Proteasome inhibition and mechanism of resistance to a synthetic, library-based hexapeptide.

Background The hexapeptide 4A6 (Ac-Thr(tBu)-His(Bzl)-Thr(Bzl)-Nle-Glu(OtBu)-Gly-Bza) was isolated from a peptide library constructed to identify peptide-based transport inhibitors of multidrug resistance (MDR) efflux pumps including P-glycoprotein and Multidrug Resistance-associated Protein 1. 4A6 proved to be a substrate but not an inhibitor of these MDR efflux transporters. In fact, 4A6 and related peptides displayed potent cytotoxic activity via an unknown mechanism. Objective To decipher the mode of cytotoxic activity of 4A6. Methods Screening of 4A6 activity was performed against the NCI60 panel of cancer cell lines. Possible interactions of 4A6 with the 26S proteasome were assessed via proteasome activity and affinity labeling, and cell growth inhibition studies with leukemic cells resistant to the proteasome inhibitor bortezomib (BTZ). Results The NCI60 panel COMPARE analysis revealed that 4A6 had an activity profile overlapping with BTZ. Consistently, 4A6 proved to be a selective and reversible inhibitor of ß5 subunit (PSMB5)-associated chymotrypsin-like activity of the 26S proteasome. This conclusion is supported by several lines of evidence: (i) inhibition of chymotrypsin-like proteasome activity by 4A6 and related peptides correlated with their cell growth inhibition potencies; (ii) 4A6 reversibly inhibited functional ß5 active site labeling with the affinity probe BodipyFL-Ahx3L3VS; and (iii) human myeloid THP1 cells with acquired BTZ resistance due to mutated PSMB5 were highly (up to 287-fold) cross-resistant to 4A6 and its related peptides. Conclusion 4A6 is a novel specific inhibitor of the ß5 subunit-associated chymotrypsin-like proteasome activity. Further exploration of 4A6 as a lead compound for development as a novel proteasome-targeted drug is warranted.

Cardiovascular risk management in rheumatoid arthritis patients still suboptimal: the Implementation of Cardiovascular Risk Management in Rheumatoid Arthritis project.

Objective: To assess the 10-year cardiovascular (CV) risk score and to identify treatment and undertreatment of CV risk factors in patients with established RA. Methods: Demographics, CV risk factors and prevalence of cardiovascular disease (CVD) were assessed by questionnaire. To calculate the 10-year CV risk score according to the Dutch CV risk management guideline, systolic blood pressure was measured and cholesterol levels were determined from fasting blood samples. Patients were categorized into four groups: indication for treatment but not treated; inadequately treated, so not meeting goals (systolic blood pressure ⩽140 mmHg and/or low-density lipoprotein ⩽2.5 mmol/l); adequately treated; or no treatment necessary. Results: A total of 720 consecutive RA patients were included, 375 from Reade and 345 from the Antonius Hospital. The mean age of patients was 59 years (s.d. 12) and 73% were female. Seventeen per cent of the patients had a low 10-year CV risk (<10%), 21% had an intermediate risk (10-19%), 53% a high risk (⩾20%) and 9% had CVD. In total, 69% had an indication for preventive treatment (cholesterol-lowering or antihypertensive drugs). Of those, 42% received inadequate treatment and 40% received no treatment at all. Conclusion: Optimal CV risk management remains a major challenge and better awareness and management are urgently needed to reduce the high risk of CVD in the RA population.

What do we miss? ASAS non-responders on anti-TNF therapy show improvement in performance-based physical function.

OBJECTIVE: A prospective study was conducted in order to establish whether AS patients, who are defined as non-responders after 3 months of anti-TNF therapy, show improvement on performance-based tests of physical functioning. METHODS: At baseline and 3 months after the start of anti-TNF therapy, AS patients completed seven performance-based tests of physical functioning, questionnaires on self-reported physical functioning (BASFI) and disease activity (BASDAI), and a pain and a global patient assessment. The concordance between ≥ 20% intra-individual improvement on the performance-based test of physical functioning and (i) response to anti-TNF therapy [Assessment of SpondyloArthritis International Society 20% (ASAS20) response] and (ii) ≥ 20% intra-individual improvement on self-reported physical functioning (BASFI) was assessed. RESULTS: One hundred AS patients were included, of which 82 patients completed all tests at both time points. After 3 months of anti-TNF therapy, 27 (32.9%) patients were categorized as non-responders according to the ASAS20 response criteria. Improvement in performance-based physical functioning was seen in 13 of the 27 non-responders (48.1%) (i.e. n = 13/82 = 15.9% of the total group). Furthermore, 30 (36.6%) patients showed no improvement on self-reported physical functioning (BASFI). However, 17 of the 30 (56.7%) patients did improve on the performance-based tests of physical functioning (i.e. n = 17/82 = 20.7% of the total group). CONCLUSION: After 3 months of anti-TNF therapy, performance-based tests of physical functioning showed improvement in 48.1% of the ASAS20 non-responders. With these performance-based tests, new information on outcome after anti-TNF therapy can be generated. Using performance-based tests alongside the BASFI could have additional value in the evaluation of outcomes for patients receiving anti-TNF therapy.

Metabolic effects of high-dose prednisolone treatment in early rheumatoid arthritis: balance between diabetogenic effects and inflammation reduction.

OBJECTIVE: To investigate the dose-related effects of glucocorticoid treatment on glucose tolerance, beta cell function, and insulin sensitivity in patients with early active rheumatoid arthritis (RA). METHODS: A randomized, controlled, single-blind trial was conducted in 41 patients with early active RA. At the beginning of the trial patients had not been treated for their RA, and were randomized to begin treatment with prednisolone at 60 mg/day or 30 mg/day. Before and at the end of 1 week of treatment, a frequently sampled oral glucose tolerance test was performed. The glucose area under the curve (AUC(G) ) was calculated. In addition, beta cell function and insulin sensitivity parameters were computed. RESULTS: Patients (mean ± SD age 55.5 ± 14.8 years and 54.2 ± 12.6 years in the prednisone 60 mg/day and prednisone 30 mg/day groups, respectively; body mass index 24.5 ± 4.1 kg/m(2) and 25.4 ± 4.2 kg/m(2) , respectively) had active disease at baseline (mean ± SD Disease Activity Score in 44 joints 4.1 ± 0.7 and 4.0 ± 0.8, respectively; median C-reactive protein [CRP] level 14 mg/liter [interquartile range 6-34] and 19 mg/liter [interquartile range 3-39], respectively). In addition, 56% of the patients had impaired glucose tolerance at baseline, and 7% were found to have previously unrecognized type 2 diabetes mellitus (DM). Associations of the AUC(G) with erythrocyte sedimentation rate (ß = 2.430 [95% confidence interval 0.179-4.681], P = 0.04) and with CRP level (ß = 2.358 [95% confidence interval 0.210-4.506], P = 0.03) were demonstrated. Treatment with prednisolone at both dosages reduced CRP levels significantly. The incidence of type 2 DM increased to 24% (P < 0.001) (evenly distributed across the groups). The mean AUC(G) did not change in either treatment arm. Beta cell function improved during prednisone treatment at 60 mg/day (P = 0.02) and at 30 mg/day (P = 0.04). Disease duration was associated with changes in the AUC(G) (ß = 3.626 [95% confidence interval 1.077-6.174], P = 0.007) and with deterioration of the glucose state (odds ratio 1.068 [95% confidence interval 1.017-1.122], P = 0.009). CONCLUSION: In this study, short-term treatment with prednisolone 60 mg or 30 mg per day improved disease activity without deterioration of glucose tolerance in patients with active RA. However, due to individual differences, monitoring is recommended.

Macrophage positron emission tomography imaging as a biomarker for preclinical rheumatoid arthritis: findings of a prospective pilot study.

OBJECTIVE: To conduct a prospective pilot study to determine whether macrophage targeting by 11C-(R)-PK11195 positron emission tomography (PET) can visualize subclinical synovitis in arthralgia patients who have anti-citrullinated protein antibodies (ACPAs). METHODS: Twenty-nine arthralgia patients who were positive for ACPAs but did not have clinical arthritis were studied. High (spatial)-resolution 11C-(R)-PK11195 PET scans of the hands and wrists were performed. For all metacarpophalangeal, proximal interphalangeal, and wrist joints (i.e., 22 joints per patient), tracer uptake was scored semiquantitatively (0-3 scale) by 2 observers who were blinded with regard to the clinical data. Patients were followed up prospectively for 24 months to investigate the development of clinical arthritis. RESULTS: Overall agreement and kappa values for the readings of the 2 observers were, respectively, 97% and 0.91 (95% confidence interval [95% CI] 0.74-1) at the patient level and 99% and 0.81 (95% CI 0.65-0.96) at the joint level. In 4 patients, at least 1 and as many as 5 PET-positive joints (score≥1) were found at baseline. Within 2 years of followup, 9 patients had developed clinical arthritis. This included all 4 patients with positive findings on the 11C-(R)-PK11195 scan, who developed clinical arthritis in the hand/wrist region, as identified on PET scans. Of the 5 remaining arthritis patients with negative findings on PET scans, 2 developed arthritis in the hand joints and 3 developed arthritis at locations outside the field of view of the PET scanner. CONCLUSION: Subclinical arthritis in ACPA-positive arthralgia patients could be visualized by 11C-(R)-PK11195 PET scanning and was associated with development of arthritis within 2 years of followup. This indicates that 11C-(R)-PK11195 PET may be useful in determining arthritis activity in the preclinical phase of RA.

Inactivating PSMB5 mutations and P-glycoprotein (multidrug resistance-associated protein/ATP-binding cassette B1) mediate resistance to proteasome inhibitors: ex vivo efficacy of (immuno)proteasome inhibitors in mononuclear blood cells from patients with rheumatoid arthritis.

Bortezomib (BTZ), a registered proteasome inhibitor (PI) for multiple myeloma, has also been proposed as a potential antirheumatic agent. Its reported side effects, however, make it unappealing for long-term administration, and resistance may also develop. To overcome this, second-generation PIs became available. Here, we investigated whether a novel class of peptide epoxyketone-based PIs, including carfilzomib, N-((S)-3-methoxy-1-(((S)-3-methoxy-1-(((S)-1-((R)-2-methyloxiran-2-yl)-1-oxo-3-phenylpropan-2-yl)amino)-1-oxopropan-2-yl)amino)-1-oxopropan-2-yl)-2-methylthiazole-5-carboxamide (ONX0912), and (S)-3-(4-methoxyphenyl)-N-((S)-1-((S)-2-methyloxiran-2-yl)-1-oxo-3-phenylpropan-2-yl)-2-((S)-2-(2-morpholinoacetamido)propanamido)propanamide (ONX0914), might escape two established BTZ-resistance mechanisms: 1) mutations in the proteasome ß5 subunit (PSMB5) targeted by these PIs, and 2) drug efflux mediated by ATP-binding cassette transporters. THP1 myeloid sublines with acquired resistance to BTZ (54- to 235-fold) caused by mutations in the PSMB5 gene displayed marked cross-resistance but less pronounced cross-resistance to carfilzomib (9- to 32-fold), ONX0912 (39- to 62-fold), and ONX0914 (27- to 97-fold). As for ATP-binding cassette transporter-mediated efflux, lymphoid CEM/VLB cells with P-glycoprotein (Pgp)/multidrug resistance 1 overexpression exhibited substantial resistance to carfilzomib (114-fold), ONX0912 (23-fold), and ONX0914 (162-fold), whereas less resistance to BTZ (4.5-fold) was observed. Consistently, ß5 subunit-associated chymotrypsin-like proteasome activity was significantly less inhibited in these CEM/VLB cells. Ex vivo analysis of peripheral blood mononuclear cells from therapy-naive patients with rheumatoid arthritis revealed that, although basal Pgp levels were low, P-glycoprotein expression compromised the inhibitory effect of carfilzomib and ONX0914. However, the use of P121 (reversin 121), a Pgp transport inhibitor, restored parental cell inhibitory levels in both CEM/VLB cells and peripheral blood mononuclear cells. These results indicate that the pharmacologic activity of these PIs may be hindered by drug resistance mechanisms involving PSMB5 mutations and PI extrusion via Pgp.

Aggressive therapy in patients with early arthritis results in similar outcome compared with conventional care: the STREAM randomized trial.

OBJECTIVE: To compare the effects of aggressive tight control therapy and conventional care on radiographic progression and disease activity in patients with early mild inflammatory arthritis. METHODS: Patients with two to five swollen joints, Sharp-van der Heijde radiographic score (SHS) <5 and symptom duration ≤2 years were randomized between two strategies. Patients with a definite non-RA diagnosis were excluded. The protocol of the aggressive group aimed for remission (DAS < 1.6), with consecutive treatment steps: MTX, addition of adalimumab and combination therapy. The conventional care group followed a strategy with traditional DMARDs (no prednisone or biologics) without DAS-based guideline. Outcome measures after 2 years were SHS (primary), remission rate and HAQ score (secondary). RESULTS: Eighty-two patients participated (60% ACPA positive). In the aggressive group (n = 42), 19 patients were treated with adalimumab. In the conventional care group (n = 40), 24 patients started with hydroxychloroquin (HCQ), 2 with sulfasalazine (SSZ) and 14 with MTX. After 2 years, the median SHS increase was 0 [interquartile range (IQR) 0-1.1] and 0.5 (IQR 0-2.5), remission rates were 66 and 49% and HAQ decreased with a mean of -0.09 (0.50) and -0.25 (0.59) in the aggressive and conventional care group, respectively. All comparisons were non-significant. CONCLUSION: In patients with early arthritis of two to five joints, both aggressive tight-control therapy including adalimumab and conventional therapy resulted in remission rates around 50%, low radiographic damage and excellent functional status after 2 years. However, full disease control including radiographic arrest in all patients remains an elusive target even in moderately active early arthritis. Trial registration. Dutch Trial Register, http://www.trialregister.nl/, NTR 144.

Sustained drug-free remission in rheumatoid arthritis after DAS-driven or non-DAS-driven therapy: a comparison of two cohort studies.

OBJECTIVES: To compare the prevalence of and predictors for sustained drug-free remission in two cohorts of patients with recent-onset RA treated with DAS-driven therapy or non-DAS-driven therapy. METHODS: Sustained drug-free remission was assessed after 5 years of follow-up in 508 patients treated with DAS-driven therapy (DAS ≤ 2.4) in a randomized treatment cohort, and in 424 patients who received non-DAS-driven therapy in a prospective inception cohort. The design of the DAS-driven cohort required systematic joint assessments with DAS-driven restart of therapy. Predictors for remission were identified by univariable and multivariable logistic regression in each cohort separately and in a combined multivariate logistic regression analysis corrected for propensity scores, including a sensitivity analysis on patients receiving initial monotherapy. RESULTS: Patients in the DAS-driven cohort had more active disease at baseline, but the prevalence of sustained drug-free remission was similar after DAS-driven (9.8%) and non-DAS-driven therapy (10.6%). Among patients with ACPA, drug-free remission was more frequently achieved after DAS-driven than after non-DAS-driven therapy (5.4 vs. 2.1%, OR = 2.68, 95% CI 0.97, 7.43). Absence of ACPA and short symptom duration were independent predictors for sustained drug-free remission in both cohorts. Initial treatment choice and inclusion period were not predictive. The sensitivity analysis yielded comparable results. CONCLUSION: Retrospectively comparing a DAS-driven to a non-DAS-driven therapy cohort, the occurrence and predictors of sustained drug-free remission were similar. The DAS-driven cohort had a more unfavourable prognosis. DAS-driven therapy may improve the chance of sustained drug-free remission in ACPA-positive patients with recent-onset RA.

Development of the anti-citrullinated protein antibody repertoire prior to the onset of rheumatoid arthritis.

OBJECTIVE: To examine how anti-citrullinated protein antibody (ACPA) epitope spreading takes place prior to the onset of clinical rheumatoid arthritis (RA), and to analyze the pattern of autoantigen reactivity at the beginning of the immune response. METHODS: Multiple consecutive serum samples from 79 RA patients who had donated blood before disease onset were available for analysis. Fifty-three patients tested positive for ACPAs prior to the onset of clinical RA. For these patients, a median of 6 (interquartile range 4-9) sequential pre-RA serum samples obtained 1-2 years apart were tested. Reactivity to 5 distinct citrullinated peptides was measured by enzyme-linked immunosorbent assay. Two peptides were derived from fibrinogen, 1 from vimentin, 1 from α-enolase, and 1 from filaggrin. RESULTS: In 25 of 53 ACPA-positive patients, seroconversion from ACPA absence to ACPA presence was observed. In 72% of these patients, the immune response started with reactivity to 1 peptide, without preference for a particular peptide. The number of peptides recognized increased over time, without a dominant epitope-spreading pattern. ACPAs appeared in low levels several years prior to the diagnosis of RA. Antibody titers increased markedly ∼2-4 years before diagnosis. CONCLUSION: Our findings indicate that ACPA epitope spreading occurs over several years prior to the onset of clinical RA. The initial autoimmune response is mostly directed toward only 1 autoantigen, but this is not always the same antigen. The marked increase in ACPA titers a few years prior to the diagnosis of RA suggests a second stage in disease development, which might be due to a variety of factors.

Parvovirus B19 in pregnancy: prenatal diagnosis and management of fetal complications.

PURPOSE OF REVIEW: Parvovirus B19 infection is often considered a mild and self-limiting disease of minor clinical importance. This review aims to raise awareness of recently discovered potentially devastating consequences of this infection in pregnancy, and provides updated guidelines on diagnosis and management. RECENT FINDINGS: In contrast to previous beliefs, parvovirus B19 infection during any stage of pregnancy may not only cause fetal death, but may also result in severe and irreversible neurological sequelae in survivors. Improved diagnostic techniques allow more reliable and earlier diagnosis of fetal disease. SUMMARY: Clinicians need to be aware of the risk of adverse outcome of parvovirus B19 infection in pregnancy, and sometimes the long interval between exposure and fetal symptoms. Accurate diagnosis using PCR and weekly ultrasound checks ups with Doppler measurement of middle cerebral artery flow velocity up to 20 weeks postexposure may improve detection of fetal disease. More timely treatment likely results in improved outcome.

Drug-free remission: is it already possible?

PURPOSE OF REVIEW: To give an overview of recently published articles covering drug-free remission in rheumatoid arthritis (RA). RECENT FINDINGS: Recent studies covering drug-free remission showed differences in numbers studied, remission definition, disease duration and medication used. Drug-free remission was reported in 9-29%. Only two out of four studies reported on patients who restarted medication due to a disease flare or loss of remission, which occurred in 45-46%. In the BeSt study, remission or low disease activity was achieved again after retreatment within 6 months in 96%. In the Finnish Early Rheumatoid Arthritis study, none of the patients achieved remission after retreatment; their mean Disease Activity Score (DAS28) was 3.68. Joint damage progression was not higher in patients who restarted medication when compared to patients in sustained drug-free remission or patients with continued treatment. Anticitrullinated protein antibody, rheumatoid factor or shared epitope negativity and short symptom duration were independent predictors of successful drug-free remission in more than one cohort. SUMMARY: Drug-free remission can be achieved and sustained in a small group of RA patients. In early RA, retreatment is successful in the majority of patients. Disease flare after cessation of medication does not seem to increase joint damage progression. Sustained drug-free remission is predicted by autoantibody and shared epitope negativity and short disease duration before treatment initiation.

The presence or absence of antibodies to infliximab or adalimumab determines the outcome of switching to etanercept.

OBJECTIVE: The aim of this study was to test the hypothesis that the reason for non-response (caused by immunogenicity or not) to a first tumour necrosis factor (TNF) inhibitor defines whether a second TNF inhibitor will be effective. METHODS: This cohort study consisted of 292 consecutive patients with rheumatoid arthritis (RA), all treated with etanercept. A total of 89 patients (30%) were treated previously with infliximab or adalimumab ('switchers'), and the remaining 203 (70%) were anti-TNF naive. All switchers were divided into two groups: with and without antibodies against the previous biological. Differences in clinical response to etanercept between switchers with and without antibodies and patients who were anti-TNF naive were assessed after 28 weeks of treatment using changes in Disease Activity Score in 28 joints (DAS28). RESULTS: After 28 weeks of treatment, response to etanercept did not differ between patients who were anti-TNF naive and switchers with anti-drug antibodies (ΔDAS28=2.1 ± 1.3 vs ΔDAS28=2.0 ± 1.3; p = 0.743). In contrast, switchers without anti-drug antibodies had a diminished response to etanercept treatment compared to patients who were TNF naive (ΔDAS28 =1.2±1.3 vs ΔDAS28 = 2.1 ± 1.3; p = 0.001) and switchers with antibodies (ΔDAS28 =1.2±1.3 vs ΔDAS28 = 2.0 ± 1.3; p = 0.017). CONCLUSION: Patients with RA with an immunogenic response against a first TNF-blocking agent had a better clinical response to a subsequent TNF blocker compared to patients with RA without anti-drug antibodies. Hence, determining immunogenicity can be helpful in deciding in which patient switching could be beneficial and can be part of a personalised treatment regimen.

The impact of four dynamic, goal-steered treatment strategies on the 5-year outcomes of rheumatoid arthritis patients in the BeSt study.

OBJECTIVE: To compare clinical and radiological outcomes of four dynamic treatment strategies in recent-onset rheumatoid arthritis (RA) after 5 years follow-up. METHODS: 508 patients with recent-onset RA were randomly assigned into four treatment strategies: sequential monotherapy; step-up combination therapy; initial combination with prednisone; initial combination with infliximab. Treatment adjustments were made based on 3-monthly disease activity score (DAS) measurements (if DAS >2.4 next treatment step; if DAS ≤ 2.4 during ≥ 6 months taper to maintenance dose; if DAS <1.6 during ≥ 6 months stop antirheumatic treatment). Primary and secondary outcomes were functional ability, joint damage progression, health-related quality of life and (drug-free) remission percentages. RESULTS: After 5 years, 48% of patients were in clinical remission (DAS <1.6) and 14% in drug-free remission, irrespective of initial treatment. After an earlier improvement in functional ability and quality of life with initial combination therapy, from 1 year onwards clinical outcomes were comparable across the groups and stable during 5 years. The initial combination groups showed less joint damage in year 1. In years 2-5 annual progression was comparable across the groups. After 5 years, initial combination therapy resulted in significantly less joint damage progression, reflecting the earlier clinical response. CONCLUSION: Irrespective of initial treatment, an impressive improvement in clinical and radiological outcomes of RA patients can be achieved with dynamic treatment aimed at reducing disease activity, leading to 48% remission, 14% drug-free remission and sustained functional improvement. Starting with combination therapy resulted in earlier clinical improvement and less joint damage without more toxicity.

Pharmacological induction of interferon type I activity following treatment with rituximab determines clinical response in rheumatoid arthritis.

OBJECTIVE: Despite the fact that rituximab depletes B cells in all treated patients with RA, not all patients show a favourable clinical response. The goal of this study was to provide insight into pharmacological changes in peripheral blood that are associated with clinical response to rituximab. METHODS: Gene expression profiling was performed on peripheral blood RNA of 13 patients with RA (test group) using Illumina HumanHT beadchip microarrays. An independent group of nine patients was used for validation using TaqMan quantitative PCR. Clinical responder status was determined after 6 months using change in 28-joint Disease Activity Score (ΔDAS28) and European League Against Rheumatism (EULAR) response criteria. Significance analysis of microarrays and ontology analysis were used for data analysis and interpretation. RESULTS: Pharmacogenomic analyses demonstrated marked interindividual differences in the pharmacological responses at 3 and 6 months after start of treatment with rituximab. Interestingly, only differences in the regulation of type I interferon (IFN)-response genes after 3 months correlated with the ΔDAS28 response. Good responders (DAS>1.2; n=7) exhibited a selective increase in the expression of type I IFN-response genes, whereas this activity was unchanged or hardly changed in non-responders (DAS<1.2; n=6) (p=0.0040 at a cut-off of 1.1-fold induction). Similar results were obtained using EULAR response criteria. These results were validated in an independent cohort of nine patients (five non-responders and four responders, p=0.0317). CONCLUSIONS: A good clinical response to rituximab in RA is associated with a selective drug-induced increase in type I IFN-response activity in patients with RA. This finding may provide insight in the biological mechanism underlying the therapeutic response to rituximab.

The extent of the anti-citrullinated protein antibody repertoire is associated with arthritis development in patients with seropositive arthralgia.

OBJECTIVES: To determine the fine specificity of anti-citrullinated protein antibodies (ACPA) in the early phase of arthritis development, the ACPA repertoire in arthralgia patients and the association with arthritis development were studied. METHODS: A total of 244 patients with arthralgia positive for anti-cyclic citrullinated peptide antibodies (aCCPs) and/or IgM rheumatoid factor (IgM-RF), without arthritis were included. Development of arthritis was defined as presence of one or more swollen joints at clinical examination during follow-up. Sera were tested at baseline for reactivity to five citrullinated peptides derived from fibrinogen (three), vimentin (one) and α-enolase (one) and five corresponding arginine peptides in an ELISA. RESULTS: In all, 69 patients (28%) developed arthritis in a median of 3 joints after a median follow-up of 11 (IQR 5-20) months. Reactivity to each peptide was significantly associated with arthritis development (p<0.001). The ACPA repertoire did not differ between patients who did or did not develop arthritis. Among aCCP-positive patients, patients recognising two or more additional citrullinated peptides developed arthritis more often (p=0.04). The number of recognised peptides was positively associated with the aCCP level (p<0.001). Crossreactivity between different peptides was minimal. CONCLUSIONS: Arthritis development is not associated with recognition of a specific citrullinated peptide once joint complaints are present. The ACPA repertoire in some patients with arthralgia is expanded. High aCCP levels are associated with a qualitatively broad ACPA repertoire. Patients with an extended ACPA repertoire have a higher risk of developing arthritis.

Gene expression profiling in autoantibody-positive patients with arthralgia predicts development of arthritis.

OBJECTIVE: To identify molecular features associated with the development of rheumatoid arthritis (RA), to understand the pathophysiology of preclinical development of RA, and to assign predictive biomarkers. METHODS: The study group comprised 109 anti-citrullinated protein antibody (ACPA)- and/or rheumatoid factor-positive patients with arthralgia who did not have arthritis but were at risk of RA, and 25 patients with RA. The gene expression profiles of blood samples obtained from these patients were determined by DNA microarray analysis and quantitative polymerase chain reaction. RESULTS: In 20 of the 109 patients with arthralgia who were at risk of RA, arthritis developed after a median of 7 months. Gene expression profiling of blood cells revealed heterogeneity among the at-risk patients, based on differential expression of immune-related genes. This report is the first to describe gene signatures relevant to the development of arthritis. Signatures significantly associated with arthritis development were involved in interferon (IFN)-mediated immunity, hematopoiesis, and chemokine/cytokine activity. Logistic regression analysis revealed that the odds ratio (OR) for developing arthritis within 12 months was 21.0 (95% confidence interval [95% CI] 2.8-156.1 [P = 0.003]) for the subgroup characterized by increased expression of genes involved in IFN-mediated immunity and/or cytokine/chemokine-activity. Genes involved in B cell immunology were associated with protection against progression to arthritis (OR 0.38, 95% CI 0.21-0.70 [P = 0.002]). These processes were reminiscent of those in patients with RA, implying that the preclinical phase of disease is associated with features of established disease. CONCLUSION: The results of this study indicate that IFN-mediated immunity, hematopoiesis, and cell trafficking specify processes relevant to the progression of arthritis independent of ACPA positivity. These findings strongly suggest that certain gene signatures have value for predicting the progression to arthritis, which will pave the way to preventive medicine.

Bone turnover is adequately suppressed in osteoporotic patients treated with bisphosphonates in daily practice.

BACKGROUND: Monitoring osteoporosis therapy by measurement of bone turnover markers (BTMs) might detect non-compliance in an earlier stage of anti-osteoporosis treatment and improve persistence. METHODS: BTMs were measured in two groups. The first group consisted of patients newly diagnosed with osteoporosis and starting treatment. We observed which proportion of patients had a decrease of serum levels of procollagen type 1 N-terminal propeptide (P1NP) and C-terminal crosslinking telopeptide (CTX) greater than the least significant change (LSC) after 3 months of treatment. Secondly, we determined which proportion of patients who were treated with bisphosphonates for ≥ 3 months reached the biological goal of therapy, BTMs in the lower half of the normal premenopausal range. P1NP and CTX were also measured in a reference population of 34 healthy premenopausal women. RESULTS: In the first group 31 patients were included, in 25 patients (81%) levels of both markers decreased with ≥ LSC, in the other patients a possible explanation was found.In the second group 95 patients were included, in 95% the serum P1NP levels and CTX levels were in the lower half of the premenopausal range. In 6 of the 7 patients with a level above the premenopausal range a possible explanation was found. CONCLUSION: A decrease in bone turnover ≥ LSC can be observed in the majority of newly treated patients. In chronically treated patients, 95% have a bone turnover in the premenopausal range. In most patients with inadequate suppression of BTMs during bisphosphonate treatment, an explanation was found. Monitoring treatment effect with BTMs in daily practice is feasible, and might be an additive tool in improving therapy compliance.

Development of antidrug antibodies against adalimumab and association with disease activity and treatment failure during long-term follow-up.

CONTEXT: Short-term data on the immunogenicity of monoclonal antibodies showed associations between the development of antidrug antibodies and diminished serum drug levels, and a diminished treatment response. Little is known about the clinical relevance of antidrug antibodies against these drugs during long-term follow-up. OBJECTIVE: To examine the course of antidrug antibody formation against fully human monoclonal antibody adalimumab and its clinical relevance during long-term (3-year) follow-up of patients with rheumatoid arthritis (RA). DESIGN, SETTING, AND PATIENTS: Prospective cohort study February 2004-September 2008; end of follow-up was September 2010. All 272 patients were diagnosed with RA and started treatment with adalimumab in an outpatient clinic. MAIN OUTCOME MEASURES: Disease activity was monitored and trough serum samples were obtained at baseline and 8 time points to 156 weeks. Serum adalimumab concentrations and antiadalimumab antibody titers were determined after follow-up. Treatment discontinuation, minimal disease activity, and clinical remission were compared for patients with and without antiadalimumab antibodies. RESULTS: After 3 years, 76 of 272 patients (28%) developed antiadalimumab antibodies--51 of these (67%) during the first 28 weeks of treatment. Patients without antiadalimumab antibodies had much higher adalimumab concentrations (median, 12 mg/L; IQR, 9-16 mg/L) compared with patients with antibody titers from 13 to 100 AU/mL (median, 5 mg/L; IQR, 3-9 mg/L; regression coefficient, -4.5; 95% CI, -6.0 to -2.9; P < .001) and also those greater than 100 AU/mL (median, 0 mg/L; IQR, 0-3 mg/L; regression coefficient, -7.1; 95% CI, -8.4 to -5.8; P < .001). Patients with antiadalimumab antibodies more often discontinued participation due to treatment failure (n = 29 [38%]; hazard ratio [HR], 3.0; 95% CI, 1.6-5.5; P < .001) compared with antiadalimumab antibody-negative ones (n = 28 [14%]). Ninety-five of 196 patients (48%) without antiadalimumab antibodies had minimal disease activity vs 10 of 76 patients (13%) with antiadalimumab antibodies; patients with antiadalimumab antibodies less often had sustained minimal disease activity score in 28 joints (DAS28) (< 3.2; HR, 3.6; 95% CI, 1.8-7.2; P < .001) compared with antiadalimumab antibody-negative ones. Three of 76 patients (4%) with antiadalimumab antibodies achieved sustained remission compared with 67 of 196 (34%) antiadalimumab antibody-negative ones; patients with antiadalimumab antibodies less often achieved remission (DAS28 < 2.6; HR, 7.1; 95% CI, 2.1-23.4; P < .001) compared with antiadalimumab antibody-negative ones. CONCLUSION: Among outpatients with RA in whom adalimumab was started over 3 years, the development of antidrug antibodies was associated with lower adalimumab concentration and lower likelihood of minimal disease activity or clinical remission.

Tumour necrosis factor {alpha} blockade reduces circulating N-terminal pro-brain natriuretic peptide levels in patients with active rheumatoid arthritis: results from a prospective cohort study.

BACKGROUND: Patients with rheumatoid arthritis (RA) are at increased risk of heart failure and vascular events. Small increases in circulating N-terminal pro-brain natriuretic peptide (NT-proBNP) are associated with an increased risk of a cardiovascular event, and high levels signal left ventricular dysfunction. Data on the effects of tumour necrosis factor alpha(TNFalpha) blocking agents on circulating NT-proBNP levels in patients with active RA are lacking but may be informative. METHODS: 171 consecutive patients with RA (28-joint disease activity score >3.2) without congestive heart failure (NYHA class III or IV) were scheduled to receive adalimumab once every 2 weeks. Serum NT-proBNP concentrations were measured simultaneously on stored baseline and 16-week samples. Paired sample t tests were used to observe differences in biomarkers before and after adalimumab administration. Correlations between the biomarkers and changes in circulating log NT-proBNP levels were evaluated with the Pearson test and multivariable linear regression analyses of correlates were performed (forward selection procedure). RESULTS: Circulating levels of NT-proBNP decreased significantly after 16 weeks of adalimumab administration (median NT-proBNP 83.0 pg/ml vs 69.5 pg/ml, p=0.004). Changes in NT-proBNP levels were associated with changes in pulse pressure (r=0.18, p=0.02), systolic blood pressure (r=0.16, p=0.04) and erythrocyte sedimentation rate (r=0.18, p=0.02). On multivariable analysis, changes in pulse pressure and erythrocyte sedimentation rate remained independently associated with changes in circulating NT-proBNP levels. CONCLUSIONS: These observations show that blocking TNFalpha in patients with RA without evident heart failure decreases NT-proBNP levels by about 18%. This suggests no treatment-induced deterioration in cardiac function and a potential cardiovascular risk benefit.

Baseline RANKL:OPG ratio and markers of bone and cartilage degradation predict annual radiological progression over 11 years in rheumatoid arthritis.

OBJECTIVE: To determine to what extent baseline measurements of the ratio receptor activator of nuclear factor-kappaB ligand (RANKL):osteoprotegerin (OPG) and C-terminal cross linking of type-I and type-II (CTX-I and CTX-II), in addition to traditional markers of disease severity, could predict annual radiological progression. METHODS: A cohort of 155 patients with early, active, untreated rheumatoid arthritis (RA) who participated in the Combination Therapy in Early Rheumatoid Arthritis trial (COBRA trial) was followed up for 11 years. Urine was sampled at baseline and after 3 months from the start of treatment and analysed for CTX-I and CTX-II. Baseline serum samples were analysed for RANKL and OPG. Available traditional markers of disease severity included baseline measurements of erythrocyte sedimentation rate, rheumatoid factor and baseline radiological damage. A digital database of frequent radiographs was available, scored according to the Sharp/van der Heijde method. Individual annual progression rates were calculated and used as outcome variable. Multiple linear regression analyses identified the strongest predictors of annual radiological progression. RESULTS: In multivariable analyses the RANKL:OPG ratio and CTX-I or CTX-II proved to be independent predictors of annual radiological damage over 11 years. The prediction of annual radiological progression was strongest when the RANKL:OPG ratio and CTX-I or CTX-II were evaluated in the same model (36-39% explained variance). Adding the effect of treatment at 3 months to the baseline models improved the predictive ability of the models up to 44-46%. CONCLUSION: Unfavourable baseline levels of the RANKL:OPG ratio as well as CTX-I and CTX-II in patients with early, active, untreated RA are strong independent predictors of rapid and persistent damage progression over the 11-year follow-up. Early improvement in bone markers by treatment predicts a better outcome.