Christopher T. Ritchlin

Mechanisms of TNF-α– and RANKL-mediated osteoclastogenesis and bone resorption in psoriatic arthritis

Psoriatic arthritis (PsA) is an inflammatory joint disease characterized by extensive bone resorption. The mechanisms underlying this matrix loss have not been elucidated. We report here that blood samples from PsA patients, particularly those with bone erosions visible on plain radiographs, exhibit a marked increase in osteoclast precursors (OCPs) compared with those from healthy controls. Moreover, PsA PBMCs readily formed osteoclasts in vitro without exogenous receptor activator of NF-kappaB ligand (RANKL) or MCSF. Both osteoprotegerin (OPG) and anti-TNF antibodies inhibited osteoclast formation. Additionally, cultured PsA PBMCs spontaneously secreted higher levels of TNF-alpha than did healthy controls. In vivo, OCP frequency declined substantially in PsA patients following treatment with anti-TNF agents. Immunohistochemical analysis of subchondral bone and synovium revealed RANK-positive perivascular mononuclear cells and osteoclasts in PsA specimens. RANKL expression was dramatically upregulated in the synovial lining layer, while OPG immunostaining was restricted to the endothelium. These results suggest a model for understanding the pathogenesis of aggressive bone erosions in PsA. OCPs arise from TNF-alpha-activated PBMCs that migrate to the inflamed synovium and subchondral bone, where they are exposed to unopposed RANKL and TNF-alpha. This leads to osteoclastogenesis at the erosion front and in subchondral bone, resulting in a bidirectional assault on psoriatic bone.

European League Against Rheumatism recommendations for the management of psoriatic arthritis with pharmacological therapies

Background Psoriatic arthritis (PsA) is a clinically heterogeneous disease. Clear consensual treatment guidance focused on the musculoskeletal manifestations of PsA would be advantageous. The authors present European League Against Rheumatism (EULAR) recommendations for the treatment of PsA with systemic or local (non-topical) symptomatic and disease-modifying antirheumatic drugs (DMARD). Methods The recommendations are based on evidence from systematic literature reviews performed for non-steroidal anti-inflammatory drugs (NSAID), glucocorticoids, synthetic DMARD and biological DMARD. This evidence was discussed, summarised and recommendations were formulated by a task force comprising 35 representatives, and providing levels of evidence, strength of recommendations and levels of agreement. Results Ten recommendations were developed for treatment from NSAID through synthetic DMARD to biological agents, accounting for articular and extra-articular manifestations of PsA. Five overarching principles and a research agenda were defined. Conclusion These recommendations are intended to provide rheumatologists, patients and other stakeholders with a consensus on the pharmacological treatment of PsA and strategies to reach optimal outcomes, based on combining evidence and expert opinion. The research agenda informs directions within EULAR and other communities interested in PsA.

Treatment recommendations for psoriatic arthritis

Objective: To develop comprehensive recommendations for the treatment of the various clinical manifestations of psoriatic arthritis (PsA) based on evidence obtained from a systematic review of the literature and from consensus opinion. Methods: Formal literature reviews of treatment for the most significant discrete clinical manifestations of PsA (skin and nails, peripheral arthritis, axial disease, dactylitis and enthesitis) were performed and published by members of the Group for Research and Assessment of Psoriasis and Psoriatic Arthritis (GRAPPA). Treatment recommendations were drafted for each of the clinical manifestations by rheumatologists, dermatologists and PsA patients based on the literature reviews and consensus opinion. The level of agreement for the individual treatment recommendations among GRAPPA members was assessed with an online questionnaire. Results: Treatment recommendations were developed for peripheral arthritis, axial disease, psoriasis, nail disease, dactylitis and enthesitis in the setting of PsA. In rotal, 19 recommendations were drafted, and over 80% agreement was obtained on 16 of them. In addition, a grid that factors disease severity into each of the different disease manifestations was developed to help the clinician with treatment decisions for the individual patient from an evidenced-based perspective. Conclusions: Treatment recommendations for the cardinal physical manifestations of PsA were developed based on a literature review and consensus between rheumatologists and dermatologists. In addition, a grid was established to assist in therapeutic reasoning and decision making for individual patients. It is anticipated that periodic updates will take place using this framework as new data become available.

Efficacy and safety of ustekinumab in patients with active psoriatic arthritis: 1 year results of the phase 3, multicentre, double-blind, placebo-controlled PSUMMIT 1 trial

BACKGROUND Many patients with psoriasis develop psoriatic arthritis, a chronic inflammatory disease that afflicts peripheral synovial, axial, and entheseal structures. The fully human monoclonal antibody ustekinumab is an efficacious treatment for moderate-to-severe plaque psoriasis. We did a randomised, placebo-controlled, phase 3 trial to assess the safety and efficacy of ustekinumab in patients with active psoriatic arthritis. METHODS In this phase 3, multicentre, double-blind, placebo-controlled trial at 104 sites in Europe, North America, and Asia-Pacific, adults with active psoriatic arthritis (≥5 tender and ≥5 swollen joints, C-reactive protein ≥3·0 mg/L) were randomly assigned (1:1:1, by dynamic central randomisation based on an algorithm implemented by an interactive voice-web response system) to 45 mg ustekinumab, 90 mg ustekinumab, or placebo at week 0, week 4, and every 12 weeks thereafter. At week 16, patients with less than 5% improvement in both tender and swollen joint counts entered masked early-escape and were given 45 mg ustekinumab (if in the placebo group) or 90 mg ustekinumab (if in the 45 mg group). At week 24, all remaining patients in the placebo group received ustekinumab 45 mg, which they continued at week 28 and every 12 weeks thereafter. Our primary endpoint was 20% or greater improvement in American College of Rheumatology (ACR20) criteria at week 24. This trial is registered with ClinicalTrials.gov (NCT01009086) and EudraCT (2009-012264-14). FINDINGS Between Nov 30, 2009, and March 30, 2011, 615 patients were randomly assigned-206 to placebo, 205 to 45 mg ustekinumab, and 204 to 90 mg ustekinumab. More ustekinumab-treated (87 of 205 [42·4%] in the 45 mg group and 101 of 204 [49·5%] in the 90 mg group) than placebo-treated (47 of 206 [22·8%]) patients achieved ACR20 at week 24 (p<0·0001 for both comparisons); responses were maintained at week 52. At week 16, proportions of patients with adverse events were similar in the ustekinumab and placebo groups (171 of 409 [41·8%] vs 86 of 205 [42·0%]). INTERPRETATION Ustekinumab significantly improved active psoriatic arthritis compared with placebo, and might offer an alternative therapeutic mechanism of action to approved biological treatments. FUNDING Janssen Research & Development.

Efficacy and safety of the anti-IL-12/23 p40 monoclonal antibody, ustekinumab, in patients with active psoriatic arthritis despite conventional non-biological and biological anti-tumour necrosis factor therapy: 6-month and 1-year results of the phase 3, multicentre, double-blind, placebo- controlled, randomised PSUMMIT 2 trial

Objective Assess ustekinumab efficacy (week 24/week 52) and safety (week 16/week 24/week 60) in patients with active psoriatic arthritis (PsA) despite treatment with conventional and/or biological anti-tumour necrosis factor (TNF) agents. Methods In this phase 3, multicentre, placebo-controlled trial, 312 adults with active PsA were randomised (stratified by site, weight (≤100 kg/>100 kg), methotrexate use) to ustekinumab 45 mg or 90 mg at week 0, week 4, q12 weeks or placebo at week 0, week 4, week 16 and crossover to ustekinumab 45 mg at week 24, week 28 and week 40. At week 16, patients with <5% improvement in tender/swollen joint counts entered blinded early escape (placebo→45 mg, 45 mg→90 mg, 90 mg→90 mg). The primary endpoint was ≥20% improvement in American College of Rheumatology (ACR20) criteria at week 24. Secondary endpoints included week 24 Health Assessment Questionnaire-Disability Index (HAQ-DI) improvement, ACR50, ACR70 and ≥75% improvement in Psoriasis Area and Severity Index (PASI75). Efficacy was assessed in all patients, anti-TNF-naïve (n=132) patients and anti-TNF-experienced (n=180) patients. Results More ustekinumab-treated (43.8% combined) than placebo-treated (20.2%) patients achieved ACR20 at week 24 (p<0.001). Significant treatment differences were observed for week 24 HAQ-DI improvement (p<0.001), ACR50 (p≤0.05) and PASI75 (p<0.001); all benefits were sustained through week 52. Among patients previously treated with ≥1 TNF inhibitor, sustained ustekinumab efficacy was also observed (week 24 combined vs placebo: ACR20 35.6% vs 14.5%, PASI75 47.1% vs 2.0%, median HAQ-DI change −0.13 vs 0.0; week 52 ustekinumab-treated: ACR20 38.9%, PASI75 43.4%, median HAQ-DI change −0.13). No unexpected adverse events were observed through week 60. Conclusions The interleukin-12/23 inhibitor ustekinumab (45/90 mg q12 weeks) yielded significant and sustained improvements in PsA signs/symptoms in a diverse population of patients with active PsA, including anti-TNF-experienced PsA patients.

Secukinumab, a human anti-interleukin-17A monoclonal antibody, in patients with psoriatic arthritis (FUTURE 2): a randomised, double-blind, placebo-controlled, phase 3 trial.

BACKGROUND Interleukin 17A is a proinflammatory cytokine that is implicated in the pathogenesis of psoriatic arthritis. We assessed the efficacy and safety of subcutaneous secukinumab, a human anti-interleukin-17A monoclonal antibody, in patients with psoriatic arthritis. METHODS In this phase 3, double-blind, placebo-controlled study undertaken at 76 centres in Asia, Australia, Canada, Europe, and the USA, adults (aged ≥18 years old) with active psoriatic arthritis were randomly allocated in a 1:1:1:1 ratio with computer-generated blocks to receive subcutaneous placebo or secukinumab 300 mg, 150 mg, or 75 mg once a week from baseline and then every 4 weeks from week 4. Patients and investigators were masked to treatment assignment. The primary endpoint was the proportion of patients achieving at least 20% improvement in the American College of Rheumatology response criteria (ACR20) at week 24. Analysis was by intention to treat. This study is registered with ClinicalTrials.gov, number NCT01752634. FINDINGS Between April 14, and Nov 25, 2013, 397 patients were randomly assigned to receive secukinumab 300 mg (n=100), 150 mg (n=100), 75 mg (n=99), or placebo (n=98). A significantly higher proportion of patients achieved an ACR20 at week 24 with secukinumab 300 mg (54 [54%] patients; odds ratio versus placebo 6·81, 95% CI 3·42-13·56; p<0·0001), 150 mg (51 [51%] patients; 6·52, 3·25-13·08; p<0·0001), and 75 mg (29 [29%] patients; 2·32, 1·14-4·73; p=0·0399) versus placebo (15 [15%] patients). Up to week 16, the most common adverse events were upper respiratory tract infections (four [4%], eight [8%], ten [10%], and seven [7%] with secukinumab 300 mg, 150 mg, 75 mg, and placebo, respectively) and nasopharyngitis (six [6%], four [4%], six [6%], and eight [8%], respectively). Serious adverse events were reported by five (5%), one (1%), and four (4%) patients in the secukinumab 300 mg, 150 mg, and 75 mg groups, respectively, compared with two (2%) in the placebo group. No deaths were reported. INTERPRETATION Subcutaneous secukinumab 300 mg and 150 mg improved the signs and symptoms of psoriatic arthritis, suggesting that secukinumab is a potential future treatment option for patients with this disorder. FUNDING Novartis.

Treating spondyloarthritis, including ankylosing spondylitis and psoriatic arthritis, to target: recommendations of an international task force

Background Therapeutic targets have been defined for diseases like diabetes, hypertension or rheumatoid arthritis and adhering to them has improved outcomes. Such targets are just emerging for spondyloarthritis (SpA). Objective To define the treatment target for SpA including ankylosing spondylitis and psoriatic arthritis (PsA) and develop recommendations for achieving the target, including a treat-to-target management strategy. Methods Based on results of a systematic literature review and expert opinion, a task force of expert physicians and patients developed recommendations which were broadly discussed and voted upon in a Delphi-like process. Level of evidence, grade and strength of the recommendations were derived by respective means. The commonalities between axial SpA, peripheral SpA and PsA were discussed in detail. Results Although the literature review did not reveal trials comparing a treat-to-target approach with another or no strategy, it provided indirect evidence regarding an optimised approach to therapy that facilitated the development of recommendations. The group agreed on 5 overarching principles and 11 recommendations; 9 of these recommendations related commonly to the whole spectrum of SpA and PsA, and only 2 were designed separately for axial SpA, peripheral SpA and PsA. The main treatment target, which should be based on a shared decision with the patient, was defined as remission, with the alternative target of low disease activity. Follow-up examinations at regular intervals that depend on the patients status should safeguard the evolution of disease activity towards the targeted goal. Additional recommendations relate to extra-articular and extramusculoskeletal aspects and other important factors, such as comorbidity. While the level of evidence was generally quite low, the mean strength of recommendation was 9–10 (10: maximum agreement) for all recommendations. A research agenda was formulated. Conclusions The task force defined the treatment target as remission or, alternatively, low disease activity, being aware that the evidence base is not strong and needs to be expanded by future research. These recommendations can inform the various stakeholders about expert opinion that aims for reaching optimal outcomes of SpA.

Abatacept in the treatment of patients with psoriatic arthritis: results of a six-month, multicenter, randomized, double-blind, placebo-controlled, phase II trial

OBJECTIVE To assess the safety and efficacy of abatacept, a selective T cell costimulation modulator, in patients with psoriatic arthritis (PsA). METHODS In this 6-month, multicenter, randomized, double-blind, placebo-controlled, phase II study, 170 PsA patients with a psoriasis target lesion (TL) ≥2 cm who had previously taken disease-modifying antirheumatic drugs (DMARDs), including anti-tumor necrosis factor (anti-TNF) agents, were randomized (1:1:1:1) to receive placebo or abatacept at doses of 3 mg/kg, 10 mg/kg, or 30/10 mg/kg (2 initial doses of 30 mg/kg, followed by 10 mg/kg) on days 1, 15, and 29 and then once every 28 days thereafter. The primary end point was the American College of Rheumatology 20% criteria for improvement (ACR20 response) on day 169. Other key end points were magnetic resonance imaging (MRI) scores for joint erosion, osteitis, and synovitis, scores on the Health Assessment Questionnaire (HAQ) and the Short Form-36 (SF-36) health survey, the investigators global assessment of psoriasis, the TL score, and the Psoriasis Area and Severity Index (PASI) score. RESULTS Proportions of patients achieving an ACR20 response were 19%, 33%, 48%, and 42% in the placebo, the abatacept 3 mg/kg, the abatacept 10 mg/kg, and the abatacept 30/10 mg/kg groups, respectively. Compared with placebo, improvements were significantly higher for the abatacept 10 mg/kg (P = 0.006) and 30/10 mg/kg (P = 0.022) groups, but not for 3 mg/kg group (P = 0.121). All abatacept regimens resulted in improved MRI, HAQ, and SF-36 scores, with 10 mg/kg showing the greatest improvements. Improvements in the TL and PASI scores were observed in all abatacept arms; a response according to the investigators global assessment was seen only with 3 mg/kg of abatacept. The safety profiles were similar among the treatment arms. CONCLUSION The results of this study suggest that 10 mg/kg of abatacept, the approved dosage for rheumatoid arthritis and juvenile idiopathic arthritis, may be an effective treatment option for PsA.

Brodalumab, an anti-IL17RA monoclonal antibody, in psoriatic arthritis.

BACKGROUND We assessed the efficacy and safety of brodalumab, a human monoclonal antibody against interleukin-17 receptor A (IL17RA), in a phase 2, randomized, double-blind, placebo-controlled study involving patients with psoriatic arthritis. METHODS We randomly assigned patients with active psoriatic arthritis to receive brodalumab (140 or 280 mg subcutaneously) or placebo on day 1 and at weeks 1, 2, 4, 6, 8, and 10. At week 12, patients who had not discontinued their participation in the study were offered open-label brodalumab (280 mg) every 2 weeks. The primary end point was 20% improvement in American College of Rheumatology response criteria (ACR 20) at week 12. RESULTS Of the 168 patients who underwent randomization (57 in the brodalumab 140-mg group, 56 in the brodalumab 280-mg group, and 55 in the placebo group), 159 completed the double-blind phase and 134 completed 40 weeks of the open-label extension. At week 12, the brodalumab 140-mg and 280-mg groups had higher rates of ACR 20 than the placebo group (37% [P=0.03] and 39% [P=0.02], respectively, vs. 18%); they also had higher rates of 50% improvement (ACR 50) (14% [P=0.05] and 14% [P=0.05] vs. 4%). Rates of 70% improvement were not significantly higher in the brodalumab groups. Similar degrees of improvement were noted among patients who had received previous biologic therapy and those who had not received such therapy. At week 24, ACR 20 response rates in the brodalumab 140-mg and 280-mg groups were 51% and 64%, respectively, as compared with 44% among patients who switched from placebo to open-label brodalumab; responses were sustained through week 52. At week 12, serious adverse events had occurred in 3% of patients in the brodalumab groups and in 2% of those in the placebo group. CONCLUSIONS Brodalumab significantly improved response rates among patients with psoriatic arthritis. Larger studies of longer duration are necessary to assess adverse events. (Funded by Amgen; ClinicalTrials.gov number, NCT01516957 .).

Adalimumab for long-term treatment of psoriatic arthritis: 2-year data from the Adalimumab Effectiveness in Psoriatic Arthritis Trial (ADEPT)

Objective: To evaluate the long-term effectiveness and tolerability of adalimumab in the treatment of psoriatic arthritis (PsA). Methods: Patients with PsA who completed a 24-week, double-blind study of adalimumab versus placebo were eligible to enroll in an open-label extension study and receive adalimumab 40 mg subcutaneously every other week for up to an additional 120 weeks. At the time of this analysis, available efficacy evaluations throughout 2 years of treatment (n  =  245) included American College of Rheumatology (ACR) 20%, 50% and 70% improvement scores, measures of joint disease and skin disease, disability and quality of life; modified total Sharp scores (mTSS) were available for 2.75 years of treatment for patients who received adalimumab in the 24-week study. Results: After 24 weeks of double-blind treatment, the mean change in mTSS was −0.2 for the adalimumab group (N  =  144) and 1.0 for the placebo group (N  =  152; p<0.001), and outcomes for all individual ACR component variables were significantly improved in adalimumab compared with placebo-treated patients. Compared with 24-week responses, inhibition of radiographic progression and improvements in joint disease were maintained in most patients during long-term, open-label adalimumab treatment. Also, improvements in skin disease were maintained, with >20% of patients achieving the strict criterion of psoriasis area and severity index 100. The nature and frequency of adverse events during long-term adalimumab treatment were consistent with the safety profile during short-term treatment. Conclusions: The clinical and radiographic efficacy of adalimumab demonstrated during short-term treatment was sustained during long-term treatment. Adalimumab has a favourable risk–benefit profile in patients with PsA. Trial registration number: NCT00195689.