algorithm to inform genetic screening for VEXAS among patients with RP.

Methods:

Exome and targeted sequencing of the UBA1 gene was performed in a prospective observational cohort of patients with RP. Clinical and immunological characteristics of patients with RP were compared based on presence or absence of UBA1 mutations. Random forest was used to derive a clinical algorithm to identify patients with UBA1 mutations. Immune populations were quantified by multipanel flow cytometry. Categorical and continuous variables were compared using the chi square or Kruskal-Wallis test. P<0.05 defined statistical significance.

Results:

Seven of 92 patients with RP (7.6%) were confirmed to have UBA1 mutations (VEXAS-RP). Six additional patients with VEXAS-RP from other cohorts were included for subsequent analyses. Patients with VEXAS-RP were all male, older at disease onset, and commonly had fever, ear chondritis, skin involvement, deep vein thrombosis, and pulmonary infiltrates. Patients with RP as compared with VEXAS-RP had a significantly higher prevalence of airway chondritis, costochondritis and tenosynovitis/arthralgias. (Table). Mortality was significantly greater in VEXAS-RP than RP (27% vs 2% p=0.01). Maximum ESR, CRP, and mean corpuscular volume (MCV) values were significantly greater in VEXAS-RP. Absolute monocyte, lymphocyte, and platelet counts were significantly lower in VEXAS-RP. A decision tree based on male sex, MCV>100 fl and Platelet count<200 K/ul classified between VEXAS-RP and RP with 100% sensitivity and 96% specificity.

Table 1.

Clinical Characteristics of patients with RP vs VEXAS-RP

All Patientsn=98RPn=85VEXAS-RPn=13p valueDemographic CharacteristicsRace, White n (%)90 (92)77 (91)13 (100)0.59Sex, Male n (%)26 (27)13 (15)13 (100)<0.0001Age, Symptom onset, years, Median (IQR)38 (30-47)37 (28-43)56 (54-64)<0.0001Clinical SymptomsFever n (%)33 (34)20 (24)13 (100)<0.0001Ear chondritis n (%)61 (62)48 (56)13 (100)0.0015Nose chondritis n (%)83 (85)71 (84)12 (92)0.68Airway chondritis n (%)37 (38)37 (44)0 (0)0.0015Tenosynovitis/arthalgias n (%)83 (85)77 (91)6 (46)0.0005Skin involvement n (%)33 (34)22 (2611 (85)<0.0001Laboratory ValuesESR, mm/hr, median (IQR)12 (6-22)11 (5-19)66.5 (42-110)<0.0001CRP, mg/L, median (IQR)2.9 (0.8-9.6)1.9 (0.6-6.3)17.7 (9.6-99.5)<0.0001Platelet count (k/uL)246(201-299)258 (227-312)145 (100-169)<0.0001MCV fL93.05 (90-98)92.2 (89-95)105 (102-115)<0.0001Absolute lymphocyte count1.6 (1.1-2.3)1.78(1.4-2.4)0.92 (0.5-1.2)<0.0001CT scan abnormalitiesPulmonary infiltrates n (%)16 (16.33)6 (7.06)10 (77)<0.0001ComplicationsDeath n (%)6 (6)3 (4)3 (23)0.029Unprovoked DVT12 (12)4 (5)8 (62)<0.0001

N number; IQR = interquartile range

Conclusion:

Mutations in UBA1 are causal for disease in a subset of patients with RP. These patients are defined by disease onset in the fifth decade of life or later, male sex, ear/nose chondritis and hematologic abnormalities. Early identification is important in VEXAS given the associated high mortality rate.

References:

[1]Beck DB, Ferrada MA, Sikora KA, Ombrello AK, Collins JC, Pei W, Balanda N, Ross DL, Ospina Cardona D, Wu Z et al: Somatic Mutations in UBA1 and Severe Adult-Onset Autoinflammatory Disease. N Engl J Med 2020, 383(27):2628-2638.

Disclosure of Interests:

None declared