Combination Therapy With Infliximab and Azathioprine Improves Infliximab Pharmacokinetic Features and Efficacy: A Post Hoc Analysis.

BACKGROUND & AIMS: Among immunosuppressive- and biologic-naïve patients with moderately-to-severely active Crohn's disease (CD), a higher proportion of those treated with the combination of infliximab and azathioprine achieved corticosteroid-free remission at week 26 (CSFR26) than those given infliximab monotherapy; patients given the combination therapy also had higher serum concentrations of infliximab. Enhanced benefit of combination therapy may occur through synergistic modes of action or the influence of azathioprine on infliximab pharmacokinetics. METHODS: We analyzed data from 206 patients from whom week 30 serum samples were available: 97 received infliximab monotherapy (5 mg/kg, n = 97) and 109 received combination therapy (2.5 mg/kg/day; n = 109). Proportions of patients achieving CSFR26 and mucosal healing (absence of ulcers) at week 26 were calculated for each quartile of serum concentrations of infliximab, and exposure-response relationships were compared. RESULTS: Within quartiles of serum concentrations of infliximab, CSFR26 did not differ significantly between patients who received combination therapy vs monotherapy. However, among patients in the lowest quartile of serum concentration of infliximab, twice as many patients who received infliximab monotherapy achieved CSFR26 vs combination therapy. Anti-drug antibodies were detected only in the lowest quartile of serum concentrations of infliximab-in 35.9% of patients given monotherapy and 8.3% of patients given combination therapy. CONCLUSION: Among patients with CD and similar serum concentrations of infliximab, combination therapy with azathioprine was not significantly more effective than infliximab monotherapy. Combination therapy with azathioprine appears to improve efficacy by increasing pharmacokinetic features of infliximab. ClinicalTrials.gov, NCT00094458.

The relationship between infliximab concentrations, antibodies to infliximab and disease activity in Crohn's disease.

OBJECTIVE: Although low infliximab trough concentrations and antibodies to infliximab (ATI) are associated with poor outcomes in patients with Crohn's disease (CD), the clinical relevance of ATI in patients with adequate infliximab concentrations is uncertain. We evaluated this question using an assay sensitive for identification of ATI in the presence of infliximab. DESIGN: In an observational study, 1487 trough serum samples from 483 patients with CD who participated in four clinical studies of maintenance infliximab therapy were analysed using a fluid phase mobility shift assay. Infliximab and ATI concentrations most discriminant for remission, defined as a C-reactive protein concentration of ≤ 5 mg/L, were determined by receiver operating characteristic curves. A multivariable regression model evaluated these factors as independent predictors of remission. RESULTS: Based upon analysis of 1487 samples, 77.1% of patients had detectable and 22.9% had undetectable infliximab concentrations, of which 9.5% and 71.8%, respectively, were positive for ATI. An infliximab concentration of > 2.79 µg/mL (area under the curve (AUC) = 0.681; 95% CI 0.632 to 0.731) and ATI concentration of < 3.15 U/mL (AUC = 0.632; 95% CI 0.589 to 0.676) were associated with remission. Multivariable analysis showed that concentrations of both infliximab trough (OR 1.8; 95% CI 1.3 to 2.5; p < 0.001) and ATI (OR 0.57; 95% CI 0.39 to 0.81; p = 0.002) were independent predictors of remission. CONCLUSIONS: The development of ATI increases the probability of active disease even at low concentrations and in the presence of a therapeutic concentration of drug during infliximab maintenance therapy. Evaluation of strategies to prevent ATI formation, including therapeutic drug monitoring with selective infliximab dose intensification, is needed.

Adalimumab induces deep remission in patients with Crohn's disease.

BACKGROUND & AIMS: Patients with moderate to severe ileocolonic Crohn's disease (CD) who received adalimumab induction and maintenance therapy had greater rates of mucosal healing than patients who received placebo after adalimumab induction therapy in a 52-week trial (EXTend the Safety and Efficacy of Adalimumab Through ENDoscopic Healing). We investigated whether this treatment also induced deep remission-a composite clinical and endoscopic end point. METHODS: Rates of deep remission, defined as the absence of mucosal ulceration and CD Activity Index scores less than 150, were compared between patients given continuous adalimumab and those given only induction therapy followed by placebo. We assessed the relationships between deep remission and other outcomes among patients who received adalimumab. The outcomes of patients with deep remission were compared with those of patients with only the absence of mucosal ulceration or only clinical remission. RESULTS: Rates of deep remission were 16% in patients given adalimumab vs 10% in those given placebo (P = .34) at week 12, and 19% vs 0% (P < .001) at week 52. Rates of deep remission were greatest among patients who received adalimumab and had CD for 2 years or less (33% at weeks 12 and 52). At week 52, patients who achieved deep remission at week 12 required significantly fewer adalimumab treatment adjustments, hospitalizations, and CD-related surgeries; had significantly less activity impairment; and had better quality of life and physical function compared with patients not achieving deep remission. Deep remission generally was associated with better outcomes than only an absence of mucosal ulceration; outcomes of patients with deep remission vs only clinical remission were similar. Deep remission was associated with estimated total cost savings of $10,360 (from weeks 12 through 52) compared with lack of deep remission. CONCLUSIONS: In an exploratory study of patients with moderate to severe ileocolonic CD who received adalimumab induction and maintenance therapy, patients achieving deep remission appeared to have better 1-year outcomes than those not achieving deep remission. These findings should be validated in large, prospective trials. ClinicalTrials.gov number: NCT00348283.

Validation of endoscopic activity scores in patients with Crohn's disease based on a post hoc analysis of data from SONIC.

BACKGROUND & AIMS: Mucosal healing might alter midterm and long-term outcomes of patients with Crohn's disease (CD) and has become an important end point in clinical trials. However, the minimal degree of mucosal improvement (endoscopic response) required to alter midterm outcomes is not known. We aimed to determine the best definition of endoscopic response by evaluating data on the Simple Endoscopic Score for Crohn's Disease (SES-CD) and the Crohn's Disease Endoscopic Index of Severity (CDEIS) from the Study of Biologic and Immunomodulator Naive Patients in Crohn's Disease (SONIC trial). METHODS: We analyzed data from 172 patients who participated in the SONIC trial, were found to have endoscopic lesions at baseline, and underwent a second endoscopic examination at week 26 of treatment with infliximab, azathioprine, or both. Mucosal healing was defined as absence of ulcers. A central reader calculated SES-CD and CDEIS results. Different cutoff values were set for endoscopic response based on the SES-CD or CDEIS. The diagnostic ability of these different cutoff values was evaluated using receiver operating characteristic (ROC) curves, positive likelihood ratios (PLR), and negative likelihood ratios (NLR). Corticosteroid-free clinical remission (CFREM) at week 50 was used as a binary classifier. RESULTS: Based on analyses of ROC curves, PLR, and NLR, endoscopic response was defined as a decrease from baseline in SES-CD of at least 50%. At week 26, mucosal healing and endoscopic response were achieved in 48% and 65% of patients, respectively. Mucosal healing at week 26 was associated with CFREM at week 50, with 56% sensitivity, 65% specificity, a PLR of 1.60, and an NLR of 0.67. Endoscopic response at week 26 was associated with CFREM at week 50, with 74% sensitivity, 48% specificity, a PLR of 1.42, and an NLR of 0.54. Endoscopic response, defined as a decrease from baseline in CDEIS of at least 50%, yielded similar results. CONCLUSIONS: In patients with CD, mucosal healing and endoscopic response (defined as a decrease from baseline in SES-CD or CDEIS of at least 50%) at week 26 of treatment identified those most likely to be in CFREM at week 50. The ability of the proposed endoscopic response cutoff value to predict midterm CFREM should be validated in an independent, prospective cohort. Its correlation with changes in long-term disease progression still needs to be demonstration. ClinicalTrials.gov, Number: NCT00094458.

A randomised phase I study of etrolizumab (rhuMAb ß7) in moderate to severe ulcerative colitis.

OBJECTIVE: Etrolizumab (rhuMAb ß7, anti-ß7, PRO145223) is a humanised monoclonal antibody targeting the ß7 subunit of the heterodimeric integrins α4ß7 and αEß7, which are implicated in leucocyte migration and retention in ulcerative colitis (UC). This randomised phase I study evaluated the safety and pharmacology of etrolizumab in patients with moderate to severe UC. DESIGN: In the single ascending dose (SAD) stage, etrolizumab (0.3, 1.0, 3.0, 10 mg/kg intravenous, 3.0 mg/kg subcutaneous (SC) or placebo) was administered 4:1 (n=25) in each cohort. In the multiple dose (MD) stage, new patients received monthly etrolizumab (0.5 mg/kg SC (n=4), 1.5 mg/kg SC (n=5), 3.0 mg/kg SC (n=4), 4.0 mg/kg intravenous (n=5)) or placebo (n=5). The pharmacokinetics was studied and Mayo Clinic Score evaluated at baseline, day 29 (SAD), and days 43 and 71 (MD). RESULTS: In the SAD stage, there were no dose limiting toxicities, infusion or injection site reactions. Two impaired wound healing serious adverse events occurred in two patients receiving etrolizumab. In the MD stage, there were no dose limiting toxicities, and no infusion or injection site reactions. Headache was the most common adverse event, occurring more often in etrolizumab patients. Antietrolizumab antibodies were detected in two subjects. The duration of ß7 receptor full occupancy was dose related. A clinical response was observed in 12/18 patients, and clinical remission in 3/18 patients treated with etrolizumab in the MD stage, compared with 4/5 and 1/5 placebo patients, respectively. CONCLUSION: Etrolizumab is well tolerated in moderate to severe UC. Further investigation is warranted.

Levels of C-reactive protein are associated with response to infliximab therapy in patients with Crohn's disease.

BACKGROUND & AIMS: Infliximab is an antibody against tumor necrosis factor-α that is used to treat patients with moderate to severe Crohn's disease (CD). C-reactive protein (CRP) is a marker used to identify and follow individuals with CD. We analyzed changes in levels of CRP in a large cohort of patients with CD undergoing treatment with infliximab. METHODS: Serial levels of CRP were analyzed in 718 CD patients. Blood was collected before each infusion; a total of 8845 CRP levels were available for analysis. The correlations between CRP levels and need for dose adjustment, outcomes, and mucosal healing (based on endoscopic analysis of 253 patients) were evaluated. Therapy adjustment was considered successful if therapy continued without need for change. Subgroup analysis was performed by using data from 268 patients who received 8 weeks of maintenance therapy. RESULTS: More patients with high baseline levels of CRP responded to infliximab than patients with normal levels (90.8% vs 82.6%; P = .014). Early normalization of CRP levels correlated with sustained long-term response (P < .001). CRP levels remained significantly higher among patients who lost their response to infliximab, compared with those with a sustained response (P = .001). At time of loss of response, CRP levels were significantly increased (median, 11.2 mg/L) and did not return to baseline levels (median, 18.2 mg/L; P = .039). CRP correlated with mucosal healing (P = .033). CONCLUSIONS: CRP is a good marker of disease activity in patients treated with infliximab. Increased levels of CRP indicate mucosal inflammation and a likelihood of clinical relapse.

From aphthous ulcer to full-blown Crohn's disease.

At onset, Crohn's disease (CD) is characterized by transmural inflammation with mucosal ulcerations. In its earliest phase the lesions are mainly aphthous ulcers. The ulcers then become larger, a nodular pattern develops and penetration of the deep ulcers leads to fistulas and collagen deposition to fibrotic strictures. The best model to study the earliest lesions in CD is the postoperative recurrence situation where these early lesions recur within weeks to months after surgery. CD recurrence is triggered by the fecal contents of the gut since temporary diversion prevents the recurrence of bowel inflammation. With the development of newer techniques, such as microarray analysis of total mucosal gene expression and molecular analysis of gut content and mucosal microbiome, this model will allow to shed light on the earliest pathogenic features of CD.

Effects of adalimumab therapy on incidence of hospitalization and surgery in Crohn's disease: results from the CHARM study.

BACKGROUND & AIMS: We determined the effects of adalimumab maintenance treatment on the risks of hospitalization and surgery in Crohn's disease (CD). METHODS: A total of 778 patients with CD were randomized to placebo, adalimumab 40 mg every other week or adalimumab 40 mg weekly, all after an 80-mg/40-mg adalimumab induction regimen. All-cause and CD-related hospitalizations and major CD-related surgeries were compared between the placebo and adalimumab groups (every other week, weekly, and both combined) using Kaplan-Meier analysis and Cox proportional hazard models. RESULTS: Both 3- and 12-month hospitalization risks were significantly lower for patients who received adalimumab. Hazard ratios for all-cause hospitalization were 0.45, 0.36, and 0.40 for the adalimumab every other week, weekly, and combined groups, respectively (all P < .01 vs placebo). Hazard ratios for CD-related hospitalization were 0.50, 0.34, and 0.42, respectively (all P < .05). Cox model estimates demonstrated adalimumab every other week and weekly maintenance therapies were associated with 52% and 60% relative reductions in 12-month, all-cause hospitalization risk, and 48% and 64% reductions in 12-month risk of CD-related hospitalization. The combined adalimumab group was associated with 56% reductions in both all-cause and CD-related hospitalization risks. Fewer CD-related surgeries occurred in the adalimumab every other week, weekly, and combined groups compared with placebo (0.4, 0.8, and 0.6 vs 3.8 per 100 patients; all P < .05). CONCLUSIONS: Patients with moderate-to-severe CD treated with adalimumab had lower 1-year risks of hospitalization and surgery than placebo patients.

Long-Term Outcome of Patients with Ulcerative Colitis and Primary Non-response to Infliximab.

BACKGROUND AND AIMS: We studied the long-term outcome of patients with ulcerative colitis [UC] and primary non response [PNR] to infliximab and searched for predictors of colectomy in these patients. METHODS: This retrospective, multi-centre study included UC patients from three European referral centres, with PNR to infliximab defined as a lack of clinical improvement after the induction therapy, leading to drug discontinuation. Relapse, for patients who continued on biologicals after PNR to infliximab, was defined as drug discontinuation for PNR, loss of response, or serious adverse event. Serum infliximab concentrations at Weeks 2 and 6 were evaluated using an enzyme-linked immunosorbent assay [ELISA] developed in house. RESULTS: The study population consisted of 99 anti-tumour necrosis factor [TNF]-naïve patients with UC and PNR to infliximab. At the end of follow-up (median: 3.2 [interquartile range 1-6.3] years), 55 [55.6%] of these patients underwent colectomy. Multiple Cox regression analysis identified acute severe UC (hazard ratio [HR]: 24; 95% confidence interval [CI]: 2.5-231; p = 0.006], baseline C-reactive protein [CRP] > 5mg/l [HR: 11; 95% CI: 2.1-58.8; p = 0.005], baseline albumin < 40g/l [HR: 9.5; 95% CI: 1.3-71.4; p = 0.026], and infliximab concentration at Week 2 < 16.5 µg/ml [HR: 5.6; 95% CI: 1.1-27.8; p = 0.034] as independent predictors of colectomy. Regarding patients who continued on biologicals after PNR to infliximab, there was a marginally higher cumulative probability for relapse in patients switching to another anti-TNF agent compared with those swapping to vedolizumab [p logrank = 0.08]. CONCLUSIONS: About half of UC patients with PNR to infliximab will undergo colectomy. Patients with severe inflammation and low serum infliximab concetrations during the induction phase are at greatest risk.

Concordance in Anti-OmpC and Anti-I2 Indicate the Influence of Genetic Predisposition: Results of a European Study of Twins with Crohn's Disease.

BACKGROUND AND AIMS: An adaptive immunological response to microbial antigens has been observed in Crohn's disease (CD). Intriguingly, this serological response precedes the diagnosis in some patients and has also been observed in healthy relatives. We aimed to determine whether genetic factors are implicated in this response in a CD twin cohort. METHODS: In total, 82 twin pairs (Leuven n = 13, Maastricht n = 8, Örebro n = 61) took part: 81 pairs with CD (concordant monozygotic n = 16, discordant monozygotic n = 22, concordant dizygotic n = 3, discordant dizygotic n = 40) and 1 monozygotic pair with both CD and ulcerative colitis. Serology for Pseudomonas fluorescens-related protein (anti-I2), Escherichia coli outer membrane porin C (anti-OmpC), CBir1flagellin (anti-CBir1) and antibodies to oligomannan (anti-Saccharomyces cerevisiae antibody [ASCA]) was determined by standardized enzyme-linked immunoassay. RESULTS: All markers were more often present in CD twins than in their healthy twin siblings. Using the intraclass correlation coefficient (ICC), agreements in concentrations of anti-OmpC and anti-I2 were observed in discordant monozygotic but not in discordant dizygotic twin pairs with CD (anti-OmpC, ICC 0.80 and -0.02, respectively) and (anti-I2, ICC 0.56 and 0.05, respectively). In contrast, no agreements were found in anti-CBir, immunoglobulin (Ig) G ASCA and ASCA IgA. CONCLUSIONS: We show that anti-I2 and anti-CBir1 statuses have specificity for CD and confirm previous reported specificities for anti-OmpC and ASCA. Based on quantitative analyses and observed ICCs, genetics seems to predispose to the anti-OmpC and anti-I2 response but less to ASCA and anti-CBir1 responses.

An historical overview of the treatment of Crohn's disease: why do we need biological therapies?

Crohn's disease is a disabling inflammatory bowel disease that may involve any part of the gastrointestinal tract. The disease decreases quality of life and leads to complications including stenoses, abscesses, and fistulae necessitating repeated surgeries and bowel resections. Until the late 1990s, standard therapies included mainly glucocorticosteroids, 5-aminosalicylic acid (5-ASA), antibiotics, and to a lesser extent, immunosuppression with azathioprine (AZA)/6-mercaptopurine (6-MP) or methotrexate. These therapies, especially glucocorticosteroids, mainly controlled symptoms without modifying the long-term disease course. Glucocorticosteroids also do not induce sustained mucosal healing. The lack of healing capacity mirrors the absent long-term efficacy of these drugs. Moreover, long-term use of glucocorticosteroids is associated with serious and sometimes irreversible side effects. AZA/6-MP are effective disease-modifying therapies that have been used in patients who are refractory to or relapse after steroids. Unfortunately, these agents have yet to have an established optimal benefit due to variations in genetically determined metabolism. With the advent of biologicals, new treatment aims have been advanced, including induction of remission with bowel healing both short term and long term, as well as reduction in the rate of complications, surgeries, and mortality.

Drug safety evaluation of certolizumab pegol.

INTRODUCTION: The introduction of antibodies directed against tumor necrosis factor (anti-TNF) has dramatically changed our concept of treating both patients with Crohn's disease (CD) and patients with rheumatoid arthritis (RA). Subcutaneous injections with certolizumab pegol (CZP) have been shown efficacious for both CD and RA. In this review, the authors focus on the safety of CZP among other anti-TNF agents. AREAS COVERED: A literature search till June 2013 was performed to identify all trials studying CZP in patients with CD and RA. In addition, abstracts of major congresses were assessed. The authors first focused on the mechanism of action of CZP, and evaluated the efficacy of this drug in both CD and RA. Next, they explored the available safety data on CZP, including infection and malignancy risk, injection site reactions, the development of antibodies against CZP, as well as its use during pregnancy. EXPERT OPINION: Based on the provided literature, CZP seems to have a similar safety profile to other anti-TNF agents. However, in young females considering pregnancy, CZP may be advocated over other anti-TNF agents as it does not actively cross the placenta.

Extracorporeal photopheresis (ECP) in patients with steroid-dependent Crohn's disease: an open-label, multicenter, prospective trial.

BACKGROUND: Extracorporeal photopheresis (ECP) involves ex vivo leukocyte treatment with methoxsalen and UVA light to generate a tolerogenic response. A previous trial demonstrated that ECP permits corticosteroid withdrawal in steroid-dependent Crohn's disease (CD) patients who were in clinical remission. We studied the effect of ECP on steroid withdrawal in steroid-dependent CD. METHODS: Patients with CD for ≥ 6 months, in remission at baseline while on steroids, but who had failed at ≥ 1 steroid withdrawal were included. Patients received two ECP treatments every 2 weeks for the 24-week steroid tapering period and underwent steroid-tapering. Patients completing steroid tapering could receive maintenance ECP (two treatments/week) every month for 24 weeks. RESULTS: Thirty-one patients (Crohn's Disease Activity Index [CDAI] score 91; Inflammatory Bowel Disease Questionnaire [IBDQ] 172.5) were enrolled (baseline corticosteroid dose, 20 mg/day); 65% were refractory to/intolerant of anti-tumor necrosis factor (TNF) agents or immunosuppressants. After 24 weeks of ECP, 7 of 31 (22.6%) patients discontinued steroids while maintaining a CDAI of <150. At week 24, the steroid dose for the remaining patients on corticosteroids was 10 mg (P < 0.003 vs. baseline) with a CDAI of 110 and an IBDQ of 179. Following maintenance treatment, three patients remained in steroid-free remission. The 10 patients in the study and receiving ECP at week 48 had a steroid dose of 3.5 mg with a CDAI of 40 and an IBDQ of 188. CONCLUSIONS: ECP permitted discontinuation or reduction of steroids in a population of refractory steroid-dependent CD patients. ECP may be useful in permitting steroid withdrawal in selected steroid-dependent CD patients. Ideally, these results need to be confirmed in a "sham-controlled clinical trial.

Endpoints for clinical trials evaluating disease modification and structural damage in adults with Crohn's disease.

The management of Crohn's disease is rapidly changing. The advent of potent immunomodulatory and biologic therapies has led to more demanding endpoints for clinical trials than only clinical response and remission. Complete withdrawal of corticosteroids, healing of endoscopically visible lesions, and prevention of structural damage are only a few new endpoints that are finding their way into the clinical trials of today and those that are being developed for the future. Given the importance of selecting the most appropriate and relevant endpoints, the International Organization for Inflammatory Bowel Diseases (IOIBD) decided to develop guidelines that could be used by individual researchers, the pharmaceutical industry, and the regulatory bodies. The current document is to be read as a "position paper," which is the result of several years of discussion and consensus finding that was finally approved by the entire membership of the group. The proposed instruments will need further validation and standardization to demonstrate that they are reliable in stable disease and responsive to change, and to determine the cutoff points for response and remission.

Natalizumab for the treatment of active Crohn's disease: results of the ENCORE Trial.

BACKGROUND & AIMS: A randomized placebo-controlled trial evaluated the efficacy of natalizumab induction therapy in patients with Crohn's disease. METHODS: Patients (N = 509) with moderately to severely active Crohn's disease and active inflammation characterized by elevated C-reactive protein concentrations were randomized (1:1) to receive natalizumab 300 mg or placebo intravenously at Weeks 0, 4, and 8. The primary end point was induction of response (> or =70-point decrease from baseline in the Crohn's Disease Activity Index score at Week 8 sustained through Week 12). Additional efficacy end points included the proportion of patients with sustained remission (Crohn's Disease Activity Index score <150 points) and response or remission over time. RESULTS: Response at Week 8 sustained through Week 12 occurred in 48% of natalizumab-treated patients and 32% of patients receiving placebo (P < .001). Sustained remission occurred in 26% of natalizumab-treated patients and 16% of patients receiving placebo (P = .002). Week 4 response rates were 51% for natalizumab and 37% for placebo (P = .001). Responses remained significantly higher at subsequent assessments (P < .001) in natalizumab-treated patients. Natalizumab-treated patients also had significantly higher remission rates at Weeks 4, 8, and 12 (P < or = .009). The frequency and types of adverse events were similar between treatment groups. CONCLUSIONS: Natalizumab induced response and remission at Week 8 that was sustained through Week 12. Response and remission rates for natalizumab were superior to those for placebo at Weeks 4, 8, and 12, demonstrating the early and sustained efficacy of natalizumab as induction therapy in patients with elevated C-reactive protein and active Crohn's disease. Natalizumab was well tolerated in this study.