To switch or not to switch: results of a nationwide guideline of mandatory switching from originator to biosimilar etanercept. One-year treatment outcomes in 2061 patients with inflammatory arthritis from the DANBIO registry.

OBJECTIVES: Real-world evidence on effectiveness of switching to biosimila r etanercept is scarce. In Denmark, a nationwide guideline of mandatory switch from 50 mg originator (ETA) to biosimilar (SB4) etanercept was issued for patients with rheumatoid arthritis (RA), psoriatic arthritis (PsA) and axial spondyloarthritis (AxSpA) in 2016. Clinical characteristics and treatment outcomes were studied in ETA-treated patients, who switched to SB4 (switchers) or maintained ETA (non-switchers). Retention rates were compared with that of a historic cohort of ETA-treated patients. Switchers who resumed ETA treatment (back-switchers) were characterised. METHODS: Observational cohort study based on the DANBIO registry. Treatment retention was explored by Kaplan-Meier plots and Cox regression (crude, adjusted). RESULTS: 1621 (79%) of 2061 ETA-treated patients switched to SB4. Disease activity was unchanged 3 months' preswitch/postswitch. Non-switchers often received 25 mg ETA (ETA 25 mg pens/syringes and powder solution were still available). One-year adjusted retention rates were: non-switchers: 77% (95% CI: 72% to 82%)/switchers: 83% (79% to 87%)/historic cohort: 90% (88% to 92%). Patients not in remission had lower retention rates than patients in remission, both in switchers (crude HR 1.7 (1.3 to 2.2)) and non-switchers (2.4 (1.7 to 3.6)). During follow-up, 120 patients (7% of switchers) back-switched to ETA. Back-switchers' clinical characteristics were similar to switchers, and reasons for SB4 withdrawal were mainly subjective. CONCLUSION: Seventy-nine per cent of patients switched from ETA to SB4. After 1 year, adjusted treatment retention rates were lower in switchers versus the historic ETA cohort, but higher than in non-switchers. Withdrawal was more common in patients not in remission. The results suggest that switch outcomes in routine care are affected by patient-related factors and non-specific drug effects.

Validity and completeness of rheumatoid arthritis diagnoses in the nationwide DANBIO clinical register and the Danish National Patient Registry.

OBJECTIVES: In Denmark, patients with rheumatoid arthritis (RA) are registered in the nationwide clinical DANBIO quality register and the Danish National Patient Registry (DNPR). The aim was to study the validity of the RA diagnosis and to estimate the completeness of relevant RA cases in each registry. STUDY DESIGN AND SETTING: Patients registered for the first time in 2011 with a diagnosis of RA were identified in DANBIO and DNPR in January 2013. For DNPR, filters were applied to reduce false-positive cases. The diagnosis was verified by a review of patient records. We calculated the positive predictive values (PPVs) of the RA diagnosis registrations in DANBIO and DNPR, and estimated the registry completeness of relevant RA cases for both DANBIO and DNPR. Updated data from 2011 to 2015 from DANBIO were retrieved to identify patients with delayed registration, and the registry completeness and PPV was recalculated. RESULTS: We identified 1,678 unique patients in DANBIO or in DNPR. The PPV (2013 dataset) was 92% in DANBIO and 79% in DNPR. PPV for DANBIO on the 2015 update was 96%. The registry completeness of relevant RA cases was 43% in DANBIO, increasing to 91% in the 2015 update and 90% in DNPR. CONCLUSION: DANBIO held a high proportion of true RA cases (96%) and was found to be superior to the DNPR (79%) with regard to the validity of the diagnosis. Both registries were estimated to have a high completeness of RA cases treated in hospital care (~90%).

A nationwide non-medical switch from originator infliximab to biosimilar CT-P13 in 802 patients with inflammatory arthritis: 1-year clinical outcomes from the DANBIO registry.

OBJECTIVES: According to guidelines, a nationwide non-medical switch from originator (INX, Remicade) to biosimilar infliximab (Remsima, CT-P13) was conducted in Danish patients with rheumatoid arthritis (RA), psoriatic arthritis (PsA) and axial spondyloarthritis (AxSpA). We investigated disease activity before/after switching and retention rates in the DANBIO registry. METHODS: Disease activities 3 months before and after switch and changes over time were calculated. Flare was defined as change in 28 Joint Disease Activity Score (∆DAS28) ≥1.2 (RA/PsA) or Ankylosing Spondylitis Disease Activity Score (∆ASDAS) ≥1.3 (AxSpA). Crude and adjusted retention rates were compared with a historic cohort of INX-treated patients. RESULTS: Eight hundred and two patients switched (403 RA/120 PsA/279 AxSpA; 51% women, age (median (IQR): 55 (44-66)) years). Follow-up was 413 (339-442) days. Prior INX treatment duration was 6.8 (4.3-9.5) years. Disease activities were similar 3 months before/after switch. Crude 1-year CT-P13 retention rate (84.1 (95% CI 81.3 to 86.5)) was similar to the historic IFX cohort (86.2 (95% CI 84.0 to 88.0), p=0.22). The adjusted absolute retention rates were 83.4 (95% CI 80.8 to 86.2) and 86.8% (95% CI 84.8 to 88.8), respectively (p=0.03). In total 132 patients withdrew (lack of effect: 71/132=54%, adverse events: 37/132=28%). Patients with previous INX treatment duration >5 years had longer CT-P13 retention. CONCLUSION: In 802 arthritis patients treated with INX for median >6 years, a nationwide non-medical switch to CT-P13 had no negative impact on disease activity. Adjusted 1-year CT-P13 retention rate was slightly lower than for INX in a historic cohort.

Ankylosing Spondylitis versus Nonradiographic Axial Spondyloarthritis: Comparison of Tumor Necrosis Factor Inhibitor Effectiveness and Effect of HLA-B27 Status. An Observational Cohort Study from the Nationwide DANBIO Registry.

OBJECTIVE: To compare baseline disease activity and treatment effectiveness in biologic-naive patients with nonradiographic axial spondyloarthritis (nr-axSpA) and ankylosing spondylitis (AS) who initiate tumor necrosis factor inhibitor (TNFi) treatment and to study the role of potential confounders (e.g., HLA-B27 status). METHODS: Observational cohort study based on prospectively registered data in the nationwide DANBIO registry. We used Kaplan-Meier plots, Cox, and logistic regression analyses to study the effect of diagnosis (nr-axSpA vs AS) and potential confounders (sex/age/start yr/HLA-B27/disease duration/TNFi-type/smoking/baseline disease activity) on TNFi adherence and response [e.g., Bath Ankylosing Spondylitis Activity Index (BASDAI) 50%/20 mm]. RESULTS: The study included 1250 TNFi-naive patients with axSpA (29% nr-axSpA, 50% AS, 21% lacked radiographs of sacroiliac joints). Patients with nr-axSpA were more frequently women (50%/27%) and HLA-B27-negative (85/338 = 25%), compared to AS (81/476 = 17%; p < 0.01). At TNFi start patients with nr-axSpA had higher visual analog scale scores [median (quartiles)] for pain: 72 mm (55-84)/65 mm (48-77); global: 76 mm (62-88)/68 mm (50-80); fatigue: 74 mm (55-85)/67 mm (50-80); and BASDAI: 64 (54-77)/59 (46-71); all p < 0.01. However, patients with nr-axSpA had lower C-reactive protein: 7 mg/l (3-17)/11 mg/l (5-22); and BAS Metrology Index: 20 (10-40)/40 (20-50); all p < 0.01. Median (95% CI) treatment adherence was poorer in nr-axSpA than in AS: 1.59 years (1.15-2.02) versus 3.67 years (2.86-4.49), p < 0.0001; but only in univariate and not confounder-adjusted analyses (p > 0.05). Response rates were similar in AS and nr-axSpA (p > 0.05). HLA-B27 negativity was associated with poorer treatment adherence [HLA-B27 negative/positive, nr-axSpA: HR 1.74 (1.29-2.36), AS: HR 2.04 (1.53-2.71), both p < 0.0001]; and lower response rates (nr-axSpA: 18/61 = 30% vs 93/168 = 55%; AS: 17/59 = 29% vs 157/291 = 54%, both p < 0.05). CONCLUSION: In this nationwide cohort, patients with nr-axSpA had higher subjective disease activity at start of first TNFi treatment, but similar outcomes to patients with AS after confounder adjustment. HLA-B27 positivity was associated with better outcomes irrespective of axSpA subdiagnosis.

Impact of tobacco smoking on response to tumour necrosis factor-alpha inhibitor treatment in patients with ankylosing spondylitis: results from the Danish nationwide DANBIO registry.

OBJECTIVES: To investigate the association between tobacco smoking and disease activity, treatment adherence and treatment responses in patients with AS treated with their first tumour necrosis factor-alpha inhibitor (TNFi) therapy in routine care. METHODS: Observational cohort study based on the Danish nationwide DANBIO registry. Kaplan-Meier plots, Cox and logistic regression analyses by smoking status (current/never/previous) were calculated for treatment adherence and BASDAI 50%/20 mm-response. Additional stratified analyses were performed for gender and TNFi-type. RESULTS: Of 1576 AS patients included in the study, 1425(90%) had known smoking status (current/never/previous: 43%/41%/16%). The median follow-up time was 2.02 years (IQR 0.69-5.01). At baseline, current smokers compared with never smokers had longer disease duration (4 years (1-12)/2 years (0-10)), higher BASDAI (61 mm (47-73)/58 mm (44-70)), BASFI (53 mm (35-69)/46 mm (31-66)) and BASMI (40 mm (20-60)/30 mm (10-50)) scores (all P < 0.01). Current and previous smokers had shorter treatment adherence than never smokers (current: 2.30 years (1.81-2.79) (median (95% CI)); previous: 2.48 years (1.56-3.40), never: 4.12 years (3.29-4.95)), P < 0.0001). Similar results were found in multivariate analyses (current versus never smokers, HR 1.41 (95% CI 1.21-1.65), P < 0.001), most pronounced among men. Current smokers had poorer 6 months' BASDAI50%/20 mm-response rate than never smokers (42%/58%, P < 0.001). In multivariate analyses, current smokers had lower odds of achieving BASDAI50%/20 mm-response than never smokers, both overall (OR 0.48 (95% CI 0.35-0.65), P < 0.0001) and for the different TNFi-types (adalimumab 0.45 (0.27-0.76)/etanercept 0.24 (0.10-0.61)/infliximab 0.57 (0.34-0.95)). CONCLUSION: In this study of TNFi-treated AS patients in clinical practice, current and previous smokers had significantly poorer patient-reported outcomes at baseline, shorter treatment adherence and poorer treatment response compared with never smokers.

[Schnitzler syndrome is a diagnostic challenge]. / Schnitzlers syndrom er en diagnostisk udfordring.

Schnitzler syndrome (SS) is a rare autoinflammatory disorder characterized by a chronic urticarial rash and a monoclonal immunoglobulin M gammopathy, accompanied by recurrent fever, lymphadenopathy, arthralgia or arthritis, hepato- or splenomegaly and elevated levels of markers of systemic inflammation. Because patients often present to various specialists with different symptoms the syndrome is often undiagnosed, and it can take years before the correct diagnosis is made. Treatment with interleukin-1 receptor antagonists has a rapid effect on SS.

Discordance of Global Assessments by Patient and Physician Is Higher in Female than in Male Patients Regardless of the Physician's Sex: Data on Patients with Rheumatoid Arthritis, Axial Spondyloarthritis, and Psoriatic Arthritis from the DANBIO Registry.

OBJECTIVE: To assess the frequency of discordance in patient's (PtGA) and physician's (PGA) global assessment, and to investigate whether higher discordance in female patients compared with male patients is associated with the physician's sex in patients with rheumatoid arthritis (RA), axial spondyloarthritis (axSpA), and psoriatic arthritis (PsA). METHODS: PtGA, PGA, and other patient-related variables were retrieved from the Danish DANBIO registry, used nationwide to monitor patients with RA, axSpA, and PsA. A questionnaire was sent to all physicians registering in DANBIO (n = 265) regarding individual physician characteristics including sex and age. Discordance was defined as PtGA > 20 mm higher (or lower) than PGA. First encounters between patients and physicians were analyzed using descriptive statistics and mixed model regression analysis. RESULTS: Ninety physicians (34%) returned the questionnaire and were pairwise matched with 10,282 first patient encounters (8300 patients with RA, 524 axSpA, and 1458 PsA). The frequency of discordant (PtGA > PGA) encounters (not including PGA > PtGA seen in < 2%) in RA, axSpA, and PsA was 49.0%, 48.3%, and 56.5%, respectively. Discordance was more common in female patients with high scores on functional disability, pain, and fatigue across the 3 diseases, whereas it was independent of the physician's sex. CONCLUSION: In this study on Danish patients with RA, axSpA, and PsA, the PtGA was > 20 mm higher than the PGA in about half of the encounters, and more common in female patients of both female and male physicians. This finding highlights one of the challenges in shared decision making.

Impact of different infliximab dose regimens on treatment response and drug survival in 462 patients with psoriatic arthritis: results from the nationwide registries DANBIO and ICEBIO.

OBJECTIVE: The aim of this study was to describe dose regimens, dose escalation and clinical outcomes in TNF-α inhibitor (TNFi)-naive patients with PsA treated with infliximab in routine rheumatology care. METHODS: We conducted an observational cohort study based on the nationwide Danish Rheumatologic Database (DANBIO) and Center for Rheumatology Research (ICEBIO) registries. Stratified by country, characteristics of patients treated with ≤3 mg infliximab/kg body weight, 3-5 mg/kg or ≥5 mg/kg every 8 weeks were described. Outcomes were evaluated by ACR 20%, 50% and 70% (ACR20/50/70) responses and European League Against Rheumatism good response after 6 months, disease activity after 12 months, Kaplan-Meier plots and regression analyses. RESULTS: Four hundred and sixty-two patients (376 Danish, 86 Icelandic) received treatment with infliximab. In Danish patients, the starting dose was ≤3 mg/kg in 110 patients (29%), 3-5 mg/kg in 157 (42%), ≥5 mg/kg in 38 (10%) and unregistered in 71 (19%). In Icelandic patients, corresponding numbers were 64 (74%), 17 (27%), 0 (0%) and 5 (6%). Patients with a higher body weight received lower doses per kilogram. Danish patients received higher doses than Icelandic patients at baseline [median 3.1 (interquartile range 3.0-3.8) vs 2.3 (2.1-2.9) mg/kg, P < 0.05] and after 12 months [3.3 (3.0-4.5) vs 2.9 (2.2-3.5) mg/kg, P < 0.0001]. After 12 months, 58% of Danish and 66% of Icelandic patients maintained treatment. Danish patients had shorter drug survival than Icelandic patients (1183 vs 483 days). In univariate analyses stratified by country, time until dose escalation, response rates, drug survival and 1-year's disease activity were independent of starting dose. Drug survival was shorter among patients not receiving concomitant MTX. CONCLUSION: In clinical practice, > 70% of Icelandic and Danish PsA patients treated with infliximab received sustained doses below the 5 mg/kg every 8 weeks recommended in international guidelines. Lower starting doses did not affect drug survival or response.

Clinical response, drug survival, and predictors thereof among 548 patients with psoriatic arthritis who switched tumor necrosis factor α inhibitor therapy: results from the Danish Nationwide DANBIO Registry.

OBJECTIVE: To describe the frequency of treatment switching and outcomes among patients with psoriatic arthritis (PsA) who switched tumor necrosis factor α inhibitor (TNFi) agents in routine care. METHODS: We conducted an observational cohort study based on the Danish nationwide DANBIO registry. Treatment outcomes were evaluated using the American College of Rheumatology criteria for 20% improvement (ACR20)/ACR50/ACR70, European League Against Rheumatism (EULAR) response criteria for good response, and the 28-joint count Disease Activity Score (DAS28) (remission). Kaplan-Meier and regression analyses were used for drug survival analyses and to identify predictors of outcome after treatment switching. RESULTS: Of 1,422 patients starting TNFi agents, 548 patients (39%) switched to a second biologic drug during up to 10 years of followup. Median followup was 2.3 years (interquartile range [IQR] 1.0-4.3 years). Switchers were more frequently women (56% versus 45%), had a shorter disease duration (3 versus 4 years), a higher median Health Assessment Questionnaire (HAQ) score (1.1 [IQR 0.6-1.6] versus 0.9 [IQR 0.5-1.4]), DAS28 (4.8 [4.0-5.7] versus 4.4 [3.6-5.2]), pain score on a visual analog scale (VAS) (65 mm [46-77] versus 62 mm [40-75]), and fatigue score on a VAS (69 mm [50-83] versus 64 mm [42-80] mm) (all P < 0.05 at start of first TNFi). During the first and second treatment, HAQ, DAS28, and VAS scores and C-reactive protein levels had decreased after 6 months (all P < 0.05), and median drug survival was 2.2 versus 1.3 years (P < 0.001). Lower fatigue score increased survival of the second TNFi. After switching, the proportions of patients achieving a sustained ACR20, ACR50, ACR70, EULAR good response, and DAS28 remission after 3-6 months were 22% (number needed to treat [NNT] 4.5), 13% (NNT 7.9), 5% (NNT 20), 19% (NNT 5.3), and 34% (NNT 2.9), respectively. Response rates were lower during the second treatment (all P < 0.01 versus first TNFi). At the 2-year visit, 47% of switchers had achieved an ACR20 response. No differences between drug-drug combinations were found. CONCLUSION: Thirty-nine percent of the patients with PsA switched TNFi agents. Response rates and drug survival were lower after switching; however, half of the switchers had an ACR20 response 2 years after starting the first TNFi.

Incidences of overall and site specific cancers in TNFα inhibitor treated patients with rheumatoid arthritis and other arthritides - a follow-up study from the DANBIO Registry.

OBJECTIVES: To investigate the incidence of cancer in arthritis patients treated with or without TNFα inhibitors (TNF-I). METHODS: Arthritis patients from the DANBIO database were followed-up for cancer in the Danish Cancer Registry during 2000-2008. RESULTS: Hazard ratio for cancer overall was 1.02 (95% confidence interval (CI) 0.80-1.30) in 3347 TNF-I-treated RA patients compared to non-treated. Excess among TNF-I-treated was found for colon cancer (HR 3.52 (95%CI 1.11-11.15), whereas 6 and 0 ovarian cancer cases were observed in treated and non-treated patients, respectively. Compared to the general population, TNF-I-treated RA patients had increased risk for cancer overall, cancer in lymphatic-haematopoietic tissue and non-melanoma skin cancer, while non-RA patients had no increase in overall cancer risk. CONCLUSIONS: Our results suggest that TNF-I therapy in routine care is not associated with an overall excess of cancer in arthritis patients, but observed increased risks of colon and ovarian cancer need further investigation.

Clinical response, drug survival and predictors thereof in 432 ankylosing spondylitis patients after switching tumour necrosis factor α inhibitor therapy: results from the Danish nationwide DANBIO registry.

OBJECTIVE: To investigate frequencies and reasons for switching, treatment responses and drug survival in patients with ankylosing spondylitis (AS) switching tumour-necrosis-factor-α inhibitor (TNFi) treatment in routine clinical care. METHODS: AS patients were identified in the Danish nationwide DANBIO registry. Disease activity, treatment responses (50% or 20 mm reduction in Bath AS Disease Activity Index (BASDAI)), duration and rates of drug survival and predictors thereof were studied in patients receiving ≥2 different biological drugs. RESULTS: Of 1436 AS patients starting TNFi treatment, 432 patients (30%) switched to a second and 137 (10%) to a third biological drug. Compared with non-switchers, switchers were more frequently women (33%/22%), had shorter disease duration (3 years/5 years) and higher BASDAI (62(52-76) mm/56(43-69) mm (median(interquartile-range))), Bath AS Functional Index (BASFI) (54(39-71) mm/47(31-65) mm) and visual-analogue-scale (VAS) global, pain and fatigue scores when they started the first TNFi (all p<0.01). Main reason for switching was lack of response (56%). During the first, second and third treatment BAS- and VAS scores had decreased after 6 months' treatment (all p<0.05). Median drug survivals were 3.1, 1.6 and 1.8 years respectively (p<0.001). After 2 years of treatment 52% of switchers and 63% of non-switchers had achieved response (number needed to treat 1.9 and 1.6, respectively, p=0.01). Drug survivals were similar regardless of the reason for switching. Male gender and low BASFI predicted drug survival of the second TNFi. CONCLUSIONS: Nearly one-third of AS patients in clinical practice switched biological treatment. Response rates and drug survivals were lower among switchers, however, half of switchers achieved treatment response.