Impact of high rheumatoid factor levels on treatment outcomes with certolizumab pegol and adalimumab in patients with rheumatoid arthritis.

OBJECTIVE: To assess the impact of baseline rheumatoid factor (RF) level on drug concentrations and efficacy of certolizumab pegol (CZP; tumour necrosis factor inhibitor [TNFi] without a crystallisable fragment [Fc]) and adalimumab (ADA; Fc-containing TNFi) in patients with rheumatoid arthritis (RA). METHODS: The phase 4 EXXELERATE study (NCT01500278) was a 104-week, randomised, single-blind (double-blind until week 12; investigator-blind thereafter), head-to-head study of CZP vs ADA in patients with RA. In this post hoc analysis, we report drug concentration and efficacy outcomes stratified by baseline RF quartile (≤Q3 or >Q3). RESULTS: Baseline data by RF quartiles were available for 453 CZP-randomised and 454 ADA-randomised patients (≤Q3: ≤204 IU/ml; >Q3: >204 IU/ml). From week 12, the area under the curve (AUC) of ADA concentration was lower in patients with RF > 204 IU/ml vs patients with RF ≤ 204 IU/ml; the AUC of CZP concentration was similar in patients with RF ≤ 204 IU/ml and >204 IU/ml. For patients with RF ≤ 204 IU/ml, disease activity score (DAS28)-C-reactive protein (CRP) was similar between CZP- and ADA-treated patients through week 104. For patients with RF > 204 IU/ml, mean DAS28-CRP was lower in CZP- vs ADA-treated patients at week 104. The proportion of patients with RF > 204 IU/ml achieving DAS28-CRP low disease activity at week 104 was greater in CZP- vs ADA-treated patients. CONCLUSION: CZP was associated with maintained drug concentration and efficacy in patients with RA and high RF and may therefore be a more suitable therapeutic option than TNFis with an Fc fragment in these patients.

Efficacy of certolizumab pegol across baseline rheumatoid factor subgroups in patients with rheumatoid arthritis: Post-hoc analysis of clinical trials.

AIM: Certolizumab pegol (CZP), an Fc-free, PEGylated tumor necrosis factor inhibitor (TNFi), has shown rapid and sustained reduction in signs and symptoms of rheumatoid arthritis (RA). Elevated rheumatoid factor (RF) level has been associated with RA disease progression and poorer TNFi response. We assessed the efficacy of CZP in patients with early and established RA across baseline RF levels. METHODS: This post-hoc analysis included data from 6 trials: C-OPERA (NCT01451203), pooled RAPID trials (RAPID-1 [NCT00152386], RAPID-2 [NCT00160602], J-RAPID [NCT00791999], RAPID-C [NCT02151851]), and EXXELERATE (NCT01500278). Patients who received CZP or placebo/comparator with methotrexate (MTX) were categorized by baseline RF quartiles. Efficacy was assessed with Disease Activity Score-28 erythrocyte sedimentation rate (DAS28-ESR). RESULTS: Overall, 316, 1537, and 908 patients were included in C-OPERA, pooled RAPID trials, and EXXELERATE, respectively. Patient demographics and baseline disease characteristics were similar between treatment groups and across RF quartiles. DAS28-ESR low disease activity (LDA) and remission (REM) rates were numerically higher in the CZP + MTX group than PBO + MTX group at weeks 12 and 24, across RF quartiles. LDA and REM rates in the CZP + MTX groups were comparable across RF quartiles at weeks 12 and 24. Mean DAS28-ESR decreased from week 0 to week 24 in the CZP + MTX groups, across RF quartiles. CONCLUSION: CZP showed steady efficacy across baseline RF quartiles in patients with early and established RA, over 24 weeks. CZP treatment may be considered in patients with RA irrespective of baseline RF levels and time from diagnosis.

Combined evaluation of fecal calprotectin and C-reactive protein as a therapeutic target in the management of patients with Crohn's disease.

OBJECTIVES: Proper management of the inflammatory process in Crohn's disease (CD) results in lower rates of complications. The objective of this study was to investigate the performance of isolated and combined use of fecal calprotectin (FC) and serum levels of C-reactive protein (CRP) as markers of inflammatory activity in CD and the possibility of their use as a therapeutic target. PATIENTS AND METHODS: Patients with CD and indication for colonoscopy were prospectively enrolled in the study and allocated according to the presence or absence of endoscopic inflammatory activity. The correlation between FC and CRP levels and the Simplified Endoscopic Score of Crohn's Disease (SES-CD) was performed, and the accuracy of these markers was evaluated for the diagnosis of inflammatory activity, when used alone or in series. RESULTS: Eighty colonoscopies were performed in patients with CD. The FC cut-off value of 155µg/g showed high sensitivity (96%) and accuracy (78%) for the diagnosis of endoscopic activity. For CRP, the value of 6.7mg/L demonstrated sensitivity of 75% and specificity of 67%. The sequential usage of these markers (FC+CRP) showed greater specificity (82%) when compared to the use of these markers alone. Depending on the probability of inflammatory activity, different scenarios were used to evaluate the performance of these markers and an algorithm is proposed. DISCUSSION: Combined analysis of FC and CRP, when performed consecutively, allows decisions to be made with a high degree of certainty and even eliminates the need for colonoscopy in many situations.

Meloxicam ameliorates the systemic inflammatory response syndrome associated with experimentally induced endotoxemia in adult donkeys.

BACKGROUND: Little information is available about endotoxemia in donkeys. Characterizing the systemic inflammatory response (SIRS) to lipopolysaccharide (LPS) in donkeys would provide valuable clinical and therapeutic information. The effects of meloxicam on endotoxemia have not been studied in this species. OBJECTIVES: To study the pathophysiology and gene expression associated with experimentally induced endotoxemia, and evaluate the effects of meloxicam on experimentally induced endotoxemia in donkeys and in equine monocyte cultures. ANIMALS: Six healthy adult female donkeys. METHODS: Endotoxemia was induced by an IV infusion of LPS for 30 minutes. Animals either received 20 mL of saline or 0.6 mg/kg of meloxicam IV after LPS infusion. The experiments lasted 6 hours. Blood samples were collected serially for hematology, serum biochemistry, interleukin measurement, and leukocyte gene expression analysis. Vital signs were recorded throughout the study. Monocyte cultures were used to test the effects of meloxicam on LPS-activated monocytes. RESULTS: Lipopolysaccharide induced fever, leukopenia, and neutropenia of similar magnitude in both groups, but meloxicam attenuated increases in plasma lactate, tumor necrosis factor-alpha (TNFα), and interleukin 1ß concentrations compared to controls. No differences were detected between groups for cytokine mRNA expression. Furthermore, meloxicam decreased TNFα release in LPS-activated monocyte cultures. CONCLUSIONS AND CLINICAL IMPORTANCE: Meloxicam could be a feasible option for the treatment of endotoxemia and SIRS in donkeys. Additional studies are necessary to investigate possible meloxicam-related posttranscriptional regulation and to compare this drug with other nonsteroidal anti-inflammatory drugs (NSAIDs) in animals with endotoxemia.

Adalimumab for Induction of Histological Remission in Moderately to Severely Active Ulcerative Colitis.

BACKGROUND: Histological remission represents a target distinct from endoscopic healing in ulcerative colitis (UC) and seems a better predictor of clinical outcomes. AIMS: The aim of this study was to assess the ability of adalimumab to achieve histological remission in UC patients. METHODS: Single-center, retrospective, open-label study of patients treated with adalimumab. Eligible patients were anti-TNF naïve adults with moderately to severely active UC. The Mayo score including endoscopy was performed at baseline and weeks 8 and 52. Histological activity was scored using the Geboes Index. The primary endpoint was histological remission, defined as a Geboes grade ≤ 3.0, at week 52. RESULTS: We included 34 patients. At week 8, 6 of 34 patients (17.6%) achieved histological remission. At week 52, 9 patients (26.5%, intention to treat; 31%, per protocol) had histological remission. Patients had a significant and progressive reduction in the most severe subgrades of Geboes Index from baseline at weeks 8 and 52. At weeks 8 and 52, 50 and 61.8% of patients achieved mucosal healing (Mayo endoscopic subscore 0-1). All patients who achieved histological remission also had mucosal healing. At week 8, 85.3 and 20.6% of patients achieved clinical response (decrease in Mayo score ≤ 3 points) or remission (Mayo score ≤ 2), respectively. At week 52, the corresponding values were 67.6 and 52.9%, respectively. At week 52, agreement between histological remission and mucosal healing was fair (kappa 0.293). Agreement between histological remission and Mayo endoscopic subscore 0 was good (kappa 0.71). CONCLUSIONS: Adalimumab was able to achieve histological remission in anti-TNF naïve patients with moderately to severely active UC.

Biology of anti-TNF agents in immune-mediated inflammatory diseases: therapeutic implications.

Biologics are increasingly being used to modify the course of immune-mediated inflammatory diseases. Some main agents are monoclonal antibodies and a fusion-protein that target TNF. This group includes adalimumab, infliximab, certolizumab pegol, golimumab and etanercept. Although the efficacy of anti-TNFs is supported by numerous randomized clinical trials, their pharmacokinetics depend on many factors, in particular immunogenicity, which can cause marked and rapid clearance and a consequent decrease in efficacy. Kinetics involve receptors that recognize the Fc fragment of the antibody and are responsible for various processes. Pharmacological advances permit optimizing the pharmacokinetics of anti-TNFs. In this review, we examine the kinetics of anti-TNF biologics, and consequent therapeutic implications, and overview some latest developments in the field. First draftsubmitted: 17 May 2016; Accepted for publication: 15 September2016; Published online: 14 October 2016.

Causes of CNS inflammation and potential targets for anticonvulsants.

Inflammation is one of the most important endogenous defence mechanisms in an organism. It has been suggested that inflammation plays an important role in the pathophysiology of a number of human epilepsies and convulsive disorders, and there is clinical and experimental evidence to suggest that inflammatory processes within the CNS may either contribute to or be a consequence of epileptogenesis. This review discusses evidence from human studies on the role of inflammation in epilepsy and highlights potential new targets in the inflammatory cascade for antiepileptic drugs. A number of mechanisms have been shown to be involved in CNS inflammatory reactions. These include an inflammatory response at the level of the blood-brain barrier (BBB), immune-mediated damage to the CNS, stress-induced release of inflammatory mediators and direct neuronal dysfunction or damage as a result of inflammatory reactions. Mediators of inflammation in the CNS include interleukin (IL)-1ß, tumour necrosis factor-α, nuclear factor-κB and toll-like receptor-4 (TLR4). IL-1ß, BBB and high-mobility group box-1-TLR4 signalling appear to be the most promising targets for anticonvulsant agents directed at inflammation. Such agents may provide effective therapy for drug-resistant epilepsies in the future.

Thiopurine methyltransferase activity in Spain: a study of 14,545 patients.

We sought to assess the activity of thiopurine methyltransferase (TPMT) in 14,545 Spanish patients with different diseases amenable to treatment with azathioprine/6-mercaptopurine (6-MP), and to evaluate the proportion of patients with low TPMT activity and therefore a higher risk of myelotoxicity with these drugs. TPMT activity in red blood cells (RBCs) was measured by a radiochemical method. The association between several clinical variables and TPMT activity was assessed by multiple linear regression. We included 14,545 patients: autoimmune hepatitis (n=359 patients), inflammatory bowel disease (n=7,046), multiple sclerosis (n = 814), myasthenia gravis (n=344), pemphigus (n=133), and other diseases (n=5,849). Mean TPMT activity was 20.1 +/- 6 U/mL, but differed depending on the disease (P<.001). TPMT distribution was low (<5) in 0.5%; intermediate (5.0-13.7) in 11.9%; or high (>or=13.8) in 87.6%. Only when TPMT activity was considered separately in each disease did it reveal a normal distribution. In the multivariate analysis, gender, hematocrit, and treatment with 5-aminosalicylates/steroids/azathioprine/6-MP statistically influenced TPMT activity, although, probably, in a clinically irrelevant manner. This study shows, in a large sample of 14,545 patients, that 0.5% had low TPMT activity, indicating a higher risk of myelotoxicity with azathioprine/6-MP, a figure similar or slightly higher than that reported in other areas. Nevertheless, the trimodal distribution of TPMT activity varied depending on disease, and the proportion of patients with low activity values ranged from 0-0.8%. The drugs prescribed for the treatment of autoimmune diseases, including azathioprine/6-MP, modified TPMT activity, but the magnitude of this effect was very small and the differences found are probably irrelevant from the clinical point of view.

Thiopurine methyltransferase (TPMT) activity and adverse effects of azathioprine in inflammatory bowel disease: long-term follow-up study of 394 patients.

AIM: To prospectively evaluate whether a relationship between thiopurine methyltransferase (TPMT) activity and incidence of adverse effects (especially myelotoxicity) exists, in a long-term follow-up study of a large group of patients with inflammatory bowel disease treated with azathioprine. METHODS: TPMT activity in red blood cells (RBC) was measured by a radiochemical method in 394 consecutive patients with Crohn's disease (238) or ulcerative colitis (156) starting treatment with azathioprine. The relationship among several variables and TPMT values was assessed, and the correlation between such levels and the incidence of adverse effects was evaluated. RESULTS: Mean TPMT value was 18.6 +/- 4 U/mL RBCs (range 9.4-33.7). No patient had low levels (<5), 7.1% had intermediate levels (5-13.7), and 92.9% had high levels (>13.8). Differences (P < 0.001) were demonstrated in TPMT activity depending on the type of inflammatory bowel disease, but not on the remaining variables (including treatment with 5-aminosalycilates). Adverse effects were reported in 74 patients (18.8%), the most frequent being gastrointestinal intolerance (9.1%) and myelotoxicity (4.3%). No patient having adverse effects had low TPMT levels. However, mean TPMT activity was lower in those with adverse effects (16.6 +/- 3 vs 19.1 +/- 4 U/mL, P < 0.001). Moreover, the probability of suffering myelotoxicity in the high TPMT group was only 3.5%, compared with 14.3% in the TPMT intermediate group (95% CI = 1.37-14.9; OR = 4.5). CONCLUSIONS: The strategy of determining TPMT activity in all patients prior to initiating treatment with azathioprine could help to minimize the risk of myelotoxicity, as patients with intermediate TPMT activity had fourfold more risk than high TPMT activity patients.

Choice of azathioprine or 6-mercaptopurine dose based on thiopurine methyltransferase (TPMT) activity to avoid myelosuppression. A prospective study.

BACKGROUND/AIMS: To prospectively evaluate whether, in patients with inflammatory bowel disease, the choice of azathioprine (AZA) or 6-mercaptopurine (6-MP) dose based on thiopurine methyltransferase (TPMT) activity prevents myelotoxicity. METHODOLOGY: TPMT activity in red blood cells was measured in 99 patients with Crohn's disease and 32 with ulcerative colitis prior to initiating AZA/6-MP treatment. AZA/6-MP dose was chosen based on TPMT activity, which was again determined one month after starting therapy. Incidence of adverse effects was evaluated for at least 6 months of follow-up. RESULTS: Mean basal TPMT value was 21.6 +/- 5 U/mL. No patient had low levels (< 5 U/mL), 6.9% had intermediate levels (5-13.7 U/mL), and 93.1% had high levels (> 13.8 U/mL). In patients with Crohn's disease, mean TPMT activity significantly decreased after AZA/6-MP therapy, while in patients with ulcerative colitis this activity did not change. Among the 4 patients having myelotoxicity, one had intermediate basal TPMT levels, and 3 even had high levels, but no patient had low levels. CONCLUSIONS: In this prospective study we could not confirm that the choice of AZA/6-MP dose based on TPMT activity prevents myelotoxicity in patients with inflammatory bowel disease. Routine analytical controls should be performed in these patients independently of TPMT activity.

Azathioprine acts upon rat hepatocyte mitochondria and stress-activated protein kinases leading to necrosis: protective role of N-acetyl-L-cysteine.

Azathioprine is an immunosuppressant drug widely used. Our purpose was to 1) determine whether its associated hepatotoxicity could be attributable to the induction of a necrotic or apoptotic effect in hepatocytes, and 2) elucidate the mechanism involved. To evaluate cellular responses to azathioprine, we used primary culture of isolated rat hepatocytes. Cell metabolic activity, reduced glutathione, cell proliferation, and lactate dehydrogenase release were assessed. Mitochondria were isolated from rat livers, and swelling and oxygen consumption were measured. Mitogen-activated protein kinase pathways and proteins implicated in cell death were analyzed. Azathioprine decreased the viability of hepatocytes and induced the following events: intracellular reduced glutathione (GSH) depletion, metabolic activity reduction, and lactate dehydrogenase release. However, the cell death was not accompanied by DNA laddering, procaspase-3 cleavage, and cytochrome c release. The negative effects of azathioprine on the viability of hepatocytes were prevented by cotreatment with N-acetyl-L-cysteine. In contrast, 6-mercaptopurine showed no effects on GSH content and metabolic activity. Azathioprine effect on hepatocytes was associated with swelling and increased oxygen consumption of intact isolated rat liver mitochondria. Both effects were cyclosporine A-sensitive, suggesting an involvement of the mitochondrial permeability transition pore in the response to azathioprine. In addition, the drug's effects on hepatocyte viability were partially abrogated by c-Jun N-terminal kinase and p38 kinase inhibitors. In conclusion, our findings suggest that azathioprine effects correlate to mitochondrial dysfunction and activation of stress-activated protein kinase pathways leading to necrotic cell death. These negative effects of the drug could be prevented by coincubation with N-acetyl-L-cysteine.

[Thiopurine methyltransferase activity and myelosuppression in inflammatory bowel disease patients treated with azathioprine and 6-mercaptopurine]. / Actividad de la tiopurina metiltransferasa y mielotoxicidad debida a azatioprina y 6-mercaptopurina en pacientes con enfermedad inflamatoria del intestino.

BACKGROUND AND OBJECTIVE: We aimed at assessing whether there exists a relationship between thiopurine methyltransferase (TPMT) activity and the incidence of adverse events, especially myelotoxicity, in patients with inflammatory bowel disease treated with azathioprine (AZA) or 6-mercaptopurine (6-MP). PATIENTS AND METHOD: By means of a radiochemical method, we determined the TPMT activity in erythrocytes of patients with inflammatory bowel disease who had received previously or at the time of the study AZA or 6-MP (n = 97). A group of 37 patients who had never been treated with these drugs was included. We studied the relationship between several variables and TPMT values as well as their correlation with adverse events. RESULTS: Mean (SD) TPMT value was 20.8 (5) U/ml erythrocytes (from 7.8 to 32.7). There was no patient with low TPMT levels (< 5); 9% patients had intermediate levels (from 5 to 13.7 U/ml), while 91% displayed high levels (>= 13.8 U/ml). There were no differences when comparing TPMT values according to several variables such as age, gender, tobacco consumption, weight, type of inflammatory bowel disease, and treatment with 5-aminosalicylates, steroids or AZA/6-MP. Side effects were seen in 13 out of 97 (13%) patients administered AZA/6-MP. None patient with side effects exhibited low TPMT levels (< 5 U/ml), nor even intermediate levels (5-13.7 U/ml). There were no differences when comparing mean TPMT values in patients with side effects and in those without side effects. CONCLUSIONS: In this study, the usefulness of the determination of the TPMT activity to identify patients with inflammatory bowel disease at risk of myelotoxicity due to AZA or 6-MP has not been confirmed. Therefore, even when the TPMT enzymatic activity is normal, it is necessary to continue performing the periodic laboratory analysis.