Post hoc analysis of clinical characteristics of patients with radiographic progression in a Japanese phase 3 trial of peficitinib and methotrexate treatment (RAJ4).

OBJECTIVE: To determine the efficacy of peficitinib in reducing joint damage and predictive factors affecting treatment response in Japanese patients with rheumatoid arthritis. METHODS: This post hoc analysis used data from a placebo-controlled, phase 3 trial (RAJ4) of peficitinib in patients with rheumatoid arthritis and inadequate response to methotrexate. Erosion and joint space narrowing (JSN) were assessed at baseline and at Week 28/early termination of treatment using the van der Heijde-modified Sharp method. A univariate logistic regression analysis of change from baseline in a modified total Sharp score identified predictive factors with significant treatment interaction; the effects of these factors on treatment response were further evaluated using a multivariate model. RESULTS: The analyses included 481 patients. For most joint groups, peficitinib demonstrated a reduced change from baseline at Week 28/early termination in erosion and JSN scores versus placebo; a numerically greater effect was observed with peficitinib 150 mg versus 100 mg. Baseline C-reactive protein (CRP) and prednisolone dose were identified as clinically significant negative predictive factors: the treatment effect decreased as CRP or prednisolone dose increased for both peficitinib doses. CONCLUSIONS: Peficitinib 100 mg and 150 mg reduced joint damage versus placebo, across almost all joint groups. Higher baseline CRP and/or prednisolone dose were associated with reduced peficitinib efficacy. CLINICALTRIALS.GOV IDENTIFIER: NCT02305849.

A pooled analysis of serious infections and herpes zoster-related disease in Asian patients with rheumatoid arthritis treated with peficitinib (ASP015K) over a median of 3 years.

OBJECTIVE: To analyse serious infection (SI) and herpes zoster-related disease (HZD) during long-term treatment of rheumatoid arthritis with the oral Janus kinase inhibitor, peficitinib (ASP015K). METHODS: This was a post hoc analysis of pooled data from one Phase 2b study and two Phase 3 studies and final data from a long-term extension study of peficitinib in Asian rheumatoid arthritis patients. Two pooled datasets were analysed (Phase 3 studies and Phase 2/3 studies). Univariate and multivariate Cox regression analyses explored relationships between exposure-adjusted incidence rate of SI and HZD, peficitinib dose, and baseline factors. RESULTS: Total peficitinib exposure for 1052 patients receiving once-daily peficitinib in the pooled Phase 2/3 Asian studies was 2998.9 patient-years. Exposure-adjusted incidence rates (95% confidence interval) of SI and HZD were 2.7 (2.2, 3.4) and 6.9 (6.0, 8.0) per 100 patient-years, respectively, in pooled Phase 2/3 studies. Advanced age was prognostic for SI and HZD, while baseline prednisolone dose was prognostic for SI. There was no temporal relationship between either adverse event and prolonged peficitinib administration. CONCLUSIONS: As expected in this peficitinib-treated population, older patients had increased risk of SI and HZD, and those receiving higher prednisolone doses had increased risk of SI.

Patient- and physician-reported outcomes from two phase 3 randomized studies (RAJ3 and RAJ4) of peficitinib (ASP015K) in Asian patients with rheumatoid arthritis.

BACKGROUND: Peficitinib (ASP015K), a novel oral Janus kinase inhibitor, has demonstrated efficacy and safety in the treatment of patients with rheumatoid arthritis (RA). This study evaluated the effect of peficitinib on patient- and physician-reported outcomes in Asian patients with RA and an inadequate response to prior disease-modifying antirheumatic drugs (DMARDs). METHODS: Patients from two randomized, placebo-controlled, double-blind, phase 3 trials (RAJ3 and RAJ4) received once-daily peficitinib 100 mg, peficitinib 150 mg, or placebo, alone or in combination with DMARDs (RAJ3), or in combination with methotrexate (RAJ4). Mean changes in Work Productivity and Activity Impairment (WPAI) questionnaire domain scores from baseline, and percentages of patients achieving minimal clinically important differences (MCIDs) for patient- and physician-reported outcomes (WPAI, Health Assessment Questionnaire - Disability Index [HAQ-DI], and Subject's Global Assessment of Pain [SGAP]), and Physician's Global Assessment of disease activity (PGA) were evaluated at weeks 4, 8, 12, and 12/early termination (ET). RESULTS: Data from 1025 patients were analyzed. At week 12/ET in both studies, patients who received peficitinib 100 mg or 150 mg reported significantly improved WPAI domain scores from baseline (except for absenteeism in RAJ4) compared with placebo (both doses, p<0.05). A higher proportion of peficitinib- versus placebo-treated patients achieved MCID in WPAI, HAQ-DI, SGAP, and PGA in studies RAJ3 and RAJ4. Significant differences with peficitinib versus placebo were evident in both studies as early as week 4 in HAQ-DI (peficitinib 150 mg only), SGAP, and PGA, and week 8 in WPAI loss of work productivity and daily activity impairment. At week 12/ET, significantly higher proportions of patients receiving peficitinib versus placebo achieved MCID in HAQ-DI, SGAP, PGA, and WPAI domains of presenteeism (RAJ3 only), loss of work productivity (RAJ3 only), and daily activity impairment (p<0.05 for all comparisons). CONCLUSIONS: Peficitinib 100 mg or 150 mg administered daily over 12 weeks resulted in clinically meaningful improvements in outcomes that are important to RA patients, including pain, physical function, and work productivity and activity. These observations were reinforced through similar improvements in physicians' rating of disease activity. TRIAL REGISTRATION: RAJ3: ClinicalTrials.gov, NCT02308163 , registered 4 December 2014. RAJ4: ClinicalTrials.gov, NCT02305849 , registered 3 December 2014.

Exposure-response modeling of peficitinib efficacy in patients with rheumatoid arthritis.

The aim was to analyze the relationship between peficitinib exposure and efficacy response according to American College of Rheumatology (ACR) 20 criteria and 28-joint disease activity score based on C-reactive protein (DAS28-CRP) in rheumatoid arthritis (RA) patients, and to identify relevant covariates by developing exposure-response models. The analysis incorporated results from three multicenter, placebo-controlled, double-blind studies. As an exposure parameter, individual post hoc pharmacokinetic (PK) parameters were obtained from a previously constructed population PK model. Longitudinal ACR20 response rate and individual longitudinal DAS28-CRP measurements were modeled by a non-linear mixed effect model. Influential covariates were explored, and their effects on efficacy were quantitatively assessed and compared. The exposure-response models of effect of peficitinib on duration-dependent increase in ACR20 response rate and decrease in DAS28-CRP were adequately described by a continuous time Markov model and an indirect response model, respectively, with a sigmoidal Emax saturable of drug exposure in RA patients. The significant covariates were DAS28-CRP and total bilirubin at baseline for the ACR20 response model, and CRP at baseline and concomitant methotrexate treatment for the DAS28-CRP model. The covariate effects were highly consistent between the two models. Our exposure-response models of peficitinib in RA patients satisfactorily described duration-dependent improvements in ACR20 response rates and DAS28-CRP measurements, and provided consistent covariate effects. Only the ACR20 model incorporated a patient's subjective high expectations just after the start of the treatment. Therefore, due to their similarities and differences, both models may have relevant applications in the development of RA treatment. CLINICAL TRIAL REGISTRATION: NCT01649999 (RAJ1), NCT02308163 (RAJ3), NCT02305849 (RAJ4).

Safety and Effectiveness of Peficitinib (ASP015K) in Patients with Rheumatoid Arthritis: Final Results (32 Months of Mean Peficitinib Treatment) From a Long-Term, Open-Label Extension Study in Japan, Korea, and Taiwan.

INTRODUCTION: This final analysis of a long-term extension (LTE) study assessed the safety, tolerability, and effectiveness of peficitinib (ASP015K), a pan-Janus kinase inhibitor, in Asian patients with rheumatoid arthritis (RA). METHODS: Patients had previously completed the 12-week phase 2b (RAJ1), or 52-week phase 3 (RAJ3 and RAJ4) peficitinib studies in Japan, Korea, and Taiwan, and received oral peficitinib 50 or 100 mg/day. Dose increase to 150 mg/day or reduction to 50 mg/day was permitted. Efficacy endpoints included American College of Rheumatology (ACR)20/50/70 response rates, 28-joint Disease Activity Score with C-reactive protein (DAS28-CRP), and ACR components. Safety endpoints included treatment-emergent adverse events (TEAEs), and incidence rates (IRs) of adverse events of special interest per 100 patient-years (PY). RESULTS: Overall, 843 patients received peficitinib for a mean 32.0 months (maximum 85.2 months), and most (64.4%) received peficitinib 100 mg/day as a maximum dose. Respective ACR20/50/70 response rates were maintained from baseline (week 0 of LTE; 71.6, 52.1, and 34.7%) to end of treatment (78.7, 63.3, and 44.1%); continuous improvements in ACR components and DAS28-CRP were observed from the baselines of preceding studies and throughout the LTE. Overall, 796/843 (94.4%) patients experienced TEAEs; most were severity grade 1/2. Most common TEAEs were nasopharyngitis (47.0%) and herpes zoster (17.3%). Drug-related TEAEs leading to permanent discontinuation occurred in 140 (16.6%) patients, and IRs (95% confidence interval) per 100 PY of serious infections, herpes zoster-related disease, and malignancies were 2.7 (2.1, 3.4), 7.3 (6.2, 8.6), and 1.2 (0.9, 1.8), respectively. Two deaths occurred during the study; one each from diffuse large B cell lymphoma and pneumonia, which were, respectively considered probably and possibly related to study drug. CONCLUSIONS: Improvements in effectiveness variables were maintained during this long-term study of peficitinib in Asian patients with RA; peficitinib was generally well tolerated over a mean 32 months' duration. TRIAL REGISTRATION: ClinicalTrials.gov. NCT01638013, retrospectively registered on 11 July 2012 https://clinicaltrials.gov/ct2/show/NCT01638013 .

Population pharmacokinetic analysis of peficitinib in patients with rheumatoid arthritis.

AIMS: To analyse the population pharmacokinetics (PK) of peficitinib in patients with rheumatoid arthritis (RA) and assess the potential PK covariates to identify the requirement for dose adjustment in RA patients. METHODS: The analysis incorporated 2464 observations from 98 healthy volunteers and 4919 observations from 989 RA patients. A population PK model for peficitinib in RA patients was constructed by a nonlinear mixed effect model using NONMEM with prior information from a healthy volunteer model. RESULTS: A 2-compartment model with sequential zero- and first-order absorption and lag time was constructed for RA patients. Covariate exploration in the RA patient model revealed that estimated glomerular filtration rate (eGFR) and lymphocyte count had a significant effect on apparent total systemic clearance (CL), which was 91.7 L/h (2.3% relative standard error). Compared with the mean population CL, the model predicted mean changes in CL of 12.3 and -10.7% in patients with observed minimum and maximum lymphocyte count of 500 and 4600 106 /L, respectively, and mean changes in CL of -17.8 and 16.7% in patients with minimum and maximum eGFR of 36.4 and 188 mL/min/1.73m2 , respectively. The simulated population mean area under plasma concentration-time curve for 24 hours after dosing showed a 1.35-fold increase in patients with severe renal impairment (eGFR 22.5 mL/min/1.73m2 ) compared with patients with reference eGFR (91.5 mL/min/1.73m2 ). CONCLUSION: The population PK model identified eGFR and lymphocyte count as covariates for CL. The magnitude of changes was not considered clinically relevant, indicating no requirement for dose adjustment.

A pooled safety analysis of peficitinib (ASP015K) in Asian patients with rheumatoid arthritis treated over a median of 2 years.

OBJECTIVE: To evaluate the safety of peficitinib for the treatment of rheumatoid arthritis (RA) in Asian patients. METHODS: Safety data from one Phase 2b, two Phase 3, and one open-label long-term extension study [data cut-off 31 May 2018] were pooled into Phase 3 studies (peficitinib 100 and 150 mg/day, and placebo) and Phase 2/3 studies (all peficitinib-treated patients). Incidence rates per 100 patient-years (PY) of adverse events (AEs) of special interest were calculated. RESULTS: Overall, 1052 patients received peficitinib for 2336.3 PY of exposure (median 2.1 years); four deaths occurred, including one death after the studies. AE incidence was similar across peficitinib 100 and 150 mg/day groups (Phase 3 studies). Respective peficitinib and placebo incidence rates (95% confidence interval) per 100 PY were 2.9 (1.9, 4.6) and 0.0 for serious infections, 5.7 (4.2, 7.9) and 2.3 (0.6, 9.4) for herpes zoster-related disease, and 0.6 (0.2, 1.6) and 1.2 (0.2, 8.3) for malignancies (excluding non-melanoma skin cancer) (Phase 3 studies), and 0.1 (0.0, 0.3) for venous thromboembolism in all peficitinib-treated patients (Phase 2/3 studies). CONCLUSION: Peficitinib was well tolerated in Asian patients with RA over a median of 2 years, with no observed dose or temporal dependency for AEs with prolonged administration.

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.

An amendment to this paper has been published and can be accessed via the original article.

Peficitinib for the treatment of rheumatoid arthritis: an overview from clinical trials.

INTRODUCTION: The treatment of rheumatoid arthritis (RA), a chronic, systemic, autoimmune disease, has been greatly advanced by the introduction of biologic disease-modifying antirheumatic drugs (DMARDs); however, many patients still fail to achieve disease remission. Peficitinib, an orally bioavailable inhibitor of the Janus kinase (JAK) receptor family, was approved in Japan in 2019 and Korea in 2020 for the treatment of RA. AREAS COVERED: This review provides an overview of JAK inhibitors currently marketed or in development; the pharmacodynamics and pharmacokinetics of peficitinib; and the efficacy and safety data for peficitinib from Phase 2b and 3 trials. EXPERT OPINION: Peficitinib has proven clinical efficacy in Asian patients (Japan, Korea, and Taiwan) with RA who have an inadequate response to conventional DMARDs. In Phase 3 trials, clinical improvements and prevention of joint destruction were demonstrated for both 100 mg and 150 mg once-daily peficitinib versus placebo, and treatment for up to 52 weeks was well tolerated. Safety signals, in particular the increased incidence of herpes zoster-related disease, appeared in line with other JAK inhibitors. Post-launch monitoring will establish the long-term safety and effectiveness of this drug, and further studies are necessary to determine its potential use in non-Asian populations.

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.

Self-sustained circadian rhythm in cultured human mononuclear cells isolated from peripheral blood.

Disturbed circadian rhythmicity is associated with human diseases such as sleep and mood disorders. However, study of human endogenous circadian rhythm is laborious and time-consuming, which hampers the elucidation of diseases. It has been reported that peripheral tissues exhibit circadian rhythmicity as the suprachiasmatic nucleus-the center of the biological clock. We tried to study human circadian rhythm using cultured peripheral blood mononuclear cells (PBMCs) obtained from a single collection of venous blood. Activated human PBMCs showed self-sustained circadian rhythm of clock gene expression, which indicates that they are useful for investigating human endogenous circadian rhythm.

A Novel Layered Silicate with a Helical Morphology.

Helices composed of stacked layers are present in the novel silicate obtained from a silica sol and NaOH by hydrothermal synthesis in the presence of tetramethylammonium (TMA) hydroxide and 1,4-dioxane. The helical morphology is evident in scanning electron micrographs (see picture). The TMA and sodium ions of the silicate are readily replaced by protons, and on heating to 200°C a reversible phase transition occurs in which water molecules are lost from between the layers.