Six-month safety and effectiveness of tofacitinib in patients with rheumatoid arthritis in Japan: Interim analysis of post-marketing surveillance

OBJECTIVES

We evaluated the real-world safety/effectiveness of tofacitinib, an oral Janus kinase inhibitor for the treatment of rheumatoid arthritis (RA), in patients with RA in Japan registered in a post-marketing surveillance study.

METHODS

This interim analysis included data from July 2013 to December 2018. Adverse events (AEs), serious AEs (SAEs), Simplified Disease Activity Index (SDAI)/Clinical Disease Activity Index (CDAI)/Disease Activity Score in 28 joints, erythrocyte sedimentation rate [DAS28-4(ESR)] scores, and rates of SDAI/CDAI/DAS28-4(ESR)-defined remission and low disease activity were analysed using 6 months of data. Risk factors for serious infections were assessed by multivariable analyses.

RESULTS

Safety and disease activity were evaluated in 6866 and 6649 patients, respectively. Overall, 32.73%/7.37% of patients reported AEs/SAEs. Clinically important AEs with tofacitinib included serious infections/infestations [3.13% of patients; incidence rate (IR; patients with events) 6.91/100 patient-years (PY)], herpes zoster (3.63%; IR 8.02/100 PY), and malignancies (0.68%; IR 1.45/100 PY). SDAI/CDAI/DAS28-4(ESR) scores and remission/low disease activity rates improved over 6 months. Male sex, older age, Steinbrocker's stage IV, history of infection, and diabetes mellitus at baseline were independent risk factors for serious infection.

CONCLUSIONS

In patients with RA receiving tofacitinib in Japan, safety was consistent with the reported profile, and disease activity improved over 6 months.

STUDY IDENTIFIER

NCT01932372.

Validation of claims-based algorithms for rheumatoid arthritis in Japan: Results from the VALIDATE-J study

AIM

Validity of Algorithms in Large Databases: Infectious Diseases, Rheumatoid Arthritis, and Tumor Evaluation in Japan (VALIDATE-J) study examined algorithms for identifying rheumatoid arthritis (RA) in Japanese claims data.

METHODS

VALIDATE-J was a multicenter, cross-sectional retrospective study. Disease-identifying algorithms were used to detect RA diagnosed between January 2012 and December 2016 using claims data from two Japanese hospitals. An RA diagnosis was confirmed using one of four gold standard definitions. Positive predictive values (PPVs) were calculated for prevalent (regardless of baseline RA-free period) and incident (preceded by a 12-month RA-free period) cases.

RESULTS

Of patients identified using claims-based algorithms, a random sample of 389 prevalent and 134 incident cases of RA were included. Cases identified by an RA diagnosis, no diagnosis of psoriasis, and treatment with any disease-modifying antirheumatic drugs (DMARDs) resulted in the highest PPVs versus other claims-based treatment categories (29.0%-88.3% [prevalent] and 41.0%-78.2% [incident]); cases identified by an RA diagnosis, no diagnosis of psoriasis, and glucocorticoid-only treatment had the lowest PPVs. Across claims-based algorithms, PPVs were highest when a physician diagnosis or decision by adjudicators (confirmed and probable cases) was used as the gold standard and were lowest when American College of Rheumatology/European Alliance of Associations for Rheumatology 2010 criteria were applied. PPVs of claims-based algorithms for RA in patients aged ≥66 years were slightly higher versus a USA Medicare population (maximum PPVs of 95.0% and 88.9%, respectively).

CONCLUSION

VALIDATE-J demonstrated high PPVs for most claims-based algorithms for diagnosis of prevalent and incident RA using Japanese claims data. These findings will help inform appropriate RA definitions for future claims database research in Japan.

Validity of claims-based diagnoses for infectious diseases common among immunocompromised patients in Japan

BACKGROUND

To validate Japanese claims-based disease-identifying algorithms for herpes zoster (HZ), Mycobacterium tuberculosis (MTB), nontuberculous mycobacteria infections (NTM), and Pneumocystis jirovecii pneumonia (PJP).

METHODS

VALIDATE-J, a multicenter, cross-sectional, retrospective study, reviewed the administrative claims data and medical records from two Japanese hospitals. Claims-based algorithms were developed by experts to identify HZ, MTB, NTM, and PJP cases among patients treated 2012-2016. Diagnosis was confirmed with three gold standard definitions; positive predictive values (PPVs) were calculated for prevalent (regardless of baseline disease-free period) and incident (preceded by a 12-month disease-free period for the target conditions) cases.

RESULTS

Of patients identified using claims-based algorithms, a random sample of 377 cases was included: HZ (n = 95 [55 incident cases]); MTB (n = 100 [58]); NTM (n = 82 [50]); and PJP (n = 100 [84]). PPVs ranged from 67.4-70.5% (HZ), 67.0-90.0% (MTB), 18.3-63.4% (NTM), and 20.0-45.0% (PJP) for prevalent cases, and 69.1-70.9% (HZ), 58.6-87.9% (MTB), 10.0-56.0% (NTM), and 22.6-51.2% (PJP) for incident cases, across definitions. Adding treatment to the algorithms increased PPVs for HZ, with a small increase observed for prevalent cases of NTM.

CONCLUSIONS

VALIDATE-J demonstrated moderate to high PPVs for disease-identifying algorithms for HZ and MTB using Japanese claims data.

Malignancy risk with tofacitinib versus TNF inhibitors in rheumatoid arthritis: results from the open-label, randomised controlled ORAL Surveillance trial

OBJECTIVES

To evaluate malignancies and their associations with baseline risk factors and cardiovascular risk scores with tofacitinib versus tumour necrosis factor inhibitors (TNFi) in patients with rheumatoid arthritis (RA).

METHODS

In an open-label, randomised controlled trial (ORAL Surveillance; NCT02092467), 4362 patients with RA aged ≥50 years with ≥1 additional cardiovascular risk factor received tofacitinib 5 (N=1455) or 10 mg two times per day (N=1456) or TNFi (N=1451). Incidence rates (IRs; patients with first events/100 patient-years) and HRs were calculated for adjudicated malignancies excluding non-melanoma skin cancer (NMSC), NMSC and subtypes. Post hoc analyses for malignancies excluding NMSC, lung cancer and NMSC included risk factors identified via simple/multivariable Cox models and IRs/HRs categorised by baseline risk factors, history of atherosclerotic cardiovascular disease (HxASCVD) and cardiovascular risk scores.

RESULTS

IRs for malignancies excluding NMSC and NMSC were higher with tofacitinib (combined and individual doses) versus TNFi. Risk of lung cancer (most common subtype with tofacitinib) was higher with tofacitinib 10 mg two times per day versus TNFi. In the overall study population, the risk of malignancies excluding NMSC was similar between both tofacitinib doses and TNFi until month 18 and diverged from month 18 onwards (HR (95% CIs) for combined tofacitinib doses: 0.93 (0.53 to 1.62) from baseline to month 18 vs 1.93 (1.22 to 3.06) from month 18 onwards, interaction p=0.0469). Cox analyses identified baseline risk factors across treatment groups for malignancies excluding NMSC, lung cancer and NMSC; interaction analyses generally did not show statistical evidence of interaction between treatment groups and risk factors. HxASCVD or increasing cardiovascular risk scores were associated with higher malignancy IRs across treatments.

CONCLUSIONS

Risk of malignancies was increased with tofacitinib versus TNFi, and incidence was highest in patients with HxASCVD or increasing cardiovascular risk. This may be due to shared risk factors for cardiovascular risk and cancer.

TRIAL REGISTRATION NUMBERS

NCT02092467, NCT01262118, NCT01484561, NCT00147498, NCT00413660, NCT00550446, NCT00603512, NCT00687193, NCT01164579, NCT00976599, NCT01059864, NCT01359150, NCT02147587, NCT00960440, NCT00847613, NCT00814307, NCT00856544, NCT00853385, NCT01039688, NCT02281552, NCT02187055, NCT02831855, NCT00413699, NCT00661661.

Validation of a claims-based algorithm to identify cases of ulcerative colitis in Japan

BACKGROUND AND AIM

The prevalence of ulcerative colitis (UC) is increasing in Japan. Validated claims-based definitions are required to investigate the epidemiology of UC and its treatment and disease course in clinical practice. This study aimed to develop a claims-based algorithm for UC in Japan.

METHODS

A committee of epidemiologists, gastroenterologists, and internal medicine physicians developed a claims-based definition for UC, based on diagnostic codes and claims for UC treatments, procedures (cytapheresis), or surgery (postoperative claims). Claims data and medical records for a random sample of 200 cases per site at two large tertiary care academic centers in Japan were used to calculate the positive predictive value (PPV) of the algorithm for three gold standards of diagnosis, defined as physician diagnosis in the medical records, adjudicated cases, or registration in the Japanese Intractable Disease Registry (IDR).

RESULTS

Overall, 1139 claims-defined UC cases were identified. Among 393 randomly sampled cases (mean age 44; 48% female), 94% had received ≥ 1 systemic treatment (immunosuppressants, tumor necrosis factor inhibitors, corticosteroids, or antidiarrheals), 7% had cytapheresis, and 7% had postoperative claims. When physician diagnosis was used as a gold standard, PPV was 90.6% (95% confidence interval [CI]: 87.7-93.5). PPV with expert adjudication was also 90.6% (95% CI: 87.7-93.5). PPVs with enrollment in the IDR as gold standard were lower at 41.5% (95% CI: 36.6-46.3) due to incomplete case registration.

CONCLUSIONS

The claims-based algorithm developed for use in Japan is likely to identify UC cases with high PPV for clinical studies using administrative claims databases.

POS0651 CLINICAL AND FUNCTIONAL RESPONSE TO TOFACITINIB IN PATIENTS WITH RHEUMATOID ARTHRITIS: PROBABILITY PLOT ANALYSIS OF RESULTS FROM A 48-WEEK PHASE 3b/4 METHOTREXATE WITHDRAWAL STUDY

Background:

The Phase 3b/4 study ORAL Shift (NCT02831855) demonstrated sustained efficacy/safety of tofacitinib modified-release 11 mg QD following MTX withdrawal, that was non-inferior to continued tofacitinib + MTX use, in patients (pts) with moderate to severe RA who achieved LDA with tofacitinib + MTX at Week (W)24.1

Objectives:

To assess differences and similarities in clinical/functional responses in pts receiving tofacitinib ± MTX in ORAL Shift.

Methods:

In ORAL Shift, pts received open-label tofacitinib + MTX to W24; at W24, pts who achieved CDAI LDA were randomised to receive tofacitinib + MTX or tofacitinib + placebo (PBO) from W24–48. In this post hoc analysis, clinical efficacy endpoints were ACR-N (minimum % change from baseline [BL; Δ] at W48 achieved by each pt in 3 efficacy measures), ΔDAS28-4(ESR), and DAS28-4(ESR) remission/LDA (scores ≤3.2) and moderate/high disease activity (scores >3.2). Functional efficacy endpoints were ΔHAQ-DI and HAQ-DI clinically relevant functional progression (CRFP) status at W48, defined as failure to achieve improvement in HAQ-DI ≥ minimum clinically important difference (MCID; ≥0.22 decrease from BL in HAQ-DI). Thus, CRFP was defined as <0.22 decrease, no change or increase from BL in HAQ-DI at W48. All efficacy endpoints were summarised descriptively. Cumulative probability plots of ACR-N and ΔHAQ-DI were produced. Median of mean CRP values from BL–W24 and >W24–48 were assessed by response subgroups.

Results:

266 pts receiving tofacitinib + MTX and 264 pts receiving tofacitinib + PBO in W24–48 were included. At W48: mean ACR-N was numerically greater with tofacitinib + MTX vs tofacitinib + PBO (60.8 vs 53.1); mean decrease in HAQ-DI was generally similar between groups (-0.71 vs -0.67); mean decrease in DAS28-4(ESR) was numerically greater with tofacitinib + MTX vs tofacitinib + PBO (-2.95 vs -2.68). The differences/similarities between groups in ACR-N and ΔHAQ-DI were also seen in cumulative probability plots (Figure 1). CRFP rates were numerically lower with tofacitinib + MTX (18.7%) vs tofacitinib + PBO (23.5%), and in pts with remission/LDA (tofacitinib + MTX, 12.1%; tofacitinib + PBO, 16.8%) vs moderate/high disease activity (tofacitinib + MTX, 26.2%; tofacitinib + PBO, 30.8%). Median of mean CRP over time was generally numerically lower in pts with CRFP vs non-CRFP and DAS28-4(ESR)-defined remission/LDA vs moderate/high disease activity; and in those receiving tofacitinib + PBO vs tofacitinib + MTX, irrespective of CRFP or DAS28-4(ESR) disease status (Table 1).

Table 1.

Median of mean CRPa up to W48 by response subgroups

Tofacitinib 11 mg QD + MTXTofacitinib 11 mg QD + PBOMean CRP,amedian (IQR) [n]>BL–W24>W24–48>BL–W24>W24–48HAQ-DI CRFP2.84 (1.15–7.30)2.30 (0.82–4.75)1.45 (0.77–4.42)2.28 (0.53–7.28)[45][46][56][56]HAQ-DI non-CRFP2.81 (1.09–6.19)2.91 (1.19–5.84)2.26 (0.98–4.63)2.47 (1.13–5.53)[195][195][176][178]DAS28-4(ESR) remission/LDA2.48 (1.05–4.95)2.46 (1.07–4.76)1.70 (0.89–4.14)1.95 (0.81–3.82)[126][127][115][117]DAS28-4(ESR) moderate/high disease activity3.56 (1.17–7.13)3.58 (1.36–8.33)2.60 (0.87–5.16)2.68 (1.34–8.23)[107][107][115][115]

aMean CRP was calculated as the average CRP value during each time period (>BL–W24 or >W24–48)

CRP, C-reactive protein; DAS28-4(ESR), Disease Activity Score in 28 joints, erythrocyte sedimentation rate; HAQ-DI, Health Assessment Questionnaire-Disability Index; IQR, interquartile range; LDA, low disease activity; MTX, methotrexate; n, number of pts meeting assessment criteria; QD, once daily

Conclusion:

Although clinical/functional responses were generally similar between treatment groups, numerical improvements were seen for some efficacy endpoints with tofacitinib + MTX vs tofacitinib + PBO. A numerically higher CRFP rate may be associated with higher DAS28-4(ESR) disease activity. CRP changes up to W48 may not trend with CRFP status.

References:

[1]Cohen et al. Lancet Rheumatol 2019; 1: E23-34.

Acknowledgements:

Study sponsored by Pfizer Inc. Medical writing support was provided by Anthony G McCluskey, CMC Connect, and funded by Pfizer Inc.

Disclosure of Interests:

Stanley B. Cohen Consultant of: AbbVie, Eli Lilly, Genentech, Gilead Sciences, Pfizer Inc, Grant/research support from: AbbVie, Eli Lilly, Genentech, Gilead Sciences, Pfizer Inc, Yi-Hsing Chen Grant/research support from: Bristol-Myers Squibb, GlaxoSmithKline, Pfizer Inc, Naonobu Sugiyama Shareholder of: Pfizer Inc, Employee of: Pfizer Inc, Jose Luis Rivas Shareholder of: Pfizer Inc, Employee of: Pfizer Inc, Annette Diehl Shareholder of: Pfizer Inc, Employee of: Pfizer Inc, Tatjana Lukic Shareholder of: Pfizer Inc, Employee of: Pfizer Inc, Jerome Paulissen Consultant of: Pfizer Inc, Haiyun Fan Shareholder of: Pfizer Inc, Employee of: Pfizer Inc, Tomohiro Hirose Shareholder of: Pfizer Inc, Employee of: Pfizer Inc, Edward Keystone Speakers bureau: AbbVie, Amgen, F. Hoffman-La Roche, Janssen, Merck, Novartis, Pfizer Inc, Sanofi Genzyme, Consultant of: AbbVie, Amgen, Bristol-Myers Squibb, Celltrion, Eli Lilly, F. Hoffman-La Roche, Gilead Sciences, Janssen, Merck, Myriad Autoimmune, Pfizer Inc, Sandoz, Sanofi Genzyme, Samsung Bioepsis, Grant/research support from: Amgen, Merck, Pfizer Inc, PuraPharm

POS0650 PREDICTORS OF DURABLE CLINICAL RESPONSE TO TOFACITINIB 11 MG ONCE DAILY WITH OR WITHOUT METHOTREXATE IN PATIENTS WITH RHEUMATOID ARTHRITIS: POST HOC ANALYSIS OF DATA FROM A PHASE 3b/4 METHOTREXATE WITHDRAWAL STUDY

Background:

ORAL Shift, a global Phase 3b/4 non-inferiority study, demonstrated sustained efficacy and safety of tofacitinib modified-release (MR) 11 mg once daily (QD) following methotrexate (MTX) withdrawal in patients with rheumatoid arthritis (RA) who achieved Clinical Disease Activity Index (CDAI) low disease activity (LDA) after treatment with tofacitinib + MTX.1

Objectives:

To assess predictors of durable clinical response in patients receiving tofacitinib MR 11 mg QD in ORAL Shift.

Methods:

ORAL Shift (NCT02831855) enrolled patients aged ≥18 years with moderate to severe RA and an inadequate response to MTX. Patients received open-label tofacitinib MR 11 mg QD + MTX for 24 weeks. Patients achieving LDA (CDAI score ≤10) at Week (W)24 entered the 24-week double-blind MTX withdrawal phase and were randomised 1:1 to receive tofacitinib MR 11 mg QD + placebo (tofacitinib monotherapy; ie blinded MTX withdrawal) or continue tofacitinib + MTX. In this post hoc analysis of randomised patients, we assessed predictors of durable response (maintenance of response from W24–48) per CDAI LDA and remission (CDAI score ≤2.8) criteria. All covariates were initially assessed for significance in a univariate logistic regression. Highly correlated covariates were reviewed to assess which would be removed prior to modelling in a multivariable logistic regression. Remaining significant (p≤0.10) covariates in the univariate regression were selected in the model using a stepwise selection process with p≤0.15 entry and p≤0.05 stay criteria. From the final model, estimated odds ratios (ORs) with 95% confidence intervals (CIs) are presented.

Results:

In the double-blind phase of ORAL Shift, durable CDAI LDA and remission rates were: 66.2% and 14.7%, respectively, with tofacitinib + MTX (N=266); and 55.3% and 11.0%, respectively, with tofacitinib + placebo (N=264) (Table 1). In the multivariable analysis, five patient covariates significantly predicted durable CDAI LDA (Figure 1; discussed hereafter). Each unit increase in CDAI score at W24 reduced the likelihood of maintaining CDAI LDA by 22.0%. Each unit increase in C-reactive protein (CRP) at W24 increased the likelihood of maintaining CDAI LDA by 4.0%; this may have been due to imbalanced CRP levels at W24 (randomisation) between treatment groups (Figure 1, footnote c). The odds of durable CDAI LDA were 53.0% lower in the US vs Europe and 61.0% lower in the US vs ‘other’ regions. Each unit increase in baseline Health Assessment Questionnaire-Disability Index (HAQ-DI) score reduced the odds of durable CDAI LDA by 34.0%. Patients receiving tofacitinib + MTX had 66.0% greater odds of durable CDAI LDA vs patients receiving tofacitinib + placebo. CDAI at W24 was the only significant predictor of durable CDAI remission in the multivariable analysis: OR (95% CI) 0.32 (0.24, 0.43); p<0.0001. Each unit increase in CDAI score at W24 reduced the odds of durable CDAI remission by 68.0%.

Table 1.

Durable CDAI LDA and remissiona in patients receiving tofacitinib MR 11 mg QD with MTX or placebo in the double-blind phase of ORAL Shift

Tofacitinib + MTX(N=266)Tofacitinib + placebo(N=264)Durable CDAI LDA, n (%)176 (66.2)146 (55.3)Durable CDAI remission, n (%)39 (14.7)29 (11.0)

aDurable CDAI LDA or remission was defined as achievement of LDA (CDAI score ≤10) or remission (CDAI score ≤2.8), respectively, at W24–48

N, number of patients in each group; n, number of patients achieving outcome

Conclusion:

This post hoc analysis of data from ORAL Shift found that CDAI and CRP at W24, geographic region, baseline HAQ-DI and treatment could be predictors for durable CDAI LDA. As these findings were limited to patients who achieved CDAI LDA at W24 with tofacitinib MR 11 mg QD + MTX, additional data in the general patient population need to be investigated.

References:

[1]Cohen et al. Lancet Rheumatol 2019; 1: E23-34.

Acknowledgements:

Study sponsored by Pfizer Inc. Medical writing support was provided by Sarah Piggott, CMC Connect, and funded by Pfizer Inc.

Disclosure of Interests:

Kunihiro Yamaoka Speakers bureau: Actelion, Astellas, Chugai, Eisai, Eli Lilly, GlaxoSmithKline, Janssen, Mitsubishi Tanabe, Nippon Shinyaku, Pfizer Inc, Takeda, Consultant of: Actelion, Astellas, Chugai, Eisai, Eli Lilly, GlaxoSmithKline, Janssen, Mitsubishi Tanabe, Nippon Shinyaku, Pfizer Inc, Takeda, Stanley B. Cohen Consultant of: AbbVie, Eli Lilly, Genentech, Gilead Sciences, Pfizer Inc, Grant/research support from: AbbVie, Eli Lilly, Genentech, Gilead Sciences, Pfizer Inc, Naonobu Sugiyama Shareholder of: Pfizer Inc, Employee of: Pfizer Inc, Harry Shi Shareholder of: Pfizer Inc, Employee of: Pfizer Inc, Jose Luis Rivas Shareholder of: Pfizer Inc, Employee of: Pfizer Inc, Annette Diehl Shareholder of: Pfizer Inc, Employee of: Pfizer Inc, Josef S. Smolen Consultant of: AbbVie, AstraZeneca, Celgene, Celltrion, Chugai, Eli Lilly, Gilead Sciences, ILTOO, Janssen, Novartis-Sandoz, Pfizer Inc, Roche, Samsung, Sanofi, Grant/research support from: AbbVie and AstraZeneca

Validity of claims-based algorithms for selected cancers in Japan: Results from the VALIDATE-J study

Purpose

Real‐world data from large administrative claims databases in Japan have recently become available, but limited evidence exists to support their validity. VALIDATE‐J validated claims‐based algorithms for selected cancers in Japan.

Methods

VALIDATE‐J was a multicenter, cross‐sectional, retrospective study. Disease‐identifying algorithms were used to identify cancers diagnosed between January or March 2012 and December 2016 using claims data from two hospitals in Japan. Positive predictive values (PPVs), specificity, and sensitivity were calculated for prevalent (regardless of baseline cancer‐free period) and incident (12‐month cancer‐free period; with claims and registry periods in the same month) cases, using hospital cancer registry data as gold standard.

Results

22 108 cancers were identified in the hospital claims databases. PPVs (number of registry cases) for prevalent/incident cases were: any malignancy 79.0% (25 934)/73.1% (18 119); colorectal 84.4% (3519)/65.6% (2340); gastric 87.4% (3534)/76.8% (2279); lung 88.1% (2066)/79.9% (1636); breast 86.4% (4959)/59.9% (3185); pancreatic 87.1% (582)/80.4% (508); melanoma 48.7% (46)/42.9% (36); and lymphoma 83.6% (1457)/77.8% (1035). Specificity ranged from 98.3% to 100% (prevalent)/99.5% to 100% (incident); sensitivity ranged from 39.1% to 67.6% (prevalent)/12.5% to 31.4% (incident). PPVs of claims‐based algorithms for several cancers in patients ≥66 years of age were slightly higher than those in a US Medicare population.

Conclusions

VALIDATE‐J demonstrated high specificity and modest‐to‐moderate sensitivity for claims‐based algorithms of most malignancies using Japanese claims data. Use of claims‐based algorithms will enable identification of patient populations from claims databases, while avoiding direct patient identification. Further research is needed to confirm the generalizability of our results and applicability to specific subgroups of patient populations.

OP0187 INCIDENCE OF MALIGNANCY IN JAPANESE PATIENTS WITH RHEUMATOID ARTHRITIS: DATA FROM THE JAPANESE IORRA PATIENT REGISTRY

Background:

The risk of some types of malignancy is increased in patients (pts) with rheumatoid arthritis (RA), compared with the general population. We have previously reported the incidence of malignancy in Japanese pts with RA.1-4

Objectives:

This analysis further evaluated the incidence of malignancy in Japanese pts with RA using recent data from the large prospective observational study, IORRA.

Methods:

This analysis included all pts with RA aged ≥18 years who were enrolled in IORRA from April 2013 to October 2018, with follow-up through October 2019, and participated in ≥2 surveys. Index was defined as the date of the first entry in the IORRA database, with baseline defined as the 6-month period prior to the index date. Malignancies were identified in pt reports of biannual IORRA surveys and confirmed using medical records. Age- and sex-standardised incidence ratios (SIRs) and 95% confidence intervals (CIs) were calculated.

Results:

In total, 8020 pts were included. At baseline, the majority (85.0%) of pts were female; mean disease duration was 12.8 years, 5.8% and 4.8% of pts had a past history of malignancy or comorbid malignancy at baseline, respectively, and the majority (75.9%) of pts were receiving methotrexate (Table). The SIR (95% CI) was 0.90 (0.80, 1.01). SIRs (95% CI) of site-specific malignancies were: breast cancer, 0.91 (0.69, 1.18); lung cancer, 0.67 (0.44, 0.97); colon cancer, 0.93 (0.62, 1.32); stomach cancer, 0.82 (0.56, 1.14); and lymphoma, 3.74 (2.73, 4.96).

Table 1.

Patient demographics and baseline disease characteristics

Patients with RA (N=8020)Age (years), mean (SD)59.3 (13.8)Female, n (%)6816 (85.0)Duration of RA (years), mean (SD)12.8 (10.3)Never smoked, n (%)5086 (66.2)DAS28, mean (SD)2.8 (1.1)J-HAQ, mean (SD)0.60 (0.72)Malignancy status, n (%)Past history of malignancy467 (5.8)Comorbid malignancy at baseline386 (4.8)Medication use, n (%)MTX6088 (75.9)Tacrolimus787 (9.8)Corticosteroids2641 (32.9)bDMARD use1508 (18.8)TNFi1163 (14.5)Tocilizumab311 (3.9)Abatacept106 (1.3)JAK inhibitors4 (0.05)

bDMARD, biological disease-modifying antirheumatic drug; DAS28, Disease Activity Score in 28 joints; JAK, Janus kinase; J-HAQ, Japanese Health Assessment Questionnaire; MTX, methotrexate; N, the number of patients included in the analysis, the number of patients assessed for each characteristic may be fewer than N; n, the number of patients with each characteristic; SD, standard deviation; TNFi, tumour necrosis factor inhibitor

Conclusion:

Overall risk of malignancy was similar to that in the general Japanese population, although a significantly higher risk of lymphoma was identified.

References:

[1]Sugimoto et al. Rheumatol Int 2017; 37: 1871-1878.

[2]Shimizu et al. Clin Rheumatol 2017; 36: 1237-1245.

[3]Askling et al. Ann Rheum Dis 2016; 75: 1789-1796.

[4]Yamada et al. Rheumatol Int 2011; 31: 1487-1492.

Acknowledgements:

Study sponsored by Pfizer Inc. Medical writing support was provided by Anthony G McCluskey, CMC Connect, and funded by Pfizer Inc.

Disclosure of Interests:

masayoshi harigai Speakers bureau: AbbVie Japan, Ayumi, Boehringer Ingelheim Japan, Bristol-Myers Squibb, Chugai, Eisai, Eli Lilly Japan, GlaxoSmithKline, Kissei, Pfizer Japan Inc, Takeda, Teijin, Consultant of: AbbVie Japan, Boehringer Ingelheim Japan, Bristol-Myers Squibb, Kissei, Teijin, Grant/research support from: AbbVie Japan, Asahi Kasei, Astellas, Ayumi, Bristol-Myers Squibb, Chugai, Daiichi-Sankyo, Eisai, Kissei, Mitsubishi Tanabe, Nippon Kayaku, Sekiui Medical, Shionogi, Taisho, Takeda, Teijin, Naohiro Sugitani: None declared, Ryoko Sakai Speakers bureau: Bristol-Myers Squibb, Eisuke Inoue Speakers bureau: Pfizer Japan Inc, Bristol-Myers Squibb, Michika MOCHIZUKI Shareholder of: Pfizer Inc, Employee of: Pfizer Inc, Shigeyuki Toyoizumi Employee of: Pfizer R&D Japan, Noritoshi Yoshii Shareholder of: Pfizer Inc, Employee of: Pfizer Inc, Naonobu Sugiyama Shareholder of: Pfizer Inc, Employee of: Pfizer Inc, Eiichi Tanaka Speakers bureau: AbbVie Japan, Asahi Kasei, Astellas, Ayumi, Chugai, Eisai, Eli Lilly Japan, GlaxoSmithKline, Kyowa, Janssen, Mochida, Pfizer Japan Inc, Takeda, Teijin, Hisashi Yamanaka Speakers bureau: Astellas, Bristol-Myers-Squibb, Pfizer Inc, Mitsubishi Tanabe, Teijin, YLBio, Consultant of: Corrona, LLC

POS0286 INCIDENCE OF MALIGNANCIES IN JAPANESE PATIENTS WITH RHEUMATOID ARTHRITIS: DATA FROM A LARGE JAPANESE NATIONAL REGISTRY

Background:

Patients (pts) with rheumatoid arthritis (RA) have an increased risk of some malignancies vs the general population, and this can vary by region/race.1,2 Data on the epidemiology and impact of biological (b)DMARDs and targeted synthetic (ts)DMARDs, such as Janus kinase (JAK) inhibitors, on the incidence of malignancies in Japanese pts with RA are limited. The National Database of Rheumatic Diseases in Japan (NinJa) is one of the largest RA registries in Japan.

Objectives:

To evaluate the incidence of malignancies in Japanese pts with RA using NinJa registry data.

Methods:

This retrospective observational study analysed NinJa registry data for Japanese pts with RA aged ≥18 years with ≥1 data entry between 2013 (first JAK inhibitor approval for RA in Japan) and 2018. The overall cohort included all pts with RA, and two sub-cohorts were analysed: pts exposed and unexposed to bDMARDs (exposure defined as ≥1 bDMARD reported in database). Crude incidence rates (IRs) for malignancies (including non-melanoma skin cancer) were calculated as the number of events per 100 pt-years of follow-up (time between start of follow-up or the date of first bDMARD exposure [for bDMARD-exposed pts] and end of observation period, or withdrawal from database). The most recent data for incidence of malignancy in the Japanese general population (2013–2017 data from the National Cancer Center, Japan) were used to calculate standardised incidence ratios (SIRs) and age- and sex-adjusted standardised rates (ASRs) for malignancies. Cross-sectional (per calendar year) and cumulative analyses were performed for the overall cohort. Cumulative rates were calculated for sub-cohorts, and all cumulative analyses were repeated excluding pts exposed to JAK inhibitors (ie ≥1 JAK inhibitor reported in database).

Results:

Data were collected for 26 607 Japanese pts with RA from 2013–2018. In the cross-sectional analysis (Table 1), the SIR and ASR for malignancies in all pts with RA were generally consistent from 2013–2018. In the cumulative analysis, the SIR (95% CI) for malignancies from 2013–2018 was 0.97 (0.91, 1.03) in all pts with RA, and 0.93 (0.82, 1.04) and 0.99 (0.92, 1.07) in pts exposed and unexposed to bDMARDs, respectively (Figure 1). Adjusting for age/sex, the cumulative ASR (95% CI) for malignancies from 2013–2018 was 0.83 (0.76, 0.90) in all pts with RA, and 0.82 (0.69, 0.95) and 0.86 (0.77, 0.96) in pts exposed and unexposed to bDMARDs, respectively (Figure 1). In all cohorts, the cumulative SIR and ASR were similar when pts exposed to JAK inhibitors were excluded (Figure 1).

Table 1.

Cross-sectional analysis of the incidence of malignancies in Japanese pts with RA from 2013–2018

All RA2013 (N=13 423)2014 (N=15 584)2015 (N=15 751)2016 (N=16 107)2017 (N=15 994)2018(N=15 003)Total follow-up, PY13 35314 86614 82914 97014 74814 898Pts with events, n140164174168161211Crude IRa(95% CI)1.05(0.89, 1.24)1.10(0.95, 1.29)1.17(1.01, 1.36)1.12(0.97, 1.31)1.09(0.94, 1.27)1.42(1.24, 1.62)ASRa,b(95% CI)0.76(0.60, 0.93)0.76(0.62, 0.90)0.90(0.68, 1.11)0.88(0.68, 1.07)0.80(0.62, 0.98)0.88(0.74, 1.01)SIRb(95% CI)0.97(0.82, 1.14)1.01(0.86, 1.17)1.02(0.87, 1.18)0.88(0.75, 1.02)0.86(0.73, 1.00)1.10(0.95, 1.25)

aIR/ASR were calculated as number of events per 100 PY of follow-up

bData from a Japanese general population database of malignancy incidence from 2013–2017, provided by the Center for Cancer Control and Information Services, National Cancer Center, Japan

PY, pt-years

Conclusion:

The incidence of malignancies in Japanese pts with RA, registered in the NinJa database from 2013–2018, was similar to that in the Japanese general population. The SIR and ASR for malignancies were comparable in pts exposed and unexposed to bDMARDs. In all cohorts, rates did not increase when pts exposed to JAK inhibitors were included.

References:

[1] Dougados et al. Ann Rheum Dis 2014; 73: 62-68.

[2] Parikh-Patel et al. Cancer Causes Control 2009; 20: 1001-1010.

Acknowledgements:

Study sponsored by Pfizer Inc. Medical writing support was provided by Christina Viegelmann, CMC Connect, and funded by Pfizer Inc.

Disclosure of Interests:

Toshihiro Matsui Speakers bureau: Astellas, Ayumi, Chugai, Daiichi-Sankyo, Eli Lilly, Ono, Pfizer Inc, Takeda, Tanabe-Mitsubishi, Consultant of: Pfizer Inc, Grant/research support from: Chugai, Naonobu Sugiyama Shareholder of: Pfizer Inc, Employee of: Pfizer Inc, Shigeyuki Toyoizumi Employee of: Pfizer R&D Japan, Fujio Matsuyama Consultant of: Pfizer Inc, Employee of: CRECON Medical Assessment Inc, Tatsunori Murata Consultant of: Pfizer Inc, Employee of: CRECON Medical Assessment Inc, Yukitomo Urata Speakers bureau: Asahi Kasei, Chugai, Eli Lilly, Pfizer Inc, Consultant of: AbbVie, Asahi Kasei, Chugai, Pfizer Inc, Kimito Kawahata Speakers bureau: Pfizer Inc, Consultant of: Pfizer Inc, Grant/research support from: Pfizer Inc, Shigeto Tohma Speakers bureau: Astellas, Ayumi, Chugai, Ono, Pfizer Inc, Takeda, Consultant of: Pfizer Inc

Modified- versus immediate-release tofacitinib in Japanese rheumatoid arthritis patients: a randomized, phase III, non-inferiority study

Objective

Tofacitinib is an oral Janus kinase inhibitor for treatment of RA. We compared tofacitinib modified-release (MR) 11 mg once daily (QD) with tofacitinib immediate-release (IR) 5 mg twice daily (BID) in Japanese patients with RA and inadequate response to MTX.

Methods

Phase III, randomized, double-blind, double-dummy, 12-week study. Patients were randomized to tofacitinib MR 11 mg QD (n = 104) or IR 5 mg BID (n = 105), with stable MTX. Compliance was based on returned pill counts. The primary objective was to demonstrate non-inferiority of MR 11 mg QD to IR 5 mg BID. Non-inferiority was declared if the upper bound of the two-sided 95% CI for the difference in change from baseline in DAS28-4(CRP) at week 12 was <0.6.

Results

At week 12, with tofacitinib MR 11 mg QD and IR 5 mg BID, respectively, the change from baseline in least squares mean DAS28-4(CRP) was −2.43 and −2.85; the mean difference was 0.43 (95% CI 0.17, 0.69). Non-inferiority of MR 11 mg QD to IR 5 mg BID was not met. Improvement of DAS28-4(CRP) ⩾1.2 was observed in 89 and 85% of patients, respectively, corresponding to a clinically important, significant change in both groups. The frequency of adverse events (52.9 and 51.4%, respectively) and serious adverse events (4.8 and 3.8%, respectively) was generally similar between treatments. No deaths were reported.

Conclusion

Non-inferiority of MR 11 mg QD to IR 5 mg BID was not met in this study. However, clinically meaningful improvements in RA were observed with both tofacitinib formulations in Japanese patients. The safety profile was similar with both formulations.

Trial registration

ClinicalTrials.gov, http://clinicaltrials.gov, NCT02281552.

Efficacy and safety of tofacitinib for the treatment of rheumatoid arthritis in patients from the Asia-Pacific region: Post-hoc analyses of pooled clinical study data

AIM

We report tofacitinib efficacy and safety in Asia-Pacific patients who participated in the rheumatoid arthritis (RA) clinical development program.

METHOD

This post-hoc analysis included pooled data from patients with RA in the Asia-Pacific region treated with tofacitinib with/without conventional synthetic disease-modifying antirheumatic drugs in Phase (P)1, 2, 3, and long-term extension (LTE) studies (one LTE ongoing; January 2016 data-cut). Efficacy was assessed over 24 months in patients who received tofacitinib 5 (N = 397) or 10 (N = 382) mg twice daily or placebo (N = 243) in three P2 and five P3 studies. Endpoints included American College of Rheumatology (ACR)20/50/70 responses, Disease Activity Score in 28 joints, erythrocyte sedimentation rate (DAS28-4[ESR]) and Clinical Disease Activity Index (CDAI) remission rates, and change from baseline in Health Assessment Questionnaire-Disability Index (∆HAQ-DI). Safety data pooled over 92 months from one P1, four P2, six P3, and two LTE studies for all tofacitinib doses (N = 1464) included incidence rates (IRs) (patients with events/100 patient-years) for adverse events (AEs) of special interest.

RESULTS

At month 3, patients receiving tofacitinib 5/10 mg twice daily improved vs placebo in ACR20 (69.2%/77.9% vs 27.5%), ACR50 (36.9%/44.4% vs 9.5%), and ACR70 (15.1%/22.4% vs 2.7%) responses, remission rates for DAS28-4(ESR) (8.5%/18.5% vs 2.6%) and CDAI (6.1%/12.3% vs 0.5%), and ∆HAQ-DI (-0.5/-0.6 vs -0.1); improvements were sustained through 24 months. IRs (95% CI) were 9.4 (8.5, 10.3) for serious AEs, 9.1 (8.3, 10.1) for discontinuations due to AEs, 3.7 (3.2, 4.3) for serious infections, 5.9 (5.2, 6.7) for herpes zoster, and 0.8 (0.6, 1.1) for malignancies (excluding non-melanoma skin cancer).

CONCLUSION

In Asia-Pacific patients, tofacitinib improved signs/symptoms over 24 months. Safety over 92 months was generally consistent with global tofacitinib studies; however, infection IRs were higher in Asia-Pacific patients.

Efficacy and safety of tofacitinib in Japanese patients with rheumatoid arthritis by background methotrexate dose: A post hoc analysis of clinical trial data

Objectives: Tofacitinib is an oral JAK inhibitor for the treatment of rheumatoid arthritis (RA). We investigated concomitant methotrexate (MTX) dose on tofacitinib efficacy/safety in Japanese RA patients. Methods: This post hoc analysis pooled data from a 3-month phase 2 study (NCT00603512) and a 24-month phase 3 study (NCT00847613). Patients (N= 254) received tofacitinib (low-dose (1 or 3 mg), 5 mg, 10 mg) twice daily (BID) or placebo, with low-dose (>0 to 8 mg/week) or high-dose (>8 mg/week) MTX. Efficacy (ACR20/50/70 and DAS28-4 (ESR)<2.6 response rates; changes from baseline (CFB) in DAS28-4 (ESR) and HAQ-DI) and safety (adverse events (AEs), discontinuations due to AEs, serious AEs, and deaths) were assessed through month 3. Results: At month 3, ACR20/50/70 response rates, mean DAS28-4 (ESR) CFB and HAQ-DI CFB were similar across MTX doses and generally greater for all tofacitinib doses versus placebo. AE rates with low-dose/high-dose MTX were: placebo, 28.6%/52.9%; tofacitinib low-dose, 50.0%/66.7%; 5 mg BID, 56.5%/64.3%; 10 mg BID, 73.8%/67.7%. Conclusion: Tofacitinib efficacy in Japanese RA patients may be unaffected by background MTX dose. AE rates with low-dose versus high-dose MTX were lower with placebo, tofacitinib low-dose or 5 mg BID, but not 10 mg BID, with no apparent differences across system organ class/laboratory parameters.

Three-year safety and two-year effectiveness of etanercept in patients with rheumatoid arthritis in Japan: Results of long-term postmarketing surveillance

Objectives: To evaluate the real-world safety and effectiveness of etanercept (ETN) in Japanese patients with rheumatoid arthritis. Methods: This postmarketing surveillance study (NCT00503139) assessed the safety and effectiveness of ETN treatment over 3 and 2 years (from June 2007 to September 2011), respectively. Safety was evaluated by occurrence and seriousness of adverse drug reactions (ADRs), and of adverse events (AEs) for malignancies. Effectiveness was assessed using the Disease Activity Score in 28 joints based on the erythrocyte sedimentation rate (ESR) with four variables (swollen and tender joint counts, ESR, and patient global assessment; DAS28-4/ESR). Treatment was considered effective if patients had a good/moderate response by the European League Against Rheumatism response criteria. Results: ADRs occurred in 256/675 (37.9%) patients, the most common being injection site reactions (4.4%) and nasopharyngitis (3.3%). Serious ADRs occurred in 60/675 (8.9%) patients, the most frequent being pneumonia (1.2%). The incident rate of malignancies (AEs) was 1.06 per 100 patient-years. Mean baseline DAS28-4/ESR for the 581 patients included in effectiveness analysis was 5.42, which decreased to 3.32 at 2 years. Eighty-two percent of patients achieved a moderate/good response at 2 years. Conclusion: Long-term ETN treatment safety and effectiveness were sustained over 3 and 2 years, respectively.

Abstract PD5-03: TransNEOS: Validation of the oncotype DX recurrence score (RS) testing core needle biopsy samples from NEOS as predictor of clinical response to neoadjuvant endocrine therapy for postmenopausal estrogen receptor positive (ER+), HER2 negative (HER2-) breast cancer patients

Background: Neoadjuvant therapy for locally advanced breast cancer has the potential to improve surgical therapeutic outcomes without sacrificing the survival advantages of adjuvant therapy. However, determining whether ER+ patients (pts) will respond to neoadjuvant (NA) chemotherapy (CT) or hormone therapy (HT) can be difficult. Not all ER+ pts respond to NACT, while response to NAHT can vary across ER+ pts. Thus, the ability to select pts more likely to benefit from NAHT would represent progress in clinical management of breast cancer. NEOS is a randomized phase III study assessinglong-term prognosis of ER+ primary breast cancer with/without adjuvant CT following NAHT (UMIN 000001090, http://www.umin.ac.jp/). We used archived core biopsy tumor samples from the NEOS study to validate the RS result as a predictor of clinical response and its association with successful breast conserving surgery (BCS) in pts treated with 6 months of NAHT.

Methods: NEOS enrolled 904 postmenopausal pts with ER+, HER2-, clinically node negative (cN0) breast cancer to evaluate whether adjuvant CT was necessary for pts who responded to NAHT. In this current study, we enrolled pts with tumors ≥2cm from the NEOS study. Biopsy samples of 333 pts were assessed for the Oncotype DX assay. Response to NAHT was recorded as complete/partial response (CR/PR), or stable/progressive disease (SD/PD).

Primary endpoint of this study was to evaluate clinical response (CR/PR) to NA letrozole between pts with low (&lt;18) and high (≥31) RS result. Secondary endpoints include evaluating the relationships between clinical response and continuous RS results, and other covariates including age, tumor size, grade, Ki67 by IHC, ER and PR single gene scores, and ER and proliferation gene group scores by RT-PCR.

Results: The analysis included 294 pts with median age of 63 yrs, median tumor size of 25mm, and 66% were nuclear grade 1. 156 (53.0%), 83 (28.6%) and 54(18.4%) cases were low, intermediate, and high RS groups by Oncotype DX, respectively. Six (2%), 126 (42.8%), 149 (50.3%), 13 (4.4%) cases experienced CR, PR, SD, PD as clinical response, respectively, similar to that of all NEOS pts. Clinical response rate was 54%, 42% and 22% in low, intermediate, and high RS groups, respectively. The proportion of pts with clinical response was significantly higher in the low RS group vs the high RS group (p&lt;0.001). In univariate analyses, continuous RS was significantly associated with clinical response (p&lt;0.001), along with ER (p=.02), PR (p&lt;0.001), and ER gene group score (p&lt;0.001). Other covariates were not associated with clinical response.

Conclusion: The Oncotype DX RS test in core biopsy samples is validated as a predictive assay for clinical response of NAHT in postmenopausal, ER+/HER2-, cN0, primary early breast cancer pts. Further results on the association of RS results with BCS outcomes following NAHT will be presented. These results when combined with previously published data on RS in NACT studies help guide pts with ER+, HER2- breast cancer with NAHT vs NACT treatment options to maximize clinical response.

Citation Format: Yamamoto Y, Iwata H, Masuda N, Fujisawa T, Toyama T, Kashiwaba M, Ohtani S, Taira N, Sakai T, Hasegawa Y, Nakamura R, Akabane H, Shibahara Y, Sasano H, Yamaguchi T, Sakamaki K, Chao C, McCullough D, Sugiyama N, Ohashi Y. TransNEOS: Validation of the oncotype DX recurrence score (RS) testing core needle biopsy samples from NEOS as predictor of clinical response to neoadjuvant endocrine therapy for postmenopausal estrogen receptor positive (ER+), HER2 negative (HER2-) breast cancer patients [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr PD5-03.

Safety and effectiveness of etanercept for treatment of juvenile idiopathic arthritis: Results from a postmarketing surveillance

OBJECTIVES

The objectives of this surveillance were to determine safety and effectiveness of etanercept in patients with juvenile idiopathic arthritis (JIA).

METHODS

In this postmarketing surveillance, patients aged 5-16 years with active polyarthritis JIA were treated with etanercept at the doses approved in the Japanese package insert. The occurrence and seriousness of adverse events (AEs) were assessed using the Japanese Medical Dictionary for Regulatory Activities version 15.1. Effectiveness was determined as the improvement from baseline in disease activity score in 28 joints (DAS28)-erythrocyte sedimentation rate (ESR), remission, and physician's assessment of overall improvement. The number of responders was expressed as a percentage. The last observation carried forward method was used to impute missing data.

RESULTS

Safety analysis included 102 patients; 22 patients experienced 36 treatment-related AEs, three of which were unexpected. None of the AEs were deemed to need special safety warnings. Effectiveness analysis included 87 patients. At 24 weeks, 29/46 (63.0%) patients demonstrated either good or moderate response in DAS28-4/ESR and treatment was assessed to be markedly effective or effective by physicians in 79/83 (95.2%) patients.

CONCLUSIONS

These data are consistent with earlier reports showing that etanercept was effective and demonstrated no safety signals in patients with JIA.

Obstetrical correlates and perinatal consequences of neonatal hypoglycemia in term infants

OBJECTIVE

To determine independent perinatal and intrapartum factors associated with neonatal hypoglycemia.

METHOD

Of singleton pregnancies delivered at term in 2013; 318 (3.8%) neonates diagnosed with hypoglycemia were compared to 7955 (96.2%) neonate controls with regression analysis.

RESULTS

Regression analysis showed that independent prenatal factors were multiparity (odds-ratio [OR] = 1.61), gestational age (OR = 0.68), gestational diabetes (OR = 0.22), macrosomia (OR = 4.87), small for gestational age neonate [SGA] (OR = 6.83) and admission cervical dilation (OR = 0.79). For intrapartum factors, only cesarean section (OR = 1.57) and last cervical dilation (OR = 0.92) were independently significantly associated with neonatal hypoglycemia. For biologically plausible risk factors, independent factors were cesarean section (OR = 4.18), gentamycin/clindamycin in labor (OR = 5.35), gestational age (OR = 0.59) and macrosomia (OR = 5.62). Mothers of babies with neonatal hypoglycemia had more blood loss and longer hospital stays, while neonates with hypoglycemia had worse umbilical cord gases, more neonatal hypoxic conditions, neonatal morbidities and NICU admissions.

CONCLUSION

Diabetes was protective of neonatal hypoglycemia, which may be explained by optimum maternal glucose management; nevertheless macrosomia was independently predictive of neonatal hypoglycemia. Cesarean section and decreasing gestational age were the most consistent independent risk factors followed by treatment for chorioamnionitis and SGA. Further studies to evaluate these observations and develop preventive strategies are warranted.

Treatment Patterns, Direct Cost of Biologics, and Direct Medical Costs for Rheumatoid Arthritis Patients: A Real-world Analysis of Nationwide Japanese Claims Data

PURPOSE

The aims of this article were to characterize the patterns of treating rheumatoid arthritis with biologics and to evaluate costs using claims data from the Japan Medical Data Center Co, Ltd.

METHODS

Patients aged 16 to <75 years who were diagnosed with rheumatoid arthritis and prescribed adalimumab (ADA), etanercept (ETN), infliximab (IFX), tocilizumab (TCZ), abatacept, certolizumab, or golimumab between January 2005 and August 2014 were included. For the cross-sectional analysis, the annual costs of ETN, IFX, ADA, and TCZ from 2009 to 2013 were assessed. For the longitudinal analysis, patients prescribed these biologics as the first line of biologics, from January 2005 to August 2014, were included. The cost of biologic treatment over 1, 2, and 3 years (including prescription of subsequent biologics) and direct medical costs (including treatment of comorbidities) were compared between groups. Discontinuation and switching rates in each group were estimated, and multivariate analyses were conducted to estimate an adjusted hazard ratio of discontinuation and switching rates among each group. The dose of each first-line biologic treatment until discontinuation was analyzed to calculate relative dose intensity.

FINDINGS

The cross-sectional annual biologic costs of ETN, IFX, ADA, and TCZ were ~$8000 (2009 and 2013), $13,000 (2009) and $15,000 (2013), $10,000 (2009) and $11,000 (2013), and $9000 (2009) and $8000 (2013), respectively. In longitudinal analyses (n = 764), 276 (36%) initiated ETN; 242 (32%), IFX; 147 (19%), ADA; and 99 (13%), TCZ. The 1-year cumulative annual biologic costs per patient from the initial prescription of ETN, IFX, ADA, and TCZ as the first-line biologic treatment were ~$11,000, $19,000, $16,000, and $12,000. The corresponding direct medical costs over 1 year from the initial prescription were ~$17,000, $26,000, $22,000, and $22,000. Costs remained greatest in the IFX-initiation group at year 3. The discontinuation rates at 36 months with ETN, IFX, ADA, and TCZ were 37.7%, 52.3%, 55.8%, and 39.5%; the switching rates were 12.5%, 27.1%, 31.0%, and 16.7%. The mean (95% CI) relative dose intensities until discontinuation of ETN 25 mg, ETN 50 mg, IFX, ADA, and TCZ were 1.02 (0.95-1.10), 0.82 (0.79-0.85), 1.16 (1.12-1.20), 0.95 (0.90-0.99), and 0.96 (0.93-1.00).

IMPLICATIONS

Considered costs and discontinuation and switching event rates were lowest with ETN versus IFX, ADA, or TCZ used as the first-line biologic. Despite limitations, these findings imply clinical cost-reductive benefits of ETN as the first-line biologic treatment option for rheumatoid arthritis in Japan.

Tofacitinib, an oral Janus kinase inhibitor, as monotherapy or with background methotrexate, in Japanese patients with rheumatoid arthritis: an open-label, long-term extension study

Background

Tofacitinib is an oral Janus kinase inhibitor for the treatment of rheumatoid arthritis. Here, tofacitinib safety and efficacy data from a long-term extension study in Japanese patients are presented.

Methods

Study A3921041 was a multi-centre, open-label, long-term extension study that included Japanese patients who had participated in a prior Phase 2 or Phase 3 study of tofacitinib as monotherapy or with background methotrexate. Patients received tofacitinib 5 mg twice daily (BID) or tofacitinib 10 mg BID. Dose adjustment of tofacitinib during treatment period, and concomitant usage of disease-modifying antirheumatic drugs including methotrexate after week 12 were permitted. Primary endpoints were adverse events, laboratory parameters and vital signs. Secondary efficacy endpoints included American College of Rheumatology (ACR)20/50/70 response rates, Disease Activity Score (DAS)28-4(erythrocyte sedimentation rate (ESR))<2.6 response rate (DAS-defined remission) and Health Assessment Questionnaire-Disability Index (HAQ-DI) score. Safety and efficacy data were assessed throughout the study.

Results

A total of 486 patients were recruited and treated (1439.9 patient-years of exposure). 308 patients completed the study. Median (range) duration of treatment in this extension study was 1185 (5–2016) days. 476 patients (97.9 %) experienced adverse events; the majority of which (97.8 %) were of mild or moderate severity. The two most common treatment-emergent adverse events were nasopharyngitis (n = 293, 60.3 %) and herpes zoster (n = 94, 19.3 %). For all tofacitinib-treated patients, the incidence rate (patients with events per 100 patient-years) was 10.7 for serious adverse events, 3.3 for serious infections, 7.4 for herpes zoster (serious and non-serious) and 1.2 for malignancies (excluding non-melanoma skin cancer). Mean changes from baseline (start of the index study) in laboratory parameters were consistent with those seen in previously reported studies of tofacitinib. ACR20/50/70 response rates, DAS-defined remission rates and HAQ-DI scores were sustained through to study completion.

Conclusions

Tofacitinib (with or without background methotrexate) demonstrated a stable safety profile and sustained efficacy in Japanese patients with active rheumatoid arthritis. The risk of herpes zoster appears to be higher in Japanese patients treated with tofacitinib than in the global population.

Trial registration

Clinicaltrials.gov NCT00661661. Registered 7 February 2008.

Electronic supplementary material

The online version of this article (doi:10.1186/s13075-016-0932-2) contains supplementary material, which is available to authorized users.

Outcome comparison of ABO-incompatible kidney transplantation with low-dose rituximab and ABO-compatible kidney transplantation: a single-center experience

BACKGROUND

The development of immunosuppressive techniques has helped overcome the ABO incompatibility barrier. However, the outcomes of ABO-incompatible (ABOi) kidney transplantation remain a controversial issue with the advent of the anti-CD20 chimeric antibody rituximab. Herein, we report the outcomes of ABOi kidney transplantation with low-dose rituximab.

PATIENTS AND METHODS

Between June 2006 and April 2013, 42 patients underwent living-related kidney transplantation at our hospital. The patients were divided into 2 groups: ABO-compatible (ABOc; n = 29) and ABOi kidney transplants using low-dose rituximab (100 mg/m(2)) without splenectomy (n = 13). The basic immunosuppression regimen (calcineurin inhibitor [CNI], mycophenolate mofetil [MMF], and steroids) was the same for both groups, except for the use of rituximab and therapeutic apheresis in the ABOi group. We compared post-transplantation renal function, incidents of virus infection, episodes of rejection, and graft survival between the 2 groups.

RESULTS

In our hospital, 30% of recipients received ABOi kidney transplants. The estimated glomerular filtration rate (eGFR) did not differ between the groups. Rejection episodes confirmed by biopsy in the ABOc and ABOi groups were 8 (28%) and 4 (31%) patients (P = .833), acute antibody-mediated rejection was observed in 1 (3.5%) and 2 (15%) patients (P = .165), and virus infection was observed in 14 (48%) and 3 (23%) patients (P = .252), respectively. The 5-year patient survival rate was 100% in both groups, and the 5-year graft survival rates were 95% for ABOc and 100% for ABOi transplants (P = .527).

CONCLUSIONS

These results suggest that the outcomes of ABOi kidney transplantation with low-dose rituximab are similar to those of ABOc kidney transplantation. Further study is necessary to address the efficacy and safety of ABOi kidney transplantation.

Pharmacokinetics, efficacy and safety profiles of etanercept monotherapy in Japanese patients with rheumatoid arthritis: review of seven clinical trials

Conventional synthetic disease-modifying anti-rheumatic drugs, including methotrexate, may not be tolerated by all patients with rheumatoid arthritis (RA), and limited international data for etanercept (ETN) monotherapy are available. The aim of this review was to summarize the clinical program for ETN monotherapy in Japanese patients with RA, which has included a pharmacokinetic study, clinical trials for registration, long-term studies, and once-weekly dosing studies. Pharmacokinetic results showed that serum concentrations of ETN were linear with dose levels and were similar to other international studies. Across interventional studies, 652 Japanese patients with active RA were treated with ETN. In the registration studies, ETN treatment led to consistent improvement in American College of Rheumatology 20/50/70 scores, European League Against Rheumatism Good Response, Disease Activity Score 28 erythrocyte sedimentation rate remission, and Health Assessment Questionnaire disability index. In the long-term studies, efficacy was maintained for up to 180 weeks. Similar results were seen in the once-weekly studies. Across the studies, more than 870 patient-years of exposure to ETN were recorded. Discontinuations owing to lack of efficacy or adverse events were modest and no new safety signals were recorded. These studies demonstrated that ETN monotherapy is efficacious and well-tolerated in Japanese patients with RA.

Pulmonary arterial hypertension associated with connective tissue disease: meta-analysis of clinical trials

OBJECTIVES

Few studies have focused on pulmonary arterial hypertension (PAH) associated with connective tissue diseases (CTDs). The optimal treatment for CTD-PAH has yet to be established.

DESIGN

Meta-analysis of the data from evaluations of treatment for PAH generally (19 studies) and CTD-PAH specifically (nine studies) to compare the effects of pulmonary vasodilative PAH agents. MEDLINE, EMBASE and BIOSIS were searched. English-language full-text articles published between January 1990 and August 2012 were eligible.

SETTING

International.

PARTICIPANTS

Patients with PAH generally (n=3073) and CTD-PAH specifically (n=678).

PRIMARY OUTCOME MEASURE

Exercise capacity (6 min walk distance, 6 MWD).

RESULTS

Patients with PAH (all forms) had mean age 32-55 years (women, 61-87%); CTD-PAH patients had mean age 45-55 years (women, 74-95%). Overall estimate of mean change in 6 MWD from baseline (95% CI) for the active treatment group versus the control group in all patients with PAH was 34.6 m (27.4-41.9 m). Pooled mean differences from the results for patients receiving placebo by subgroup of patients receiving phosphodiesterase (PDE)-5 inhibitors, endothelin receptor antagonists (ERAs) and prostacyclin (PGI2) analogues were 22.4-45.5, 39.5-44.2 and 12.4-64.9 m, respectively. Overall estimate of mean difference between changes in 6 MWD in patients with CTD-PAH was 34.2 m (23.3-45.0 m). Pooled mean differences by subgroup of patients receiving PDE-5 inhibitors, ERAs and PGI2 analogues in patients with CTD-PAH were 37.0-47.1, 14.1-21.7 and 21.0-108.0 m, respectively. ERAs were less effective in patients with CTD-PAH than all-form patients with PAH: 14.1 m (-4.4-32.6 m) vs 39.5 m (19.5-59.6 m) for bosentan and 21.7 m (2.2-41.3 m) vs 44.2 m (30.2-58.2 m) for ambrisentan.

CONCLUSIONS

All three types of PAH agent are effective. However, ERAs may be a less effective choice against CTD-PAH; further studies are needed. Limitations include the limited number of studies for some agents and for patients with CTD-PAH.

CTLA-4Ig immunotherapy of obesity-induced insulin resistance by manipulation of macrophage polarization in adipose tissues

It has been established that obesity alters the metabolic and endocrine function of adipose tissue and, together with accumulation of adipose tissue macrophages, contributes to insulin resistance. Although numerous studies have reported that shifting the polarization of macrophages from M1 to M2 can alleviate adipose tissue inflammation, manipulation of macrophage polarization has not been considered as a specific therapy. Here, we determined whether cytotoxic T-lymphocyte-associated antigen-4IgG1 (CTLA-4Ig) can ameliorate insulin resistance by induction of macrophages from proinflammatory M1 to anti-inflammatory M2 polarization in the adipose tissues of high fat diet-induced insulin-resistant mice. CTLA4-Ig treatment prevented insulin resistance by changing gene expression to M2 polarization, which increased the levels of arginase 1. Furthermore, flow cytometric analysis confirmed the alteration of polarization from CD11c (M1)- to CD206 (M2)-positive cells. Concomitantly, CTLA-4Ig treatment resulted in weight reductions of epididymal and subcutaneous adipose tissues, which may be closely related to overexpression of apoptosis inhibitors in macrophages. Moreover, proinflammatory cytokine and chemokine levels decreased significantly. In contrast, CCAAT enhancer binding protein α, peroxisome proliferator-activated receptor γ, and adiponectin expression increased significantly in subcutaneous adipose tissue. This novel mechanism of CTLA-4lg immunotherapy may lead to an ideal anti-obesity/inflammation/insulin resistance agent.

Involvement of estrogen receptor β in maintenance of serotonergic neurons of the dorsal raphe

The serotonergic neurons of the dorsal raphe (DR) nucleus in the CNS are involved in fear, anxiety and depression. Depression and anxiety occur quite frequently in postmenopausal women, but estrogen replacement to correct these CNS disorders is at present not favored because estrogen carries with it an increased risk for breast cancer. Serotonin synthesis, release and reuptake in the DR are targets of pharmaceuticals in the treatment of depression. In the present study we have examined by immunohistochemistry, the expression of two nuclear receptors, that is, the estrogen receptors ERα and ERβ. We found that ERβ but not ERα is strongly expressed in the DR and there is no sex difference and no change with ageing in the number of tryptophan hydroxylase (TPH)-positive neurons in the DR of wild-type (WT) mice. However, in ovariectomized (OVX) WT and in ERβ(-/-) mice, there was a marked reduction in the number of TPH-positive normal-looking neurons and a marked increase in TPH-positive spindle-shaped cells. These neuronal changes were prevented in mice 1-3 weeks (but not 10 weeks) after OVX by the selective ERβ agonist, LY3201, given as continuous release pellets for 3 days. The ERβ agonist had no effects on glucose homeostasis. Thus, the onset of action of the ERβ agonist is rapid but there is a limited window in time after estrogen loss when the drug is useful. We conclude that, rather than estradiol, ERβ agonists could be useful pharmaceuticals in maintaining functional DR neurons to treat postmenopausal depression.

Factors affecting assessment of severity of aggressive incidents: using the Staff Observation Aggression Scale - Revised (SOAS-R) in Japan

The aim of this study is to investigate factors associated with overall judgements of aggression severity as provided by ward nurses, using the Japanese-language version of the Staff Observation Aggression Scale - Revised (SOAS-R). Nurses who observed 326 aggressive incidents involving psychiatric inpatients at five mental health facilities in Japan provided their assessments of the incident severity both on the established rating scale, the SOAS-R, and on a visual analogue scale (VAS), a one-item scale to indicate overall aggression severity. To evaluate the factors influencing the VAS severity scores, a multiple regression analysis was performed, in which consumer, nurse and ward characteristics were added consecutively, along with SOAS-R severity scores as independent variables. SOAS-R scores explained 17.6% of the VAS severity scores. Independently from the SOAS-R scores, the gender and age of the aggressive consumers (adjusted R(2) = 10.0%), as well as the gender of the nurses who reported the aggression (adjusted R(2) = 4.1%), each explained VAS severity score to a significant degree. Apart from the SOAS-R scores, consumer and nurse characteristics appeared to influence the overall judgements of severity of aggressive incidents, which may be connected to decisions about the use of coercive measures, such as seclusion/restraint or forced medication.

T cell-specific overexpression of interleukin-27 receptor α subunit (WSX-1) prevents spontaneous skin inflammation in MRL/lpr mice

BACKGROUND

Interleukin (IL)-27 and WSX-1, the receptor α-specific subunit, have been shown to play important roles in initiating Th1 responses and in inducing immune modulation, and the immunosuppressive effect of IL-27 appears to be exerted via suppression of IL-10 and IL-17, which may participate in the pathogenesis of human systemic lupus erythematosus (SLE).

OBJECTIVES

To examine the significance of IL-27/WSX-1 signalling in spontaneous skin inflammation of MRL/lpr mice, a model for SLE.

METHODS

The severity and development of skin lesions, dermal inflammatory cells and epidermal-dermal depositions in the skin lesions of MRL/lpr mice with CD2-promoted WSX-1 overexpression (WSX-1 Tg mice) and those with globally disrupted WSX-1 (WSX-1 KO mice) were examined and compared with those of MRL/lpr mice.

RESULTS

By 4 months of age, both WSX-1 KO mice and control MRL/lpr mice developed predominantly similar skin inflammation, while WSX-1 Tg mice hardly did so, demonstrating that intensifying IL-27/WSX-1 signalling on T cells prevents the spontaneous skin inflammation. WSX-1 KO mice showed Th2-type skin inflammation as evidenced by the Th2-prone dermal infiltrating cells and an absence of cutaneous Th1-type IgG deposition. Interestingly, there were significant IL-17+ dermal infiltrating cells in both WSX-1 KO and control MRL/lpr mice, which might potentially contribute to the formation of skin inflammation in these mice.

CONCLUSIONS

These data indicate that IL-27/WSX-1 signalling may play a protective role in the development of SLE-like skin inflammation, and modulating IL-27/WSX-1 signalling might be an interesting therapeutic strategy in the treatment of SLE.

Spatiotemporal dynamics of the expression of estrogen receptors in the postnatal mouse brain

This study reports on the spatiotemporal dynamics of the expression of estrogen receptors (ERs) in the mouse central nervous system (CNS) during the early postnatal and the peripubertal period. At postnatal day 7 (P7), neurons with strong nuclear immunostaining for both ERalpha and ERbeta1 were widely distributed throughout the brain. Sucrose density gradient sedimentation followed by western blotting supported the histochemical evidence for high levels of both ERs at P7. Over the following 2 days, there was a rapid downregulation of ERs. At P9, ERalpha expression was visible only in the hypothalamic area. Decline in ERbeta1 expression was slower than that of ERalpha, and ERalpha-negative, ERbeta1-positive cells were observed in the dentate gyrus and walls of third ventricle. Between P14 and P35, ERs were undetectable except for the hypothalamic area. As before P7, the ovary does not produce estrogen but does produce 5alpha-androstane-3beta, 17beta-diol (3betaAdiol), an estrogenic metabolite of dihydrotestosterone, we examined the effects of high levels of 3betaAdiol in the postnatal period. We used CYP7B1 knockout mice which cannot hydroxylate and inactivate 3betaAdiol. The brains of these mice are abnormally large with reduced apoptosis. In the early postnatal period, there was 1-week delay in the timing of the reduction in ER expression in the brain. These data reveal that the time when ERs might be activated in the brain is limited to the first 8 postnatal days. In addition, the importance of aromatase has to be reconsidered as the alternative estrogen, 3betaAdiol, is important in neuronal function in the postnatal brain.

DU-176b, a potent and orally active factor Xa inhibitor: in vitro and in vivo pharmacological profiles

BACKGROUND

Factor Xa (FXa), a key serine protease that converts prothrombin to thrombin in the coagulation cascade, is a promising target enzyme for the prophylaxis and treatment of thromboembolic diseases. DU-176b is a novel antithrombotic agent that directly inhibits FXa activity.

OBJECTIVE

To evaluate the in vitro pharmacological profiles and in vivo effects of DU-176b in animal models of thrombosis and bleeding.

METHODS

In vitro, FXa inhibition, specificity and anticoagulant activities were examined. Oral absorption was studied in rats and cynomolgus monkeys. In vivo effects were studied in rat and rabbit models of venous thrombosis and tail bleeding.

RESULTS

DU-176b inhibited FXa with Ki values of 0.561 nm for free FXa, 2.98 nm for prothrombinase, and exhibited >10 000-fold selectivity for FXa. In human plasma, DU-176b doubled prothrombin time and activated partial thromboplastin time at concentrations of 0.256 and 0.508 microm, respectively. DU-176b did not impair platelet aggregation by ADP, collagen or U46619. DU-176b was highly absorbed in rats and monkeys, as demonstrated by more potent anti-Xa activity and higher drug concentration in plasma following oral administration than a prototype FXa inhibitor, DX-9065a. In vivo, DU-176b dose-dependently inhibited thrombus formation in rat and rabbit thrombosis models, although bleeding time in rats was not significantly prolonged at an antithrombotic dose.

CONCLUSIONS

DU-176b is a more potent and selective FXa inhibitor with high oral bioavailability compared with its prototype, DX-9065a. DU-176b represents a promising new anticoagulant for the prophylaxis and treatment of thromboembolic diseases.

Monosomy and trisomy of 15q24-qter with cleft lip and palate

Chromosome 15 aberrations clinically present as facial dysmorphisms such as a prominent nose, low-set ears, micrognathia and a short neck; a cleft lip and palate have not been reported. This is the first reported case of de-novo terminal deletion at 15q24 with a cleft lip and palate and low-set ears. The baby boy had a complete cleft lip and palate on the left side and incomplete cleft lip and palate on the right. A chromosomal study revealed partial monosomy and trisomy of the long arm of chromosome 15, with a karyotype of 46,XY,add(15)(24q) de novo. Surgery for lip plasty was performed at 6 months old and for palate plasty at 1 year and 9 months. Both operations were uneventful, although preoperative and postoperative examinations showed high creatinine phosphokinase values. At 3 years old, mild mental retardation was observed, but his physical development was normal.

Amelioration of human lupus-like phenotypes in MRL/lpr mice by overexpression of interleukin 27 receptor alpha (WSX-1)

Objective:

In the present work, we investigate the role of interleukin (IL)27/IL27 receptor α (Rα) (WSX-1) in the development of autoimmune disorders in the MRL/lpr mouse, which is considered as an experimental model of systemic lupus erythaematosus (SLE) in humans.

Methods:

We generated two strains of WSX-1 transgenic mice in the MRL/lpr background with different expression levels of WSX-1, and investigated the effect of WSX-1 overexpression on survival, glomerulonephritis and immunological properties.

Results:

In comparison with wild type (WT) MRL/lpr and transgenic (Tg) low (TgL) mice, Tg high (TgH) mice exhibited a prolonged lifespan and no apparent development of autoimmune nephritis. Production of anti-dsDNA antibody and total IgG and IgG2a were significantly lower in TgH mice than those of TgL and WT mice. The expressed amounts of interferon (IFN)γ and IL4 mRNA by CD4⁺ T cells from Tg mice decreased in a dose-dependent fashion. CD4⁺ splenic lymphocytes in TgH mice were more subject to the IL27-mediated suppression of cytokine production. In vitro stimulation of CD4⁺ T cells by IL27 resulted in over phosphorylation of STAT3 in TgH cells than in WT cells.

Conclusion:

WSX-1 overexpression in the MRL/lpr background rendered the autoimmune prone mice protected from the development of autoimmune diseases. Our results suggest that IL27 signalling may be a therapeutic target against autoimmune diseases, including human SLE.

Complete nucleotide sequence of a Japanese isolate of Chrysanthemum virus B (genus Carlavirus)

The complete nucleotide sequence of a Chrysanthemum virus B isolate from Japan (CVB-S) has been determined. The genomic RNA of CVB-S is 8,990 nucleotides long, excluding the poly(A) tail and, like that of other carlaviruses, contains six open reading frames (ORFs). Multiple alignment and phylogenetic analyses indicated that the phylogenetic relationship among members of the genus Carlavirus is very diverse, with phlox virus S being the closest relative of CVB. In aphid transmission tests, CVB-S was transmitted at a very low rate by Aphis gossypii, a new vector of the virus.

Protection against autoimmune nephritis in MyD88-deficient MRL/lpr mice

OBJECTIVE

To determine whether innate receptor signals play an important role in the development of autoimmune nephritis in MRL/lpr mice, an experimental model of lupus nephritis.

METHODS

MyD88 is a critical adaptor that is involved in signaling pathways through all of the Toll-like receptors (TLRs) except TLR-3. We therefore generated MyD88-knockout (MyD88-KO) MRL/lpr mice and examined them for histopathologic changes in the kidneys, cumulative survival rates, extent of lymphadenopathy and splenomegaly, serum chemistry, and immunologic parameters. In addition, to define the role of the MyD88-independent pathway in autoimmune nephritis, we injected MyD88-KO MRL/lpr mice intraperitoneally with either poly(I-C) (50 or 100 microg per mouse) or phosphate buffered saline and examined them for survival as well as for histopathologic, serologic, and immunologic parameters.

RESULTS

In comparison with wild-type mice, MyD88-KO MRL/lpr mice exhibited a prolonged lifespan, with no apparent development of autoimmune nephritis. Their kidneys showed no glomerular cell proliferation or crescent formation, along with a drastic decrease in the mesangial matrix. Lymphadenopathy and splenomegaly were less pronounced. Serum titers of anti-double-stranded DNA (anti-dsDNA) and production of cytokines, including interferon-alpha (IFNalpha), interleukin-12 (IL-12), IL-6, and IFNgamma, in splenocytes were significantly reduced in MyD88-KO MRL/lpr mice. Interestingly, MyD88-KO MRL/lpr mice that had been treated with the MyD88-independent TLR-3 ligand poly(I-C) showed an almost complete reversion to the features of wild-type mice, demonstrating crescentic glomerulonephritis, with significant elevation of serum anti-dsDNA titers and increased cytokine production in splenocytes.

CONCLUSION

The findings indicate that both MyD88-dependent and MyD88-independent innate signals play a crucial role in the development of autoimmune nephritis in MRL/lpr mice.

Membranous glomerulonephritis development with Th2-type immune deviations in MRL/lpr mice deficient for IL-27 receptor (WSX-1)

MRL/lpr mice develop spontaneous glomerulonephritis that is essentially identical with diffuse proliferative glomerulonephritis (World Health Organization class IV) in human lupus nephritis. Lupus nephritis is one of the most serious complications of systemic lupus erythematosus. Diffuse proliferative glomerulonephritis is associated with autoimmune responses dominated by Th1 cells producing high levels of IFN-gamma. The initial mounting of Th1 responses depends on the function of the WSX-1 gene, which encodes a subunit of the IL-27R with homology to IL-12R. In mice deficient for the WSX-1 gene, proper Th1 differentiation was impaired and abnormal Th2 skewing was observed during infection with some intracellular pathogens. Disruption of the WSX-1 gene dramatically changed the pathophysiology of glomerulonephritis developing in MRL/lpr mice. WSX-1-/- MRL/lpr mice developed disease resembling human membranous glomerulonephritis (World Health Organization class V) with a predominance of IgG1 in glomerular deposits, accompanied by increased IgG1 and IgE in the sera. T cells in WSX-1-/- MRL/lpr mice displayed significantly reduced IFN-gamma production along with elevated IL-4 expression. Loss of WSX-1 thus favors Th2-type autoimmune responses, suggesting that the Th1/Th2 balance may be a pivotal determinant of human lupus nephritis development.

Amelioration of autoimmune nephritis by imatinib in MRL/lpr mice

OBJECTIVE

To examine whether the platelet-derived growth factor (PDGF) receptor antagonist imatinib ameliorates glomerulonephritis in MRL/lpr mice, a condition that is similar to severe lupus nephritis in humans.

METHODS

Sixteen-week-old MRL/lpr female mice having an advanced stage of glomerulonephritis were divided into 3 groups according to treatment: 1) 50 mg/kg or 2) 10 mg/kg of imatinib (administered orally 4 times a week up to 24 weeks of age) or 3) vehicle solution (untreated group). The histopathologic condition of the kidneys and salivary glands of each mouse as well as the cumulative survival rates, extent of lymphadenopathy and splenomegaly, and serum chemistry and immunologic values were assessed.

RESULTS

In mice treated with 50 mg/kg imatinib, neither proliferation of glomerular cells nor crescent formation occurred. A drastic decrease in mesangial matrix was noted. Mice treated with 50 mg/kg imatinib had a prolonged life span compared with mice treated with 10 mg/kg imatinib and untreated mice. Expression of PDGF receptor and transforming growth factor beta messenger RNA in the kidneys was significantly reduced in the 50 mg/kg imatinib-treated mice compared with that in the 10 mg/kg imatinib-treated mice (P < 0.05) and the untreated mice (P < 0.01). Intriguingly, lymphadenopathy and salivary gland inflammation were also attenuated in imatinib-treated mice, in a dose-dependent manner. Serum levels of IgG and anti-double-stranded DNA antibodies were also reduced in the imatinib-treated mice.

CONCLUSION

These findings indicate that imatinib has a pleiotropic therapeutic effect, namely, the inhibition of PDGF signaling and immunosuppression, on the glomerulonephritis of MRL/lpr mice, which suggests a potential application of this drug in the treatment of human lupus nephritis.