Correction to: Safety and effectiveness of peficitinib (ASP015K) in patients with rheumatoid arthritis: interim data (22.7 months mean peficitinib treatment) from a long-term, open-label extension study in Japan, Korea, and Taiwan.

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Safety and effectiveness of peficitinib (ASP015K) in patients with rheumatoid arthritis: interim data (22.7 months mean peficitinib treatment) from a long-term, open-label extension study in Japan, Korea, and Taiwan.

BACKGROUND: Peficitinib (ASP015K), a novel oral Janus kinase inhibitor, has demonstrated efficacy and safety for the treatment of rheumatoid arthritis (RA) in randomized, controlled trials of up to 52 weeks' duration. However, safety and effectiveness after long-term treatment have not been assessed. METHODS: This was an interim analysis of an ongoing open-label, multicenter extension study in RA patients who completed phase 2b (RAJ1; 12 weeks) and phase 3 (RAJ3 and RAJ4; 52 weeks) peficitinib studies in Asia (mainly Japan). Eligible patients (n = 843) received oral peficitinib once daily (100 mg, or 50 mg for patients transferring from RAJ1). The peficitinib dose could be increased (up to 150 mg) or reduced (to 50 mg) at the discretion of the investigator. Efficacy variables assessed included American College of Rheumatology (ACR) response rates, ACR components, and disease activity score in 28 joints based on C-reactive protein (DAS28-CRP). RESULTS: Results up to May 2018 are summarized. Mean peficitinib duration of exposure was 22.7 months and the maximum dose was 100 mg in most (66.5%) patients. ACR responses were maintained during the extension study, with ACR20/50/70 response rates of 71.6%, 52.1%, and 34.7% at week 0 and 78.9%, 61.4%, and 42.7% at end of treatment, respectively. ACR components and DAS28-CRP showed improvements from baselines of the preceding studies and continued to show improvements during the extension study. Treatment-emergent adverse events (TEAEs) were reported in 757/843 (89.8%) patients, the most common being nasopharyngitis (39.7%) and herpes zoster (11.7%). The majority of TEAEs were severity grade 1/2. Drug-related TEAEs leading to permanent study drug discontinuation occurred in 55/843 (6.5%) patients. Regarding AEs of special interest, the incidence per 100 patient-years of serious infections was 2.3 (95% CI 1.6 - 3.1), herpes zoster-related disease 6.8 (95% CI, 5.6 - 8.3), and malignancies 1.1 (95% CI, 0.7 - 1.8). One death from diffuse large B cell lymphoma during the study and one death from uterine sarcoma after the study were considered probably and possibly related to study drug, respectively. CONCLUSIONS: The effectiveness of peficitinib was maintained or improved during long-term administration and treatment up to 6 years was well tolerated in Asian patients with RA. TRIAL REGISTRATION: ClinicalTrials.gov, NCT01638013, registered retrospectively 11 July 2012.

Efficacy and safety of peficitinib (ASP015K) in patients with rheumatoid arthritis and an inadequate response to methotrexate: results of a phase III randomised, double-blind, placebo-controlled trial (RAJ4) in Japan.

OBJECTIVE: To evaluate the efficacy and safety of the oral Janus kinase (JAK) inhibitor peficitinib versus placebo in Japanese patients with rheumatoid arthritis (RA). METHODS: In this multicentre, double-blind, parallel-group, placebo-controlled phase III study, patients with RA and inadequate response to methotrexate (MTX) were randomised 1:1:1 to placebo, peficitinib 100 mg once daily or peficitinib 150 mg once daily with MTX for 52 weeks. Based on baseline randomisation, at week 12, non-responders receiving placebo were switched to peficitinib until the end of treatment; the remaining patients were switched to peficitinib at week 28. Primary efficacy variables were American College of Rheumatology (ACR)20 response rate at week 12/early termination (ET) and change from baseline in van der Heijde-modified total Sharp score (mTSS) at week 28/ET. RESULTS: 519 patients were randomised and treated. Significantly more (p<0.001) peficitinib (58.6%, 100 mg; 64.4%, 150 mg) than placebo (21.8%) recipients achieved ACR20 response at week 12/ET. Significantly lower (p<0.001) mean changes from baseline in mTSS at week 28/ET occurred in peficitinib (1.62, 100 mg; 1.03, 150 mg) than placebo (3.37) recipients. Peficitinib was associated with haematological and biochemical parameter changes, and increased incidence of serious infections and herpes zoster-related disease. One death from suicide occurred in a patient in the placebo group after switching to peficitinib 100 mg. CONCLUSIONS: In Japanese patients with RA and inadequate response to MTX, peficitinib demonstrated significant superiority versus placebo in reducing RA symptoms and suppressing joint destruction. Peficitinib had an acceptable safety and tolerability profile, with no new safety signals compared with other JAK inhibitors. TRIAL REGISTRATION NUMBER: NCT02305849.

Efficacy and safety of peficitinib (ASP015K) in patients with rheumatoid arthritis and an inadequate response to conventional DMARDs: a randomised, double-blind, placebo-controlled phase III trial (RAJ3).

OBJECTIVES: To investigate the efficacy and safety of peficitinib, an oral Janus kinase inhibitor, in patients with rheumatoid arthritis (RA). METHODS: In this double-blind phase III study, patients with RA and an inadequate response to prior disease-modifying anti-rheumatic drugs (DMARDs) were randomised to peficitinib 100 mg once daily, peficitinib 150 mg once daily, placebo or open-label etanercept for 52 weeks' treatment; placebo-treated patients were switched at week 12 to peficitinib 100 or 150 mg once daily. The primary endpoint was American College of Rheumatology (ACR)20 response at week 12/early termination (ET). Secondary endpoints (assessed throughout) included ACR20, ACR50 and ACR70 response, changes from baseline in disease activity scores (DAS)28 and ACR core parameters, adverse events (AEs) and changes in clinical or laboratory measurements. RESULTS: In total, 507 patients received treatment. ACR20 response rates at week 12/ET were significantly higher in the peficitinib 100 mg (57.7%) and 150 mg (74.5%) groups versus placebo (30.7%) (p<0.001). ACR50/70 response rates were also higher for both peficitinib doses versus placebo. Improvements in ACR response were maintained until week 52. Changes from baseline in DAS28-C-reactive protein/erythrocyte sedimentation rate and the ACR core set were significantly greater for both peficitinib doses versus placebo at week 12/ET (p<0.001). AE incidence was similar across treatment arms. Incidence of serious infection and herpes zoster-related disease was higher with peficitinib versus placebo, but with no clear dose-dependent increase. CONCLUSIONS: In patients with RA and inadequate response to DMARDs, peficitinib 100 mg once daily or 150 mg once daily was efficacious in reducing RA symptoms and was well tolerated compared with placebo. TRIAL REGISTRATION NUMBER: NCT02308163.

Phenytoin stimulates chondrogenic differentiation in mouse clonal chondrogenic EC cells, ATDC5.

Phenytoin (DPH) is known to affect bone formation. However, the mechanism of this effect has not been well understood. In this study, we evaluated the effects of DPH on cartilage formation in a model system using ATDC5 cells, a clonal murine chondrogenic cell line. Alcian blue staining for cartilage nodules and real-time reverse-transcription polymerase chain reaction for the expression of genes encoding type II collagen, aggrecan, transforming growth factor (TGF)-beta1, bone morphogenetic protein (BMP)-4, parathyroid hormone-related peptide (PTHrP), indian hedgehog (Ihh), and patched (Ptc) were performed in ATDC5 cells cultured with DPH. The ATDC5 cells demonstrated enhanced cartilage formation in cultures with DPH. During promoted chondrogenic differentiation, it was observed that DPH increased the mRNA expression of TGF-beta1, BMP-4, Ihh, and Ptc, in a dose-dependent manner on Days 5 to 15. In contrast, other antiepileptic drugs, phenobarbital and valproic acid had no effects on chondrogenesis in ATDC5 cells and osteogenesis in MC3T3-E1 cells. Our results provide fundamental evidence that DPH has a direct stimulatory effect on cartilage formation by regulating TGF-beta and hedgehog signaling molecules, and that DPH effect on bone formation, including chondrogenesis and osteogenesis, is distinct from other antiepileptic drugs as suggested in clinical settings.