Developments in the scientific and clinical understanding of autoinflammatory disorders

The autoinflammatory diseases, also known as periodic fever syndromes, are disorders of innate immunity which can be inherited or acquired and which cause recurrent, self-limiting, seemingly spontaneous episodes of systemic inflammation and fever in the absence of autoantibody production or infection. There has been much recent progress in elucidating their aetiologies and treatment. With the exception of familial Mediterranean fever, which is common in certain populations, autoinflammatory diseases are mostly rare but should not be overlooked in the differential diagnosis of recurrent fevers since DNA diagnosis and effective therapies are available for many of them

Pericarditis and Autoinflammation: A Clinical and Genetic Analysis of Patients With Idiopathic Recurrent Pericarditis and Monogenic Autoinflammatory Diseases at a National Referral Center.

Background: Idiopathic recurrent pericarditis (IRP) is an orphan disease that carries significant morbidity, partly driven by corticosteroid dependence. Innate immune modulators, colchicine and anti-interleukin-1 agents, pioneered in monogenic autoinflammatory diseases, have demonstrated remarkable efficacy in trials, suggesting that autoinflammation may contribute to IRP. This study characterizes the phenotype of patients with IRP and monogenic autoinflammatory diseases, and establishes whether autoinflammatory disease genes are associated with IRP. Methods and Results: We retrospectively analyzed the medical records of patients with IRP (n=136) and monogenic autoinflammatory diseases (n=1910) attending a national center (London, UK) between 2000 and 2021. We examined 4 genes (MEFV, MVK, NLRP3, TNFRSF1A) by next-generation sequencing in 128 patients with IRP and compared the frequency of rare deleterious variants to controls obtained from the Genome Aggregation Database. In this cohort of patients with IRP, corticosteroid dependence was common (39/136, 28.7%) and was associated with chronic pain (adjusted odds ratio 2.8 [95% CI, 1.3-6.5], P=0.012). IRP frequently manifested with systemic inflammation (raised C-reactive protein [121/136, 89.0%] and extrapericardial effusions [68/136, 50.0%]). Pericarditis was observed in all examined monogenic autoinflammatory diseases (0.4%-3.7% of cases). Rare deleterious MEFV variants were more frequent in IRP than in ancestry-matched controls (allele frequency 9/200 versus 2932/129 200, P=0.040). Conclusions: Pericarditis is a feature of interleukin-1 driven monogenic autoinflammatory diseases and IRP is associated with variants in MEFV, a gene involved in interleukin-1β processing. We also found that corticosteroid dependence in IRP is associated with chronic noninflammatory pain. Together these data implicate autoinflammation in IRP and support reducing reliance on corticosteroids in its management

Canakinumab treatment for patients with active recurrent or chronic TNF receptor-associated periodic syndrome (TRAPS): An open-label, phase II study

OBJECTIVE: To evaluate the efficacy of canakinumab, a high-affinity human monoclonal anti-interleukin-1β antibody, in inducing complete or almost complete responses in patients with active tumour necrosis factor receptor-associated periodic syndrome (TRAPS). METHODS: Twenty patients (aged 7-78 years) with active recurrent or chronic TRAPS were treated with canakinumab 150 mg every 4 weeks for 4 months (2 mg/kg for those ≤40 kg) in this open-label, proof-of-concept, phase II study. Canakinumab was then withdrawn for up to 5 months, with reintroduction on relapse, and 4 weekly administration (subsequently increased to every 8 weeks) for 24 months. The primary efficacy variable was the proportion of patients achieving complete or almost complete response at day 15, defined as clinical remission (Physician's Global Assessment score ≤1) and full or partial serological remission. RESULTS: Nineteen patients (19/20, 95%; 95% CI 75.1% to 99.9%) achieved the primary efficacy variable. Responses to canakinumab occurred rapidly; median time to clinical remission 4 days (95% CI 3 to 8 days). All patients relapsed after canakinumab was withdrawn; median time to relapse 91.5 days (95% CI 65 to 117 days). On reintroduction of canakinumab, clinical and serological responses were similar to those seen during the first phase, and were sustained throughout treatment. Canakinumab was well tolerated and clinical responses were accompanied by rapid and sustained improvement in health-related quality of life. Weight normalised pharmacokinetics of canakinumab, although limited, appeared to be consistent with historical canakinumab data. CONCLUSIONS: Canakinumab induces rapid disease control in patients with active TRAPS, and clinical benefits are sustained during long-term treatment

IL-36 Promotes Systemic IFN-I Responses in Severe Forms of Psoriasis

Psoriasis is an immune-mediated skin disorder associated with severe systemic comorbidities. Whereas IL-36 is a key disease driver, the pathogenic role of this cytokine has mainly been investigated in skin. Thus, its effects on systemic immunity and extracutaneous disease manifestations remain poorly understood. To address this issue, we investigated the consequences of excessive IL-36 activity in circulating immune cells. We initially focused our attention on generalized pustular psoriasis (GPP), a clinical variant associated with pervasive upregulation of IL-36 signaling. By undertaking blood and neutrophil RNA sequencing, we demonstrated that affected individuals display a prominent IFN-I signature, which correlates with abnormal IL-36 activity. We then validated the association between IL-36 deregulation and IFN-I over-expression in patients with severe psoriasis vulgaris (PV). We also found that the activation of IFN-I genes was associated with extracutaneous morbidity, in both GPP and PV. Finally, we undertook mechanistic experiments, demonstrating that IL-36 acts directly on plasmacytoid dendritic cells, where it potentiates toll-like receptor (TLR)-9 activation and IFN-α production. This effect was mediated by the upregulation of PLSCR1, a phospholipid scramblase mediating endosomal TLR-9 translocation. These findings identify an IL-36/ IFN-I axis contributing to extracutaneous inflammation in psoriasis.</p

Sustained remission of symptoms and improved health-related quality of life in patients with cryopyrin-associated periodic syndrome treated with canakinumab: results of a double-blind placebo-controlled randomized withdrawal study

Abstract Introduction To assess the effect of canakinumab, a fully human anti-interleukin-1β antibody, on symptoms and health-related quality of life (HRQoL) in patients with cryopyrin-associated periodic syndrome (CAPS). Methods In this 48-week, phase 3 study, patients with CAPS received canakinumab 150 mg subcutaneously at 8-week intervals. All patients (n = 35) received canakinumab during weeks 1 through 8; weeks 9 through 24 constituted a double-blind placebo-controlled withdrawal phase, and weeks 24 through 48 constituted an open-label phase in which all patients received canakinumab. Patient and physician assessments of symptoms, levels of inflammatory markers, and HRQoL were performed. Results Rapid symptom remission was achieved, with 89% of patients having no or minimal disease activity on day 8. Responses were sustained in patients receiving 8-weekly canakinumab. Responses were lost during the placebo-controlled phase in the placebo group and were regained on resuming canakinumab therapy in the open-label phase. Clinical responses were accompanied by decreases in serum levels of C-reactive protein, serum amyloid A protein, and interleukin-6. HRQoL scores at baseline were considerably below those of the general population. Improvements in all 36-item Short-Form Health Survey (SF-36) domain scores were evident by day 8. Scores approached or exceeded those of the general U.S. population by week 8 and remained stable during canakinumab therapy. Improvements in bodily pain and role-physical were particularly marked, increasing by more than 25 points from baseline to week 8. Therapy was generally well tolerated. Conclusions Canakinumab, 150 mg, 8-weekly, induced rapid and sustained remission of symptoms in patients with CAPS, accompanied by substantial improvements in HRQoL. Trial registration Clintrials.gov NCT0046598

The experience of hereditary apolipoprotein A-I amyloidosis at the UK National Amyloidosis Centre

INTRODUCTION: Hereditary apolipoprotein A-I (AApoAI) amyloidosis is a rare heterogeneous disease with variable age of onset and organ involvement. There are few series detailing the natural history and outcomes of solid organ transplantation across a range of causative APOA1 gene mutations. METHODS: We identified all patients with AApoAI amyloidosis who presented to the National Amyloidosis Centre (NAC) between 1986 and 2019. RESULTS: In total, 57 patients with 14 different APOA1 mutations were identified including 18 patients who underwent renal transplantation (5 combined liver-kidney (LKT) and 2 combined heart-kidney (HKT) transplants). Median age of presentation was 43 years and median time from presentation to referral was 3 (0-31 years). Involvement of the kidneys, liver and heart by amyloid was detected in 81%, 67% and 28% of patients, respectively. Renal amyloidosis was universal in association with the most commonly identified variant (Gly26Arg, n = 28). Across all variants, patients with renal amyloidosis had a median creatinine of 159 µmol/L and median urinary protein of 0.3 g/24 h at the time of diagnosis of AApoAI amyloidosis and median time from diagnosis to end-stage renal disease was 15.0 (95% CI: 10.0-20.0) years. Post-renal transplantation, median allograft survival was 22.0 (13.0-31.0) years. There was one early death following transplantation (infection-related at 2 months post-renal transplant) and no episodes of early rejection leading to graft failure. Liver transplantation led to regression of amyloid in all four cases in whom serial 123I-SAP scintigraphy was performed. CONCLUSIONS: AApoAI amyloidosis is a slowly progressive disease that is challenging to diagnose. The outcomes of transplantation are encouraging and graft survival is excellent

Prognostic importance of the 6 min walk test in light chain (AL) amyloidosis

OBJECTIVES: In AL amyloidosis, organ response assessment is based on surrogates (eg, cardiac biomarkers). An objective functional test, such as the 6 min walk test (6MWT), capturing overall clinical improvement, is required. We aimed to evaluate the prognostic impact of the 6MWT at baseline and change following chemotherapy. METHODS: This study evaluated the outcomes of patients who enrolled in a prospective observational study at the UK National Amyloidosis Centre (2012-2017). Patients underwent comprehensive assessments inclusive of blood testing, echocardiogram and 6MWT at baseline and annually thereafter. RESULTS: In total, 799 patients were included within the study. Median baseline 6 min walk distance (6MWD) was 362 m (IQR: 231 m). 6MWD progressively decreased with worsening cardiac disease stage (458 m, 404 m, 331 m and 168 m for cardiac Mayo stages I, II, IIIa and IIIb, respectively (p<0.0001)). In patients with a baseline 6MWT of ≥350 m, the median overall survival was not reached (vs 30.0 (95% CI 23.2 to 36.8) months if <350 m and 5.0 (95% CI 2.8 to 7.2) months if unable to attempt 6MWT (p<0.0001). Following chemotherapy, only patients in a complete haematological response improved their 6MWD by 12 months (p=0.001). Improvement in 6MWD prolonged survival in patients with cardiac amyloidosis (p=0.005). CONCLUSION: The 6MWT is prognostic in AL amyloidosis. A baseline distance of ≥350 m independently predicts better survival. These data suggest that 6MWT has utility in AL amyloidosis for baseline prognosis and assessing response