Absence of Pericarditis Recurrence in Rilonacept-Treated Patients With COVID-19 and SARS-CoV-2 Vaccination: Results From the RHAPSODY Long-term Extension.

Background: Rilonacept inhibits the interleukin-1 pathway, and extended treatment in patients with recurrent pericarditis (RP) reduced recurrence risk by 98% in the phase 3 trial, RHAPSODY long-term extension (LTE). Severe acute respiratory syndrome (SARS)-CoV-2 vaccination and/or infection may trigger pericarditis recurrence, and in clinical practice, it is unknown whether to continue rilonacept during SARS-CoV-2 infection. This post-hoc analysis of the RHAPSODY LTE aimed to inform rilonacept management in RP patients vaccinated against SARS-CoV-2 or who contract COVID-19. Methods: Analysis was conducted from May 2020 to June 2022. The LTE portion of RHAPSODY LTE enabled up to 24 months of additional open-label rilonacept treatment beyond the pivotal study. Rilonacept efficacy data in preventing pericarditis recurrence were assessed, and concomitant SARS-CoV-2 vaccination and COVID-19 adverse event data were evaluated. Results: No pericarditis recurrences were temporally associated with vaccination. Sixteen COVID-19 cases were reported; 10 in 30 unvaccinated or partially vaccinated patients (33%) vs 6 of 44 fully vaccinated patients (14%; P = 0.04). Twelve of 16 patients (75%) were receiving rilonacept at the time of infection, and none experienced pericarditis recurrence. One pericarditis recurrence occurred in the peri-COVID-19 period in 1 of 4 patients who had stopped rilonacept treatment > 4.5 months prior. COVID-19 severity was mild in 13 patients, moderate in 2, and severe in 1. Conclusions: Full vaccination effectively reduced COVID-19 events in patients treated with rilonacept. Vaccination or COVID-19 during rilonacept treatment did not increase pericarditis recurrence. Continued rilonacept treatment in patients contracting COVID-19 did not worsen disease severity, whereas rilonacept interruption increased pericarditis recurrence, supporting a recommendation for continued rilonacept treatment for RP during vaccination or COVID-19. ClinicalTrialsgov identifier: NCT03737110.

Contexte: Le rilonacept inhibe la voie de l'interleukine-1 et, d'après les résultats de la période de prolongation à long terme de l'essai de phase III RHAPSODY, la poursuite du traitement par cet agent chez les patients atteints de péricardite récidivante a réduit le risque de récidive de 98 %. La vaccination contre le syndrome respiratoire aigu sévère (SRAS)-CoV-2 ou l'infection à ce virus pourrait toutefois déclencher une récidive de la péricardite, et dans la pratique clinique, on ignore s'il vaut mieux poursuivre le traitement par rilonacept pendant l'infection à SRAS-CoV-2. Cette analyse post-hoc de la période de prolongation à long terme de l'essai RHAPSODY vise à orienter la gestion du rilonacept chez les patients atteints de péricardite récidivante qui sont vaccinés contre le SRAS-CoV-2 ou qui contractent la COVID-19. Méthodologie: L'analyse a été effectuée de mai 2020 à juin 2022. La période de prolongation à long terme de l'essai RHAPSODY a permis d'accumuler des données en mode ouvert pendant une période allant jusqu'à 24 mois au-delà de l'étude pivot. Les données sur l'efficacité du rilonacept en prévention de la récidive de péricardite ont été évaluées, tout comme les données sur la vaccination concomitante contre le SRAS-CoV-2 et les cas de COVID-19. Résultats: Aucune récidive de la péricardite n'a pu être associée sur le plan temporel avec la vaccination. Au total, 16 cas de COVID-19 ont été signalés, dont 10 chez les patients non vaccinés ou partiellement vaccinés sur 30 (33 %) et 6 chez les patients complètement vaccinés sur 44 (14 %; p = 0,04). De ces 16 patients, 12 (75 %) prenaient du rilonacept au moment de l'infection et aucun n'a connu de récidive de la péricardite. Une récidive de la péricardite s'est produite dans la période suivant la COVID-19 chez 1 des 4 patients qui avaient cessé de prendre le rilonacept > 4,5 mois auparavant. La COVID-19 a été légère chez 13 patients, modérée chez 2 patients et sévère chez 1 patient. Conclusions: La vaccination complète a réduit efficacement les cas de COVID-19 chez les patients traités par le rilonacept. La vaccination ou l'infection à SRAS-CoV-2 pendant le traitement par rilonacept n'a pas augmenté le risque de récidive de la péricardite. La poursuite du traitement par rilonacept chez les patients atteints de COVID-19 n'a pas aggravé la sévérité de la maladie, tandis que l'interruption du traitement a augmenté le risque de récidive de la péricardite, ce qui plaide en faveur de la recommandation de poursuivre le traitement de la péricardite récidivante par le rilonacept pendant la vaccination ou la COVID-19. Numéro d'identification ClinicalTrialsgov: NCT03737110.

Sustained Pericarditis Recurrence Risk Reduction With Long-Term Rilonacept.

BACKGROUND: Rilonacept, a once-weekly interleukin-1 alpha and beta cytokine trap, reduced pericarditis recurrence in the phase 3 study, RHAPSODY (Rilonacept Inhibition of Interleukin-1 Alpha and Beta for Recurrent Pericarditis: A Pivotal Symptomatology and Outcomes Study). The RHAPSODY long-term extension further explored recurrent pericarditis natural history and treatment duration decision-making during 24 additional months of open-label rilonacept treatment. METHODS AND RESULTS: Seventy-four patients commenced the long-term extension, with a median (maximum) total rilonacept duration of 22 (35) months. Individually, 18 months after the most proximal pericarditis recurrence, investigators decided to continue rilonacept on study, suspend rilonacept for off-treatment observation (rescue allowed), or discontinue the study. The annualized incidence of pericarditis recurrence on rilonacept up to the 18-month decision milestone was 0.04 events/patient-year versus 4.4 events/patient-year prestudy while on oral therapies. At the 18-month decision milestone, 64% (33/52) continued rilonacept, 15% (8/52) suspended rilonacept for observation, and 21% (11/52) discontinued the study. Among the 33 patients (1/33; 3.0%) continuing rilonacept (median time to recurrence could not be estimated due to too few events), a single recurrence occurred 4 weeks after a treatment interruption. Among patients suspending rilonacept, 75% (6/8) experienced recurrence (median time to recurrence, 11.8 weeks [95% CI, 3.7 weeks to not estimable]). There was a 98% reduction in risk of pericarditis recurrence among patients continuing rilonacept treatment after the 18-month decision milestone versus those suspending treatment for observation (hazard ratio, 0.02; P<0.0001). CONCLUSIONS: In the RHAPSODY long-term extension, continued rilonacept treatment resulted in continued response; treatment suspension at the 18-month decision milestone was associated with pericarditis recurrence. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03737110.

First-in-Human Phase 1 Randomized Trial with the Anti-CD40 Monoclonal Antibody KPL-404: Safety, Tolerability, Receptor Occupancy, and Suppression of T-Cell-Dependent Antibody Response.

Blockade of the cluster of differentiation 40 (CD40)-CD40L interaction has potential for treating autoimmune diseases and preventing graft rejection. This first-in-human, randomized, double-blind, placebo-controlled study (NCT04497662) evaluated safety, pharmacokinetics, receptor occupancy, and pharmacodynamics of the humanized anti-CD40 monoclonal antibody KPL-404. Healthy volunteers were randomized to one of two single-ascending-dose groups: single intravenous KPL-404 dose 0.03, 0.3, 1, 3, or 10 mg/kg or single subcutaneous KPL-404 dose 1 or 5 mg/kg. There were no dose-limiting or dose-related safety findings. Nonlinear dose-dependent changes in various pharmacokinetic parameters were identified following the range of intravenous doses. At the 10 mg/kg intravenous dose level, the t1/2 was approximately 7 days, and full receptor occupancy was observed through Day 71, with complete suppression of T-cell-dependent antibody response (TDAR) to keyhole limpet hemocyanin (KLH) challenge on Day 1 and rechallenge on Day 29 through Day 57. With KPL-404 5 mg/kg subcutaneously, full receptor occupancy was observed through Day 43, with complete suppression of TDAR through at least Day 29. Antidrug antibodies to KPL-404 were suppressed for 57 days with 10 mg/kg intravenously and for 50 days with 5 mg/kg subcutaneously, further confirming prolonged target engagement and pharmacodynamics. These findings support continued investigation of KPL-404 intravenous and subcutaneous administration in a broad range of indications. SIGNIFICANCE STATEMENT: This first-in-human clinical trial of KPL-404, a fully humanized IgG4 monoclonal antibody, was designed with two independent (by route of administration) placebo-controlled single-ascending-dose-level groups, one with four intravenous single-dose cohorts and another with two subcutaneous single-dose cohorts. The pharmacokinetic profile, duration of full CD40 receptor occupancy, and magnitude and duration of memory immune response suppression observed confirm pharmacodynamic activity regardless of administration route. These data provide evidence that chronic KPL-404 dosing regimens (intravenous or subcutaneous) could be practical.

Graft dysfunction in compassionate use of genetically engineered pig-to-human cardiac xenotransplantation: a case report.

BACKGROUND: A genetically engineered pig cardiac xenotransplantation was done on Jan 7, 2022, in a non-ambulatory male patient, aged 57 years, with end-stage heart failure, and on veno-arterial extracorporeal membrane oxygenation support, who was ineligible for an allograft. This report details our current understanding of factors important to the xenotransplantation outcome. METHODS: Physiological and biochemical parameters critical for the care of all heart transplant recipients were collected in extensive clinical monitoring in an intensive care unit. To ascertain the cause of xenograft dysfunction, we did extensive immunological and histopathological studies, including electron microscopy and quantification of porcine cytomegalovirus or porcine roseolovirus (PCMV/PRV) in the xenograft, recipient cells, and tissue by DNA PCR and RNA transcription. We performed intravenous immunoglobulin (IVIG) binding to donor cells and single-cell RNA sequencing of peripheral blood mononuclear cells. FINDINGS: After successful xenotransplantation, the graft functioned well on echocardiography and sustained cardiovascular and other organ systems functions until postoperative day 47 when diastolic heart failure occurred. At postoperative day 50, the endomyocardial biopsy revealed damaged capillaries with interstitial oedema, red cell extravasation, rare thrombotic microangiopathy, and complement deposition. Increased anti-pig xenoantibodies, mainly IgG, were detected after IVIG administration for hypogammaglobulinaemia and during the first plasma exchange. Endomyocardial biopsy on postoperative day 56 showed fibrotic changes consistent with progressive myocardial stiffness. Microbial cell-free DNA testing indicated increasing titres of PCMV/PRV cell-free DNA. Post-mortem single-cell RNA sequencing showed overlapping causes. INTERPRETATION: Hyperacute rejection was avoided. We identified potential mediators of the observed endothelial injury. First, widespread endothelial injury indicates antibody-mediated rejection. Second, IVIG bound strongly to donor endothelium, possibly causing immune activation. Finally, reactivation and replication of latent PCMV/PRV in the xenograft possibly initiated a damaging inflammatory response. The findings point to specific measures to improve xenotransplant outcomes in the future. FUNDING: The University of Maryland School of Medicine, and the University of Maryland Medical Center.

Efficacy and safety of vixarelimab, a human monoclonal oncostatin M receptor ß antibody, in moderate-to-severe prurigo nodularis: a randomised, double-blind, placebo-controlled, phase 2a study.

Background: Prurigo nodularis is a chronic skin disease characterised by intensely pruritic, hyperkeratotic nodules. Vixarelimab, a human monoclonal antibody, binds to the beta subunit of the oncostatin M receptor, inhibiting signalling of both interleukin 31 and oncostatin M, two cytokine pathways that contribute to pruritus and nodule formation in prurigo nodularis. Methods: This double-blind, placebo-controlled, phase 2a trial was done at both private and academic dermatology outpatient research clinics across the United States and Canada (n = 40). Patient eligibility criteria included age 18-75 years, physician-documented diagnosis of prurigo nodularis minimum 6 months duration of prurigo nodularis, presence of at least 10 pruritic nodules approximately 0.5-2 cm in size on at least two different anatomical locations (excluding face and scalp) and involving the extremities, and presence of normal-appearing skin between nodules; atopic dermatitis as a comorbidity was exclusionary. Patients were required to have moderate-to-severe pruritus, defined as Worst Itch-Numeric Rating Scale (WI-NRS) score ≥7 at screening and LS-mean weekly WI-NRS score ≥5 for each of the 2 consecutive weeks immediately before randomisation. Participants were randomly assigned (1:1) to receive weekly subcutaneous vixarelimab 360 mg (720 mg loading dose) or placebo using stratification factors (sex and presence of atopy) and block size 4 through the IWRS system. Stratification by atopy status was based on the reported high prevalence of atopy in this population and the potential impact of atopy in the immunopathologic process in prurigo nodularis. Patients, investigators, study sponsor, and site staff were masked to study treatment. The primary efficacy endpoint was least squares (LS)-mean percent change from baseline (PCFB) at Week 8 in weekly average Worst Itch-Numeric Rating Scale (WI-NRS) score. The primary efficacy endpoint was analysed with ANCOVA including treatment as fixed effect, with baseline WI-NRS, and randomisation stratification factor as covariates. All randomised patients who had at least 1 dose of study drug or placebo were included in the Safety Analysis Set. This trial is registered at ClinicalTrials.gov, NCT03816891. Findings: Of 50 patients randomised between March 11, 2019 and January 31, 2020, 23 vixarelimab recipients and 26 placebo recipients comprised the modified intent-to-treat analysis population (baseline LS-mean [SD] WI-NRS score, 8.3 [1.05]). Outcomes at Week 8 for vixarelimab versus placebo included LS-mean PCFB in WI-NRS score, -50.6% versus -29.4% (LS-mean difference [95% CI], -21.2% [-40.82, -1.60]; p = 0.03); ≥4-point reduction in WI-NRS score, 52.2% (12/23) versus 30.8% (8/26) (p = 0.11); PN-IGA score of 0 or 1, 30.4% (7/23) versus 7.7% (2/26) (p = 0.03); LS-mean PCFB in pruritus VAS score, -54.4% versus -32.6% (p = 0.03); and LS-mean PCFB sleep loss reduction (improvement), -56.3% versus -30.0% (p = 0.02). No deaths, serious TEAEs, or TEAEs leading to dose interruption were reported. The percentage of vixarelimab recipients reporting any TEAE was 91.3% (21/23) versus 76.9% (20/26) of placebo recipients; drug-related TEAEs generally were similar between the two groups (vixarelimab, 43.5% [10/23]; placebo, 38.5% [10/26]). Interpretation: Vixarelimab demonstrated rapid reduction of pruritus and achievement of clear/almost clear skin in one-third of the patients by Week 8. Relief of itch and clearing of skin nodules represent two important potential therapeutic advances in the management of patients suffering from the debilitating disease Prurigo Nodularis. Funding: Kiniksa Pharmaceuticals, Ltd.

Transition to rilonacept monotherapy from oral therapies in patients with recurrent pericarditis.

OBJECTIVE: Polypharmacy management of recurrent pericarditis (RP) often involves long-term therapies, often with negative effects. Slow tapering of oral therapies is often required to avoid recurrence. A post hoc analysis of the phase III trial Rilonacept inHibition of interleukin-1 Alpha and beta for recurrent Pericarditis: a pivotal Symptomatology and Outcomes Study (RHAPSODY) evaluated investigator approaches to transitioning to IL-1 blockade monotherapy with rilonacept, which was hypothesised to allow accelerated withdrawal of common multidrug pericarditis regimens. METHODS: RHAPSODY was a multicentre (Australia, Israel, Italy, USA), double-blind, placebo-controlled, randomised-withdrawal trial in adults and adolescents with RP. Investigators initiated rilonacept at the labelled dose level and discontinued oral pericarditis therapies during the 12-week run-in; randomised patients received study drug as monotherapy. Time to rilonacept monotherapy was quantified in patients receiving multidrug regimens at baseline who achieved rilonacept monotherapy during run-in. RESULTS: In 86 enrolled patients, mean time to rilonacept monotherapy was 7.9 weeks, with no recurrences. Of these, 64% (n=55) entered on multidrug regimens: non-steroidal anti-inflammatory drugs (NSAIDs) plus colchicine (44% (24/55)), colchicine plus glucocorticoids (24% (13/55)), or NSAIDs, colchicine, plus glucocorticoids (33% (18/55)). Investigators transitioned patients receiving colchicine and glucocorticoids at baseline to rilonacept monotherapy without recurrence regardless of taper approach: sequential (n=14; median, 7.7 weeks) or concurrent (n=17; median, 8.0 weeks). Median time to rilonacept monotherapy was similar regardless of glucocorticoid dose and duration: ≤15 mg/day (n=21): 7.3 weeks; >15 mg/day (n=18): 8.0 weeks; long-term (≥28 days): 7.6 weeks. CONCLUSIONS: Rapid discontinuation of oral RP therapies while transitioning to rilonacept monotherapy was feasible without triggering pericarditis recurrence. TRIAL REGISTRATION NUMBER: NCT03737110.

Pericardial late gadolinium enhancement and time to recurrence: a substudy from RHAPSODY, a phase 3 clinical trial of rilonacept in recurrent pericarditis.

Aims: In this protocol-predefined substudy of the RHAPSODY trial, the primary aim was to assess whether pericardial late gadolinium enhancement (LGE) was associated with time to pericarditis recurrence. Methods and results: RHAPSODY was a Phase 3 double-blind, placebo-controlled, randomized-withdrawal trial that demonstrated the efficacy of rilonacept in recurrent pericarditis (RP). Patients with a history of multiple RP and an active recurrence were enrolled and had the option to participate in a cardiac magnetic resonance (CMR) imaging substudy. CMRs were interpreted by a blinded independent core laboratory with prespecified criteria to define pericardial LGE. Compared to patients with trace or mild pericardial LGE (n = 9), patients with moderate or severe pericardial LGE (n = 16) generally had a higher number of recurrent episodes per year (5.3 vs. 3.9) and a higher mean CRP level (3.6 vs. 1.1 mg/dL). Overall, 10/14 (71.4%) who received a placebo had a recurrence compared to 0/11 (0%) who received rilonacept. In patients randomized to placebo who had moderate or severe pericardial LGE, the median time to recurrence was 4.2 weeks compared to 10.7 weeks in patients who had trace or mild pericardial LGE. At the conclusion of the event-driven randomized-withdrawal period, among patients receiving a placebo, 5/7 (71.4%) with trace or mild pericardial LGE and 5/7 (71.4%) with moderate or severe pericardial LGE had a recurrence. Conclusions: Among patients with multiple RP, these preliminary findings support the concept of pericardial LGE as an imaging biomarker that may inform the duration of treatment and risk of recurrence with cessation of therapy and larger studies should be considered. ClinicalTrialsgov Identifier: NCT03737110.

Patients with recurrent pericarditis (RP) can suffer from debilitating pain and a poor quality of life. Rilonacept blocks interleukin 1 (IL-1), the major inflammatory driver of RP, and is highly effective at treating active episodes of RP and preventing recurrence. In pericarditis, there is the recruitment of blood vessels to the pericardium, and the extent of these new blood vessels tracks with the degree of inflammation. Cardiac magnetic resonance imaging (CMR) readily images this blood supply and can therefore assess inflammation by the magnitude of pericardial late gadolinium enhancement (LGE). In this study of RP patients with CMR, no patients who continued rilonacept had a recurrence compared to 10/14 (71.4%) patients who stopped rilonacept and received a placebo. In the patients who received a placebo, the rate of eventual recurrence was similar among patients with trace or mild pericardial LGE at baseline (5/7) compared to patients with moderate or severe pericardial LGE at baseline (5/7). However, patients who demonstrated moderate or severe pericardial LGE had a faster recurrence (∼4 weeks after stopping rilonacept) compared to patients with trace or mild pericardial LGE (∼11 weeks after stopping rilonacept). These results suggest that pericardial LGE can serve as an imaging biomarker to assess the severity of RP and raise the possibility that CMR could be studied in future clinical trials to determine appropriate therapy and treatment duration in patients with RP.

Interleukin-1 Trap Rilonacept Improved Health-Related Quality of Life and Sleep in Patients With Recurrent Pericarditis: Results From the Phase 3 Clinical Trial RHAPSODY.

Background Recurrent pericarditis is characterized by painful flares and inflammation, which negatively impact health-related quality of life. RHAPSODY (rilonacept inhibition of interleukin-1 alpha and beta for recurrent pericarditis: a pivotal symptomatology and outcomes study) evaluated the efficacy and safety of rilonacept (IL-1α and -ß cytokine trap) in recurrent pericarditis. A secondary analysis of these data evaluated the patient-reported outcome questionnaire score change during the trial. Methods and Results Participants completed 5 patient-reported outcome (PRO) questionnaires assessing pericarditis pain, health-related quality of life, general health status, sleep impact, and overall symptom severity. PRO score changes during the treatment run-in period (12 weeks) and the blinded randomized withdrawal period (up to 24 weeks) were evaluated using descriptive statistics and mixed model repeated measures analyses. Participants with PRO data from the run-in period (n=84) and the randomized withdrawal period (n=61; 30 rilonacept, 31 placebo) were included in analyses. Run-in baseline PRO scores indicated that pericarditis symptoms during pericarditis recurrence impacted health-related quality of life. All PRO scores significantly improved (P<0.001) on rilonacept treatment during the run-in period. For the randomized withdrawal period, PRO scores were maintained for participants receiving rilonacept. For those receiving placebo and who experienced a recurrence, PRO scores deteriorated at the time of recurrence and then improved following rilonacept bailout. At randomized withdrawal Week 24/End of Study, scores of participants who received bailout rilonacept were similar to those of participants who had continued rilonacept. Conclusions These results demonstrate the burden of pericarditis recurrences and the improved physical and emotional health of patients with recurrent pericarditis while on rilonacept treatment. These findings extend prior rilonacept efficacy results, demonstrating improvements in patient-reported health-related quality of life, sleep, pain, and global symptom severity while on treatment. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT03737110.

Efficacy and safety of mavrilimumab in giant cell arteritis: a phase 2, randomised, double-blind, placebo-controlled trial.

OBJECTIVES: Granulocyte-macrophage colony-stimulating factor (GM-CSF) is implicated in pathogenesis of giant cell arteritis. We evaluated the efficacy of the GM-CSF receptor antagonist mavrilimumab in maintaining disease remission. METHODS: This phase 2, double-blind, placebo-controlled trial enrolled patients with biopsy-confirmed or imaging-confirmed giant cell arteritis in 50 centres (North America, Europe, Australia). Active disease within 6 weeks of baseline was required for inclusion. Patients in glucocorticoid-induced remission were randomly assigned (3:2 ratio) to mavrilimumab 150 mg or placebo injected subcutaneously every 2 weeks. Both groups received a 26-week prednisone taper. The primary outcome was time to adjudicated flare by week 26. A prespecified secondary efficacy outcome was sustained remission at week 26 by Kaplan-Meier estimation. Safety was also assessed. RESULTS: Of 42 mavrilimumab recipients, flare occurred in 19% (n=8). Of 28 placebo recipients, flare occurred in 46% (n=13). Median time to flare (primary outcome) was 25.1 weeks in the placebo group, but the median was not reached in the mavrilimumab group (HR 0.38; 95% CI 0.15 to 0.92; p=0.026). Sustained remission at week 26 was 83% for mavrilimumab and 50% for placebo recipients (p=0.0038). Adverse events occurred in 78.6% (n=33) of mavrilimumab and 89.3% (n=25) of placebo recipients. No deaths or vision loss occurred in either group. CONCLUSIONS: Mavrilimumab plus 26 weeks of prednisone was superior to placebo plus 26 weeks of prednisone for time to flare by week 26 and sustained remission in patients with giant cell arteritis. Longer treatment is needed to determine response durability and quantify the glucocorticoid-sparing potential of mavrilimumab. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov number: NCT03827018, Europe (EUdraCT number: 2018-001003-36), and Australia (CT-2018-CTN-01 865-1).

Blocking GM-CSF receptor α with mavrilimumab reduces infiltrating cells, pro-inflammatory markers and neoangiogenesis in ex vivo cultured arteries from patients with giant cell arteritis.

BACKGROUND: Effective and safe therapies are needed for the treatment of patients with giant cell arteritis (GCA). Emerging as a key cytokine in inflammation, granulocyte-macrophage colony stimulating factor (GM-CSF) may play a role in promoting inflammation in GCA. OBJECTIVES: To investigate expression of GM-CSF and its receptor in arterial lesions from patients with GCA. To analyse activation of GM-CSF receptor-associated signalling pathways and expression of target genes. To evaluate the effects of blocking GM-CSF receptor α with mavrilimumab in ex vivo cultured arteries from patients with GCA. METHODS: Quantitative real time PCR, in situ RNA hybridisation, immunohistochemistry, immunofluorescence and confocal microscopy, immunoassay, western blot and ex vivo temporal artery culture. RESULTS: GM-CSF and GM-CSF receptor α mRNA and protein were increased in GCA lesions; enhanced JAK2/STAT5A expression/phosphorylation as well as increased expression of target genes CD83 and Spi1/PU.1 were observed. Treatment of ex vivo cultured GCA arteries with mavrilimumab resulted in decreased transcripts of CD3ε, CD20, CD14 and CD16 cell markers, and reduction of infiltrating CD16 and CD3ε cells was observed by immunofluorescence. Mavrilimumab reduced expression of molecules relevant to T cell activation (human leukocyte antigen-DR [HLA-DR]) and Th1 differentiation (interferon-γ), the pro-inflammatory cytokines: interleukin 6 (IL-6), tumour necrosis factor α (TNFα) and IL-1ß, as well as molecules related to vascular injury (matrix metalloprotease 9, lipid peroxidation products and inducible nitric oxide synthase [iNOS]). Mavrilimumab reduced CD34 + cells and neoangiogenesis in GCA lesions. CONCLUSION: The inhibitory effects of mavrilimumab on multiple steps in the GCA pathogenesis cascade in vitro are consistent with the clinical observation of reduced GCA flares in a phase 2 trial and support its development as a therapeutic option for patients with GCA.

Preclinical Immunopharmacologic Assessment of KPL-404, a Novel, Humanized, Non-Depleting Antagonistic Anti-CD40 Monoclonal Antibody.

The CD40/CD40L pathway plays a major role in multiple inflammatory processes involving different immune and stromal cells. Abnormal activation of this pathway has been implicated in pathogenesis of complex autoimmune diseases including systemic lupus erythematosus, rheumatoid arthritis, Graves' disease, and Sjogren's Syndrome. We completed in vitro and in vivo preclinical characterization of KPL-404, a novel humanized anti-CD40 IgG4 monoclonal antibody, to demonstrate its potency, efficacy, and pharmacokinetic profile; safety was also assessed. In vitro, KPL-404 bound recombinant human and cynomolgus monkey CD40 with comparable affinity in the nanomolar range. KPL-404 binding to cell surface CD40 did not induce antibody- or complement-mediated cytotoxicity of CD40-expressing cells. Pharmacological antagonistic activity of KPL-404 was demonstrated in vitro by inhibition of CD40-mediated downstream NF-kB activation. In the in vivo study with cynomolgus monkeys, KPL-404, administered intravenously as a single dose (10 mg/kg) or two monthly doses of 1 or 5 mg/kg, did not elicit observable safety findings, including thrombocytopenia over 8 weeks. KPL-404 engaged CD40 expressed on peripheral B cells for 2 and 4 weeks after a single administration of 5 or 10 mg/kg IV, respectively, without depletion of peripheral B cells. At 5 mg/kg IV, KPL-404 blocked both primary and secondary responses to T-cell dependent antibody responses to test antigens, KLH, and tetanus toxoid. These data illustrated the relationship between KPL-404 serum concentration and pharmacodynamic effects of CD40-targeting in circulation and in lymphoid tissues. These data support clinical development of KPL-404 in autoimmune diseases. SIGNIFICANCE STATEMENT: We aimed to develop a potent and efficacious CD40 antagonist. In vitro and in vivo findings show that KPL-404 blocks the anti-CD40 antibody that potently inhibits primary and secondary antibody responses at pharmacologically relevant concentrations, has a favorable pharmacokinetic profile, and does not deplete B cells by antibody-dependent cellular cytotoxicity or apoptosis ("nondepleting"). These findings support clinical development of KPL-404 as a potential therapeutic in autoimmune diseases.

Disease and Economic Burden Associated with Recurrent Pericarditis in a Privately Insured United States Population.

INTRODUCTION: Approximately 30% of patients with a first acute pericarditis episode experience a recurrence ≤ 18 months; ~ 15% experience multiple recurrences. This study assessed the recurrence and economic burden among patients with multiple recurrences. METHODS: Adults with idiopathic pericarditis were identified in the OptumHealth Care Solutions, Inc., database (2007-2017). Recurrent pericarditis (RP) was defined as ≥ 2 episodes of care separated by > 28 days; multiple recurrences were defined as ≥ 2 recurrences. RESULTS: Among 944 patients with RP, 375 (39.7%) experienced multiple recurrences and were propensity score-matched 1:1 to 375 patients without recurrence. Among patients with multiple recurrences, median disease duration (time from first episode to end of last recurrence, confirmed by a 1.5-year recurrence-free period) was 2.84 years. The multiple recurrences cohort had higher rates of hospitalizations per-patient-per-month (PPPM) than the no recurrence cohort (rate ratio [95% confidence interval (CI)] = 2.22 [1.35-3.65]). Mean total healthcare costs were significantly higher in the multiple recurrences versus no recurrence cohort ($2728 vs. $1568 PPPM, cost ratio [95% CI] = 1.74 [1.29-2.32]), mainly driven by higher hospitalization costs in the multiple recurrences cohort (mean: $1180 vs. $420 PPPM, cost ratio [95% CI] = 2.81 [1.80-4.66]). Mean work loss costs were higher in the multiple recurrences versus no recurrence cohort ($696 vs. $169 PPPM, cost ratio [95% CI] = 4.12 [1.64-9.61]). In patients with multiple recurrences, mean cost of the first episode was $19,189; subsequent recurrences ranged from $2089 to $7366 (second recurrence = $6222). CONCLUSION: In conclusion, among patients with multiple pericarditis recurrences, disease symptoms persisted several years, and healthcare and work loss costs were further compounded in this subset of patients.

Health-related quality of life in patients with recurrent pericarditis: results from a phase 2 study of rilonacept.

BACKGROUND: Impact of recurrent pericarditis (RP) on patient health-related quality of life (HRQoL) was evaluated through qualitative patient interviews and as an exploratory endpoint in a Phase 2 trial evaluating the efficacy and safety of rilonacept (IL-1α/IL-1ß cytokine trap) to treat RP. METHODS: Qualitative interviews were conducted with ten adults with RP to understand symptoms and HRQoL impacts, and the 10-item Patient-Reported Outcomes Measurement Information System Global Health (PROMIS GH) v1.2 was evaluated to determine questionnaire coverage of patient experience. The Phase 2 trial enrolled participants with active symptomatic RP (A-RP, n = 16) and corticosteroid-dependent participants with no active recurrence at baseline (CSD-RP, n = 9). All participants received rilonacept weekly during a 6-week base treatment period (TP) plus an optional 18-week extension period (EP). Tapering of concomitant medications, including corticosteroids (CS), was permitted during EP. HRQoL was assessed using the PROMIS GH, and patient-reported pain and blood levels of c-reactive protein (CRP) were collected at Baseline and follow-up periods. A secondary, descriptive analysis of the Phase 2 trial efficacy results was completed using HRQoL measures to characterize both the impact of RP and the treatment effect of rilonacept. RESULTS: Information from qualitative interviews demonstrated that PROMIS GH concepts are relevant to adults with RP. From the Phase 2 trial, both participant groups showed impacted HRQoL at Baseline (mean PROMIS Global Physical Health [GPH] and Global Mental Health [GMH], were lower than population norm average). In A-RP, GPH/MPH improved by end of base TP and were sustained through EP (similar trends were observed for pain and CRP). Similarly, in CSD-RP, GPH/MPH improved by end of TP and further improved during EP, during CS tapering or discontinuation, without disease recurrence (low pain scores and CRP levels continued during the TP and EP). CONCLUSION: This is the first study demonstrating impaired HRQoL in RP. Rilonacept treatment was associated with HRQoL improvements using PROMIS GH scores. Maintained/improved HRQoL during tapering/withdrawal of CS without recurrence suggests that rilonacept may provide an alternative to CS. TRIAL REGISTRATION: ClinicalTrials.Gov; NCT03980522; 5 June 2019, retrospectively registered; https://clinicaltrials.gov/ct2/show/NCT03980522 .

Prurigo Nodularis Is Characterized by Systemic and Cutaneous T Helper 22 Immune Polarization.

Prurigo nodularis (PN) is an understudied, chronic inflammatory skin disease that disproportionately affects African Americans and presents with intensely pruritic nodules of unknown etiology. To better characterize the immune dysregulation in PN, PBMCs and skin biopsies were obtained from patients with PN and healthy subjects (majority African American) matched by age, race, and sex. Flow cytometric analysis of functional T-cell response comparing patients with PN with healthy subjects identified increased γδT cells (CD3+CD4-CD8-γδTCR+) and Vδ2+ γδT enrichment. Activated T cells demonstrated uniquely increased IL-22 cytokine expression in patients with PN compared with healthy controls. CD4+ and CD8+ T cells were identified as the source of increased circulating IL-22. Consistent with these findings, RNA sequencing of lesional PN skin compared with nonlesional PN skin and biopsy site‒matched control skin demonstrated robust upregulation of T helper (Th) 22‒related genes and signaling networks implicated in impaired epidermal differentiation. Th22‒related cytokine upregulation remained significant, with stratifications by race and biopsy site. Importantly, the expression of the IL-22 receptors IL22RA1 and IL22RA2 was significantly elevated in lesional PN skin. These results indicate that both systemic and cutaneous immune responses in patients with PN are skewed toward a Th22/IL-22 profile. PN may benefit from immunomodulatory therapies directed at Th22‒mediated inflammation.

Mavrilimumab in patients with severe COVID-19 pneumonia and systemic hyperinflammation (MASH-COVID): an investigator initiated, multicentre, double-blind, randomised, placebo-controlled trial.

BACKGROUND: In patients with COVID-19, granulocyte-macrophage colony stimulating factor (GM-CSF) might be a mediator of the hyperactive inflammatory response associated with respiratory failure and death. We aimed to evaluate whether mavrilimumab, a monoclonal antibody to the GM-CSF receptor, would improve outcomes in patients with COVID-19 pneumonia and systemic hyperinflammation. METHODS: This investigator-initiated, multicentre, double-blind, randomised trial was done at seven hospitals in the USA. Inclusion required hospitalisation, COVID-19 pneumonia, hypoxaemia, and a C-reactive protein concentration of more than 5 mg/dL. Patients were excluded if they required mechanical ventilation. Patients were randomly assigned (1:1) centrally, with stratification by hospital site, to receive mavrilimumab 6 mg/kg as a single intravenous infusion, or placebo. Participants and all clinical and research personnel were masked to treatment assignment. The primary endpoint was the proportion of patients alive and off supplemental oxygen therapy at day 14. The primary outcome and safety were analysed in the intention-to-treat population. This trial is registered at ClinicalTrials.gov, NCT04399980, NCT04463004, and NCT04492514. FINDINGS: Between May 28 and Sept 15, 2020, 40 patients were enrolled and randomly assigned to mavrilimumab (n=21) or placebo (n=19). A trial of 60 patients was planned, but given slow enrolment, the study was stopped early to inform the natural history and potential treatment effect. At day 14, 12 (57%) patients in the mavrilimumab group were alive and off supplemental oxygen therapy compared with nine (47%) patients in the placebo group (odds ratio 1·48 [95% CI 0·43-5·16]; p=0·76). There were no treatment-related deaths, and adverse events were similar between groups. INTERPRETATION: There was no significant difference in the proportion of patients alive and off oxygen therapy at day 14, although benefit or harm of mavrilimumab therapy in this patient population remains possible given the wide confidence intervals, and larger trials should be completed. FUNDING: Kiniksa Pharmaceuticals.

The Role of NLRP3 Inflammasome in Pericarditis: Potential for Therapeutic Approaches.

Human samples of patients with chronic pericarditis and appropriate control subjects were stained for the inflammasome components. A mouse model of pericarditis was developed through the intrapericardial injection of zymosan A. Different inflammasome blockers were tested in the mouse model. Patients with pericarditis presented an intensification of the inflammasome activation compared with control subjects. The experimental model showed the pathological features of pericarditis. Among inflammasome blockers, NLRP3 inflammasome inhibitor, anakinra, and interleukin-1 trap were found to significantly improve pericardial alterations. Colchicine partially improved the pericardial inflammation. An intense activation of the inflammasome in pericarditis was demonstrated both in humans and in mice.

Itch intensity in prurigo nodularis is closely related to dermal interleukin-31, oncostatin M, IL-31 receptor alpha and oncostatin M receptor beta.

Prurigo nodularis (PN) is a chronic skin dermatosis with hyperkeratotic and intensely pruritic nodules. Managing PN-associated itch is difficult because its aetiology is still unknown. This study aimed to investigate the correlation between itch intensity in PN and the expression of a pruritogenic cytokine interleukin (IL)-31, its receptor complex components IL-31 receptor α (IL-31RA) and oncostatin M receptor ß (OSMRß), and oncostatin M (OSM), which is a ligand of OSMR ß, through immunofluorescence staining examination. Itch intensity in PN was closely correlated with the number of dermal IL-31(+) cells (Spearman's r = 0.551, p < 0.05), dermal IL-31RA(+) cells (r = 0.475, p < 0.05) and dermal OSM(+) cells (r = 0.505, p < 0.05). In addition, the number of dermal OSMRß (+) cells was increased in PN (t test, p < 0.05), despite not being correlated with itch intensity (Spearman's r = 0.375, p > 0.05). Major cellular sources of dermal IL-31 were T cells (27.0% of total IL-31-expressing cells) and macrophages (35.0%), while those of OSM were mainly T cells (49.8%) and mast cells (26.8%). IL-31RA-expressing dermal cells were mostly mast cells (49.3%) and macrophages (36.6%), and OSMRß was mainly expressed by macrophages (51.8%) in the dermis. These findings indicate that IL-31 (mainly from macrophages and T cells) and OSM (principally from T cells and mast cells) stimulate dermal cells expressing IL-31RA and OSMRß (e.g. macrophages), which may further promote itch and inflammation in PN. This complex dermal milieu of cell/cytokine/receptor network can be a therapeutic target for PN-associated itch.

Phase 3 Trial of Interleukin-1 Trap Rilonacept in Recurrent Pericarditis.

BACKGROUND: Interleukin-1 has been implicated as a mediator of recurrent pericarditis. The efficacy and safety of rilonacept, an interleukin-1α and interleukin-1ß cytokine trap, were studied previously in a phase 2 trial involving patients with recurrent pericarditis. METHODS: We conducted a phase 3 multicenter, double-blind, event-driven, randomized-withdrawal trial of rilonacept in patients with acute symptoms of recurrent pericarditis (as assessed on a patient-reported scale) and systemic inflammation (as shown by an elevated C-reactive protein [CRP] level). Patients presenting with pericarditis recurrence while receiving standard therapy were enrolled in a 12-week run-in period, during which rilonacept was initiated and background medications were discontinued. Patients who had a clinical response (i.e., met prespecified response criteria) were randomly assigned in a 1:1 ratio to receive continued rilonacept monotherapy or placebo, administered subcutaneously once weekly. The primary efficacy end point, assessed with a Cox proportional-hazards model, was the time to the first pericarditis recurrence. Safety was also assessed. RESULTS: A total of 86 patients with pericarditis pain and an elevated CRP level were enrolled in the run-in period. During the run-in period, the median time to resolution or near-resolution of pain was 5 days, and the median time to normalization of the CRP level was 7 days. A total of 61 patients underwent randomization. During the randomized-withdrawal period, there were too few recurrence events in the rilonacept group to allow for the median time to the first adjudicated recurrence to be calculated; the median time to the first adjudicated recurrence in the placebo group was 8.6 weeks (95% confidence interval [CI], 4.0 to 11.7; hazard ratio in a Cox proportional-hazards model, 0.04; 95% CI, 0.01 to 0.18; P<0.001 by the log-rank test). During this period, 2 of 30 patients (7%) in the rilonacept group had a pericarditis recurrence, as compared with 23 of 31 patients (74%) in the placebo group. In the run-in period, 4 patients had adverse events leading to the discontinuation of rilonacept therapy. The most common adverse events with rilonacept were injection-site reactions and upper respiratory tract infections. CONCLUSIONS: Among patients with recurrent pericarditis, rilonacept led to rapid resolution of recurrent pericarditis episodes and to a significantly lower risk of pericarditis recurrence than placebo. (Funded by Kiniksa Pharmaceuticals; RHAPSODY ClinicalTrials.gov number, NCT03737110.).

Efficacy and safety of rilonacept for recurrent pericarditis: results from a phase II clinical trial.

OBJECTIVE: Recurrent pericarditis (RP) incurs significant morbidity. Rilonacept inhibits both interleukin-1 alpha (IL-1α) and IL-1ß; these cytokines are thought to play a major role in RP. This phase II study evaluated rilonacept efficacy and safety in RP. METHODS: This multicentre, open-label study enrolled adult patients with idiopathic or postpericardiotomy RP, symptomatic (≥2 pericarditis recurrences) or corticosteroid (CS) dependent (≥2 recurrences prior).Patients received rilonacept 320 mg SC load/160 mg SC weekly maintenance in a 6-week base treatment period (TP) followed by an optional 18-week on-treatment extension period (EP) (option to wean background therapy). RESULTS: Outcomes: pericarditis pain (numeric rating scale (NRS)) and inflammation (C reactive protein (CRP)) for symptomatic patients; disease activity after CS taper for CS-dependent patients. SECONDARY OUTCOMES: health-related quality of life (HRQOL), pericarditis manifestations and additional medications. 25 unique patients enrolled, while 23 completed the EP (seven colchicine failures and five CS failures). In symptomatic patients, NRS and CRP decreased; response was observed after first rilonacept dose. NRS decreased from 4.5 at baseline to 0.7, and CRP decreased from 4.62 mg/dL at baseline to 0.38 mg/dL at end of TP. Median time to CRP normalisation: 9 days. Pericarditis manifestations resolved. 13 patients on CS at baseline completed the EP; 11 (84.6%) discontinued CS, and 2 tapered; CRP and NRS remained low without recurrence. Mean HRQOL scores improved in symptomatic patients. One serious adverse event (SAE) resulted in discontinuation of rilonacept. CONCLUSIONS: Rilonacept led to rapid and sustained improvement in pain, inflammation (CRP and pericarditis manifestations) and HRQOL. CSs were successfully tapered or discontinued; safety was consistent with known rilonacept safety profile. TRIAL REGISTRATION NUMBER: NCT03980522.