Chimeric antigen receptor T cell therapy for autoimmune disease.

Infusion of T cells engineered to express chimeric antigen receptors (CARs) that target B cells has proven to be a successful treatment for B cell malignancies. This success inspired the development of CAR T cells to selectively deplete or modulate the aberrant immune responses that underlie autoimmune disease. Promising results are emerging from clinical trials of CAR T cells targeting the B cell protein CD19 in patients with B cell-driven autoimmune diseases. Further approaches are being designed to extend the application and improve safety of CAR T cell therapy in the setting of autoimmunity, including the use of chimeric autoantibody receptors to selectively deplete autoantigen-specific B cells and the use of regulatory T cells engineered to express antigen-specific CARs for targeted immune modulation. Here, we highlight important considerations, such as optimal target cell populations, CAR construct design, acceptable toxicities and potential for lasting immune reset, that will inform the eventual safe adoption of CAR T cell therapy for the treatment of autoimmune diseases.

Performance of composite measures used in a trial of etanercept and methotrexate as monotherapy or in combination in psoriatic arthritis.

OBJECTIVES: To examine which composite measures are most sensitive to change when measuring psoriatic arthritis (PsA) disease activity, analyses compared the responsiveness of composite measures used in a 48-week randomized, controlled trial of MTX and etanercept in patients with PsA. METHODS: The trial randomised 851 patients to receive weekly: MTX (20 mg/week), etanercept (50 mg/week) or MTX plus etanercept. Dichotomous composite measures examined included ACR 20/50/70 responses, minimal disease activity (MDA) and very low disease activity (VLDA). Continuous composite measures examined included Disease Activity Score (28 joints) using CRP (DAS28-CRP), Clinical Disease Activity Index (CDAI), Simplified Disease Activity Index (SDAI), Disease Activity for Psoriatic Arthritis (DAPSA) and Psoriatic Arthritis Disease Activity Score (PASDAS). RESULTS: At week 24, etanercept-treated groups were significantly more effective than MTX monotherapy to achieve ACR 20 (primary end point) and MDA (key secondary end point). When examining score changes from baseline at week 24 across the five continuous composite measures, PASDAS demonstrated relatively greater changes in the etanercept-treated groups compared with MTX monotherapy and had the largest effect size and standardized response. Joint count changes drove overall score changes at week 24 from baseline in all the continuous composite measures except for PASDAS, which was driven by the Physician and Patient Global Assessments. CONCLUSION: PASDAS was the most sensitive continuous composite measure examined with results that mirrored the protocol-defined primary and key secondary outcomes. Composite measures with multiple domains, such as PASDAS, may better quantify change in PsA disease burden. TRAIL REGISTRATION: https://ClinicalTrials.gov, number NCT02376790.

Etanercept or Methotrexate Withdrawal in Rheumatoid Arthritis Patients in Sustained Remission.

OBJECTIVE: Patients with rheumatoid arthritis (RA) in whom remission is achieved following combination therapy with methotrexate plus etanercept face an ongoing medication burden. This study was undertaken to investigate whether sustained remission achieved on combination therapy can be maintained with either methotrexate or etanercept monotherapy, as assessed following discontinuation of one or the other medication from the combination. METHODS: Of the 371 adult patients with RA who received combination therapy with methotrexate plus etanercept, remission (defined as a Simplified Disease Activity Index [SDAI] score of ≤3.3) was sustained in 253 patients through a 24-week open-label period. These 253 patients then entered a 48-week, double-blind period and were randomized to receive either 1) methotrexate monotherapy (n = 101), 2) etanercept monotherapy (n = 101), or 3) methotrexate plus etanercept combination therapy (n = 51). Patients who subsequently experienced disease-worsening received rescue therapy with the combination regimen at the same dosages as used in the initial run-in period. The primary end point was the proportion of patients in whom SDAI-defined remission was maintained without disease-worsening at week 48 in the etanercept monotherapy group as compared to the methotrexate monotherapy group. Secondary end points included time to disease-worsening, and the proportion of patients in whom SDAI-defined remission was recaptured after initiation of rescue therapy. RESULTS: Baseline demographic and clinical characteristics of the RA patients were similar across the treatment groups. At week 48, SDAI-defined remission was maintained in significantly more patients in the etanercept monotherapy group than in the methotrexate monotherapy group (49.5% versus 28.7%; P = 0.004). Moreover, as a secondary end point, sustained SDAI-defined remission was achieved in significantly more patients who received combination therapy than in those who received methotrexate monotherapy (52.9% versus 28.7%; P = 0.006). Time to disease-worsening was shorter in those who received methotrexate monotherapy than in those who received etanercept monotherapy or those who received combination therapy (each P < 0.001 versus methotrexate monotherapy). Among the patients who received rescue therapy, SDAI-defined remission was recaptured in 70-80% in each treatment group. No new safety signals were reported. CONCLUSION: The efficacy of etanercept monotherapy was superior to that of methotrexate monotherapy and similar to that of combination therapy in maintaining remission in patients with RA. SDAI-defined remission was recaptured in most of the patients who were given rescue therapy. These data could inform decision-making when withdrawal of therapy is being considered to reduce treatment burden in patients with well-controlled RA.

Measurement properties of the minimal disease activity criteria for psoriatic arthritis.

Objective: To comprehensively assess evidence on the measurement properties of the minimal disease activity (MDA) criteria, a composite measure of the state of disease activity in psoriatic arthritis (PsA). Methods: A targeted literature review was conducted to identify studies that informed the validity and/or ability of the MDA to detect change among patients known to have experienced a change in clinical status. The search was conducted using MEDLINE and Embase databases (published as of October 2017). Pertinent articles provided by investigators and identified from select conference proceedings were also evaluated. Results: A total of 20 publications met the inclusion criteria. The MDA criteria were consistently associated with other indicators of disease activity/severity. The ability of the MDA criteria to detect change was supported in randomised controlled trials (n=10), with a greater percentage of patients randomised to active treatments achieving MDA relative to patients in comparator arms. Long-term observational studies (n=2) provided additional support for the ability of the MDA to detect within-subject change in the real-world settings. Conclusion: Evidence supports the MDA as a valid measure of disease activity in PsA that can detect between-group and within-subject change. The MDA is a comprehensive measure and clinically meaningful endpoint to assess the impact of interventions on PsA disease activity.

Toward Accelerated Authorization and Access to New Medicines for Juvenile Idiopathic Arthritis.

A meeting was organized to bring together multiple stakeholders involved in the testing and authorization of new medications for juvenile idiopathic arthritis (JIA) to discuss current issues surrounding clinical trials and access to new medications for children and adolescents with JIA. The Childhood Arthritis and Rheumatology Research Alliance invited representatives of regulatory agencies (Food and Drug Administration and European Medicines Agency), and major pharmaceutical companies with JIA-approved products or products in development, patient and parent representatives, representatives of an advocacy organization (Arthritis Foundation), and pediatric rheumatology clinicians/investigators to a 1-day meeting in April 2018. The participants engaged in discussion regarding issues in clinical trials. As the pharmacologic options to treat inflammatory arthritis rapidly expand, registration trial designs to test medications in JIA patients must adapt. Many methodologies successfully used in the recent past are no longer feasible. The pool of patients meeting entry criteria who are willing to participate is shrinking while the number of medications to be tested is growing. Suggested solutions included proposing innovative clinical trial methods to regulatory agencies, as well as open discussions among stakeholders. Ensuring that new medications are authorized in a timely manner to meet the needs of JIA patients worldwide is critical. Approaches should include open dialog between regulatory agencies, pharmaceutical companies, and other stakeholders to develop and implement novel study designs, including patient and clinician perspectives to define meaningful trial outcomes, and changing existing study plans.

Decreased Injection Site Pain Associated with Phosphate-Free Etanercept Formulation in Rheumatoid Arthritis or Psoriatic Arthritis Patients: A Randomized Controlled Trial.

INTRODUCTION: Etanercept, a tumor necrosis factor inhibitor, is used to treat rheumatoid arthritis (RA) and psoriatic arthritis (PsA), and is administered via subcutaneous injection. Injection site pain (ISP) associated with subcutaneous administration may affect compliance or hinder initiation of prescribed medications. To improve the patient experience, a new phosphate-free formulation of etanercept was evaluated for reduced ISP associated with administration. METHODS: This phase 3b, multicenter, randomized, double-blind, cross-over study compared the prior formulation of etanercept to a phosphate-free formulation. Etanercept-naïve adults with RA or PsA indicated for treatment with etanercept were eligible. Patients were randomized (1:1) to receive both etanercept formulations (50 mg) in one of two crossover sequences: prior formulation followed by phosphate-free formulation (sequence AB) or phosphate-free formulation followed by prior formulation (sequence BA) at visits 1 week apart. Patients self-reported ISP using a fit-for-purpose 100-mm visual analog scale within 30 s after injection. Safety outcomes included incidence of treatment-emergent adverse events. Mixed-effects analysis of variance model was used to assess ISP, with treatment, study period, sequence, and disease indication as fixed-effect covariates and patient-within-sequence as random effect. RESULTS: A total of 111 patients enrolled (56 sequence AB; 55 sequence BA). Mean ISP score for prior formulation was 23.1 mm and for phosphate-free formulation was 19.1 mm (mean difference - 4 mm; 95% confidence interval: - 8.0, 0.0; P = 0.048). Patients with the highest ISP scores from the prior formulation (by quartile cut points) had the largest reduction in pain with phosphate-free formulation. Injection site reactions were few in number and similar between formulations; no new safety signals were observed. CONCLUSIONS: The new phosphate-free formulation of etanercept had statistically significantly lower mean pain scores than the prior formulation, with largest pain reductions observed among patients who reported highest pain with the prior formulation. TRIAL REGISTRATION: ClinicalTrials.gov: NCT02986139. FUNDING: Amgen Inc, Thousand Oaks, CA USA.

Etanercept and Methotrexate as Monotherapy or in Combination for Psoriatic Arthritis: Primary Results From a Randomized, Controlled Phase III Trial.

OBJECTIVE: To examine the efficacy of methotrexate monotherapy relative to etanercept monotherapy and the value of combining methotrexate and etanercept for the treatment of patients with psoriatic arthritis (PsA). METHODS: In this double-blind study, 851 patients with PsA were randomized to 1 of 3 treatment arms, as follows: oral methotrexate (20 mg) plus subcutaneous placebo given weekly (n = 284), subcutaneous etanercept (50 mg) plus oral placebo given weekly (n = 284), or subcutaneous etanercept (50 mg) plus oral methotrexate (20 mg) given weekly (combination therapy; n = 283). The American College of Rheumatology 20% improvement (ACR20) response and Minimal Disease Activity (MDA) response at week 24 were the primary end point and key secondary end point, respectively. Other measures of inflammatory arthritis, radiographic progression, and nonarticular disease manifestations were also assessed. RESULTS: Patients with PsA had a mean ± SD age of 48.4 ± 13.1 years, and the mean ± SD duration of PsA was 3.2 ± 6.3 years (median 0.6 years). ACR20 and MDA response rates at week 24 were significantly greater in patients who received etanercept monotherapy compared with those who received methotrexate monotherapy (ACR20, 60.9% versus 50.7% of patients [P = 0.029]; MDA, 35.9% versus 22.9% of patients [P = 0.005]), and both were significantly greater in the combination therapy group compared with the methotrexate monotherapy group at week 24 (ACR20, 65.0% versus 50.7% of patients [P = 0.005]; MDA, 35.7% versus 22.9% of patients [P = 0.005]). Other secondary outcomes (ACR50 and ACR70 response rates, proportions of patients achieving a Very Low Disease Activity score, and PsA disease activity scores) showed between-group differences that were consistent with the primary and key secondary end point results. Furthermore, patients in both etanercept treatment arms showed less radiographic progression at week 48 compared with patients who received methotrexate monotherapy. Outcomes were similar in the combination therapy and etanercept monotherapy groups, except for some skin end points. No new safety signals were seen. CONCLUSION: Etanercept monotherapy and combination therapy with etanercept and methotrexate showed greater efficacy than methotrexate monotherapy in patients with PsA, according to the ACR and MDA response rates and extent of radiographic progression at follow-up. Overall, combining methotrexate and etanercept did not improve the efficacy of etanercept.

Open-Label Study to Evaluate the Efficacy of Etanercept Treatment in Subjects With Moderate to Severe Plaque Psoriasis Who Have Failed Therapy With Apremilast.

INTRODUCTION: Response to etanercept therapy in patients who have failed apremilast therapy has not been well characterized. METHODS: In this multicenter, open-label, single-arm, phase 4, estimation study, subjects with moderate to severe plaque psoriasis received etanercept 50 mg SC twice weekly for 12 weeks, followed by etanercept 50 mg SC once weekly for an additional 12 weeks. Subjects had BSA greater than equal to 10%, PASI greater than equal to 10, and sPGA greater than equal to 3 at screening and baseline; and had failed apremilast-because of either failure to achieve or loss of adequate clinical response, or intolerability to apremilast in the opinion of the investigator. Primary endpoint was PASI 75 at week 12. Secondary endpoints included PASI 75 at week 24, PASI 90 at weeks 12 and 24, and patient-reported outcomes: Psoriasis Symptom Inventory (PSI) score (total and individual items) at baseline and weeks 12 and 24, and over time; DLQI responder analysis (5-point improvement in DLQI from baseline or score of 0) at weeks 12 and 24; and patient assessment of treatment satisfaction at baseline and weeks 12 and 24. RESULTS: Among 80 patients, PASI 75 at weeks 12 and 24 was 41.6% (95% CI, 30.4%-53.4%) and 45.5% (34.1%-57.1%), respectively; PASI 90 was 13.0% (6.4%-22.6%) and 22.1% (13.4%-33.0%), respectively. Mean total PSI score (LOCF) improved from 16.6 (95% CI, 15.1-18.0) at baseline to 8.8 (7.3-10.2) and 9.6 (7.9-11.4) at weeks 12 and 24, respectively; improvements in item PSI scores were similar. The percentage of DLQI responders was 66.2% (95% CI, 54.3%-76.8%) and 57.3% (45.4%-68.7%) at weeks 12 and 24, respectively. The percentage of subjects who were satisfied/very satisfied with their psoriasis treatment improved from 5.0% at baseline to 60.8% and 53.3% at weeks 12 and 24, respectively. During the 24-week study, 23.8% and 2.5% of subjects reported an adverse event and serious adverse event, respectively; there were no new safety signals in this study. DISCUSSION: In patients who have failed apremilast, etanercept may represent an effective therapeutic option. TRIAL REGISTRATION: ClinicalTrials.gov: NCT02749370 J Drugs Dermatol. 2018;17(10):1078-1082.

Design and rationale of the Study of Etanercept and Methotrexate in Combination or as Monotherapy in Subjects with Psoriatic Arthritis (SEAM-PsA).

OBJECTIVE: To evaluate the efficacy of etanercept and methotrexate as monotherapies and as combination therapy in subjects with active psoriatic arthritis (PsA). METHODS: The Study of Etanercept and Methotrexate in Combination or as Monotherapy in Subjects with Psoriatic Arthritis (SEAM-PsA) is an ongoing, global, double-blind, 48-week, randomised, controlled study. Subjects are randomised (1:1:1) to etanercept monotherapy, methotrexate monotherapy or etanercept-methotrexate combination therapy. Endpoints include rates of ACR20 response and Minimal Disease Activity, measures to characterise extra-articular manifestations (dactylitis, enthesitis, nail disease) and safety. CONCLUSION: SEAM-PsA will characterise the effects of etanercept with and without background methotrexate and methotrexate alone on PsA manifestations, and provide information of practical importance to clinicians on the optimal treatment of PsA.

Brief Report: A Randomized, Double-Blind, Parallel-Group, Placebo-Controlled, Multiple-Dose Study to Evaluate AMG 557 in Patients With Systemic Lupus Erythematosus and Active Lupus Arthritis.

OBJECTIVE: To evaluate the safety and potential efficacy of AMG 557, a fully human antibody directed against the inducible T cell costimulator ligand (ICOSL) in patients with systemic lupus erythematosus (SLE) with arthritis. METHODS: In this phase Ib, randomized, double-blind, placebo-controlled study, patients received AMG 557 210 mg (n = 10) or placebo (n = 10) weekly for 3 weeks, then every other week for 10 additional doses. The corticosteroid dosage was tapered to ≤7.5 mg/day by day 85, and immunosuppressants were discontinued by day 29. Primary end points on day 169 were safety, immunogenicity, the Lupus Arthritis Response Index (LARI; defined by a reduction in the tender and swollen joint counts), ≥1-letter improvement in the musculoskeletal domain of the British Isles Lupus Assessment Group (BILAG) index, and medication discontinuation. The secondary/exploratory end points were changes in the tender and swollen joint counts, BILAG index scores (musculoskeletal, global), and the Systemic Lupus Erythematosus Disease Activity Index (SLEDAI). RESULTS: The incidence of adverse events, most of which were mild, was similar between groups. LARI responses occurred in 3 of 10 patients receiving AMG 557 and 1 of 10 patients receiving placebo (P = 0.58). More patients in the AMG 557 group achieved a ≥4-point improvement in the SLEDAI score on day 169 (7 of 10 patients) compared with the placebo group (2 of 10 patients) (P = 0.07). Patients treated with AMG 557 (versus placebo) had greater improvements from baseline in the global BILAG index scores (-36.3% versus -24.7%) and the SLEDAI score (-47.8% versus -10.7%) and in tender (-22.8% versus -13.5%) and swollen (-62.1% versus -7.8%) joint counts on day 169. CONCLUSION: AMG 557 showed safety and potential efficacy, supporting further evaluation of the clinical efficacy of ICOSL blockade in patients with SLE.

Safety, pharmacokinetics and pharmacodynamics of AMG 811, an anti-interferon-γ monoclonal antibody, in SLE subjects without or with lupus nephritis.

OBJECTIVE: To evaluate safety, pharmacokinetics and pharmacodynamics of anti-interferon (IFN)-γ monoclonal antibody AMG 811 in subjects with SLE without or with lupus nephritis (LN). METHODS: In this phase Ib, randomised, multiple-dose escalation study (NCT00818948), subjects without LN were randomised to subcutaneous AMG 811 (6, 20 or 60 mg) or placebo and subjects with LN were randomised to subcutaneous AMG 811 (20, 60 or 120 mg) or placebo every four weeks for three total doses. Outcomes included incidence of adverse events (AEs); pharmacokinetics; levels of serum proteins (CXCL-10, interleukin 18, monocyte chemotactic protein-1); changes in gene transcript profiles and clinical parameters (Safety of Estrogen in Lupus Erythematosus National Assessment-Systemic Lupus Erythematosus Disease Activity Index (SELENA-SLEDAI) scores, proteinuria, anti-double-stranded DNA (anti-dsDNA) antibodies, C3 complement, C4 complement). RESULTS: Fifty-six subjects enrolled (28 SLE without LN; 28 with LN). Baseline mean SELENA-SLEDAI scores were 2.2 and 12.0 for SLE subjects without and with LN, respectively. Most subjects reported an AE; no meaningful imbalances were observed between AMG 811 and placebo. Pharmacokinetic profiles were similar and mostly dose-proportional in subjects without or with LN. AMG 811 treatment reduced CXCL-10 protein levels and blood-based RNA IFN-γ Blockade Signature compared with placebo. Reductions were less pronounced and not sustained in subjects with LN, even at the highest dose tested, compared with subjects without LN. No effect on SELENA-SLEDAI scores, proteinuria, C3 or C4 complement levels, or anti-dsDNA antibodies was observed. CONCLUSION: AMG 811 demonstrated favourable pharmacokinetics and acceptable safety profile but no evidence of clinical impact. IFN-γ-associated biomarkers decreased with AMG 811; effects were less pronounced and not sustained in LN subjects. TRIAL REGISTRATION NUMBER: NCT00818948; results.

Retrospective analysis to describe associations between tumor necrosis factor alpha inhibitors and COPD-related hospitalizations.

BACKGROUND: Limited information exists on the impact of tumor necrosis factor inhibition on COPD exacerbations. This retrospective study characterized this impact among COPD patients with underlying autoimmune conditions, exposed to tumor necrosis factor inhibitors (TNFi) and/or non-biologic disease-modifying antirheumatic drugs (DMARDs). PATIENTS AND METHODS: Adult COPD patients with ≥1 diagnosis for rheumatoid arthritis (RA), psoriasis (PsO), psoriatic arthritis (PsA), or ankylosing spondylitis (AS) before or within 6 months following the index COPD diagnosis were identified from the Truven Health MarketScan® databases. Patients were required to have a second claim for RA, PsO, PsA, AS, or DMARD use (biologic or non-biologic) prior to or up to 6 months following the index date. Incidence of COPD-related hospitalizations and emergency room (ER) visits was evaluated in relation to treatment with TNFi and/or DMARDs and other potential risk factors. RESULTS: The study cohort included 40,687 patients (untreated, 37.7%; non-biologic DMARD, 35.4%; TNFi + non-biologic DMARD, 18%; TNFi, 8.8%). The proportion of patients with a COPD-related hospitalization and the incidence of COPD-related hospitalization (per 100 person-years) were lowest in the TNFi cohort (8.6%; 3.54, 95% confidence interval [CI]: 3.16-3.95) and the TNFi + non-biologic DMARD cohort (8.4%; 2.85, 95% CI: 2.63-3.08). In multivariate models, treatment with TNFi + non-biologic DMARD reduced the risk of COPD-related hospitalization or ER visits by 32% relative to non-biologic DMARDs (hazard ratio: 0.68; 95% CI: 0.61-0.75). CONCLUSION: In real-world settings, TNFi monotherapy confers similar risk for COPD-related hospitalization or ER visits as a non-biologic DMARD. Decreased risk was found among those treated with both TNFi and a non-biologic DMARD.

Brief Report: Pharmacodynamics, Safety, and Clinical Efficacy of AMG 811, a Human Anti-Interferon-γ Antibody, in Patients With Discoid Lupus Erythematosus.

OBJECTIVE: Interferon-γ (IFNγ) is implicated in the pathogenesis of discoid lupus erythematosus (DLE). This study sought to evaluate a single dose of AMG 811, an anti-IFNγ antibody, in patients with DLE. METHODS: The study was designed as a phase I randomized, double-blind, placebo-controlled crossover study of the pharmacodynamics, safety, and clinical efficacy of AMG 811 in patients with DLE. Patients received a single subcutaneous dose of AMG 811 (180 mg) or placebo. The patients in sequence 1 received AMG 811 followed by placebo, while those in sequence 2 received placebo followed by AMG 811. Pharmacodynamic end points included global transcriptional analyses of lesional and nonlesional skin, IFNγ blockade signature (IGBS) transcriptional scores in the skin and blood, keratinocyte IFNγ RNA scores, and serum levels of CXCL10 protein. Additional end points were efficacy outcome measures, including the Cutaneous Lupus Erythematosus Disease Area and Severity Index, and safety outcome measures. RESULTS: Sixteen patients with DLE were enrolled in the study (9 in sequence 1 and 7 in sequence 2). AMG 811 treatment reduced the IGBS score (which was elevated in DLE patients at baseline) in both the blood and lesional skin. The keratinocyte IFNγ RNA score was not affected by administration of AMG 811. Serum CXCL10 protein levels (which were elevated in the blood of DLE patients) were reduced with AMG 811 treatment. The AMG 811 treatment was well tolerated but did not lead to statistically significant improvements in any of the efficacy outcome measures. CONCLUSION: AMG 811 treatment led to changes in IFNγ-associated biomarkers and was well tolerated, but no significant clinical benefit was observed in patients with DLE.

Blockade of interferon-γ normalizes interferon-regulated gene expression and serum CXCL10 levels in patients with systemic lupus erythematosus.

OBJECTIVE: To assess the safety and immunologic impact of inhibiting interferon-γ (IFNγ) with AMG 811, a human IgG1 monoclonal antibody against IFNγ, in patients with systemic lupus erythematosus (SLE). METHODS: Twenty-six patients with mild-to-moderate, stable SLE were administered placebo or a single dose of AMG 811, ranging from 2 mg to 180 mg subcutaneously or 60 mg intravenously. RESULTS: Similar to results previously reported following inhibition of type I IFNs, treatment of SLE patients with AMG 811 led to a dose-dependent modulation of the expression of genes associated with IFN signaling, as assessed by microarray analysis of the whole blood. The list of impacted genes overlapped with that identified by stimulating human whole blood with IFNγ and with those gene sets reported in the literature to be differentially expressed in SLE patients. Serum levels of IFNγ-induced chemokines, including IFNγ-inducible protein 10 (IP-10), were found to be elevated at baseline in SLE patients as compared to healthy volunteers. In contrast to previously reported results from studies using type I IFN-blocking agents, treatment with AMG 811 led to dose-related reductions in the serum levels of CXCL10 (IP-10). CONCLUSION: The scope and nature of the biomarkers impacted by AMG 811 support targeting of IFNγ as a therapeutic strategy for SLE.

A phase Ib multiple ascending dose study evaluating safety, pharmacokinetics, and early clinical response of brodalumab, a human anti-IL-17R antibody, in methotrexate-resistant rheumatoid arthritis.

INTRODUCTION: The aim of this study was to evaluate the safety, pharmacokinetics, and clinical response of brodalumab (AMG 827), a human, anti-IL-17 receptor A (IL-17RA) monoclonal antibody in subjects with moderate-to-severe rheumatoid arthritis (RA). METHODS: This phase Ib, randomized, placebo-controlled, double-blind multiple ascending dose study enrolled subjects with moderate to severe RA (≥ 6/66 swollen and ≥ 8/68 tender joints). Subjects were randomized 3:1 to receive brodalumab (50 mg, 140 mg, or 210 mg subcutaneously every two weeks for 6 doses per group; or 420 mg or 700 mg intravenously every 4 weeks for two doses per group) or placebo. Endpoints included incidence of adverse events (AEs) and pharmacokinetics. Exploratory endpoints included pharmacodynamics, and improvements in RA clinical metrics. RESULTS: Forty subjects were randomized to investigational product; one subject discontinued due to worsening of RA (placebo). The study was not designed to assess efficacy. AEs were reported by 70% (7/10) of placebo subjects and 77% (22/30) of brodalumab subjects. Three serious AEs were reported in two subjects; there were no opportunistic infections. Brodalumab treatment resulted in inhibition of IL-17 receptor signaling and receptor occupancy on circulating leukocytes. No treatment effects were observed with individual measures of RA disease activity. On day 85 (week 13) 37% (11/30) of brodalumab subjects and 22% (2/9) of placebo subjects achieved ACR20; 7% (2/30) brodalumab subjects and 11% (1/9) of placebo subjects achieved ACR50; and 0% (0/30) brodalumab subjects and 0% (0/9) of placebo subjects achieved ACR70. CONCLUSIONS: Multiple dose administration of brodalumab was tolerated in subjects with active RA. There was no evidence of a clinical response to brodalumab in subjects with RA. TRIAL REGISTRATION: ClinicalTrials.gov, NCT00771030.

Incomplete activation of CD4 T cells by antigen-presenting transitional immature B cells: implications for peripheral B and T cell responsiveness.

B cells leave the bone marrow as transitional B cells. Transitional B cells represent a target of negative selection and peripheral tolerance, both of which are abrogated in vitro by mediators of T cell help. In vitro, transitional and mature B cells differ in their responses to B cell receptor ligation. Whereas mature B cells up-regulate the T cell costimulatory molecule CD86 (B7.2) and are activated, transitional B cells do not and undergo apoptosis. The ability of transitional B cells to process and present Ag to CD4 T cells and to elicit protective signals in the absence of CD86 up-regulation was investigated. We report that transitional B cells can process and present Ag as peptide:MHC class II complexes. However, their ability to activate T cells and elicit help signals from CD4-expressing Th cells was compromised compared with mature B cells, unless exogenous T cell costimulation was provided. A stringent requirement for CD28 costimulation was not evident in interactions between transitional B cells and preactivated CD4-expressing T cells, indicating that T cells involved in vivo in an ongoing immune response might rescue Ag-specific transitional B cells from negative selection. These data suggest that during an immune response, immature B cells may be able to sustain the responses of preactivated CD4(+) T cells, while being unable to initiate activation of naive T cells. Furthermore, the ability of preactivated, but not naive T cells to provide survival signals to B cell receptor-engaged transitional immature B cells argues that these B cells may be directed toward activation rather than negative selection when encountering Ag in the context of a pre-existing immune response.

Transitional B cells: step by step towards immune competence.

Transitional B cells mark the crucial link between bone-marrow (BM) immature and peripheral mature B cells. Examination reveals unexpected heterogeneity, consisting of contiguous subsets with phenotypic and functional differences. Data point to the late transitional B-cell stage as a crucial juncture at which developing B cells gain access to splenic follicles, become responsive to T-cell help and lose sensitivity to negative selection, characterizing the immature B-cell response to B-cell antigen receptor (BCR) signaling in vitro and in vivo. The biological and molecular processes directing maturation through this stage are becoming clearer through biochemical studies and murine models deficient in various components of the BCR signaling pathway.