A retrospective comparison of infliximab versus adalimumab as induction and maintenance therapy for Crohn disease

BACKGROUND

In Australia, infliximab (IFX) and adalimumab (ADA) are available for the treatment of moderate-severe Crohn disease (CD) refractory to conventional therapies, with minimal local data comparing their efficacy.

AIM

The aim of this study was to compare clinical and biochemical outcomes at 3 and 12 months between patients receiving induction and maintenance therapy with IFX versus ADA.

METHODS

Retrospective single-centre audit of all patients commenced on IFX or ADA as their first anti-tumour necrosis factor agent between July 2007 and May 2012. Clinical and biochemical parameters were compared pre-commencement, 3 and 12 months post-commencement.

RESULTS

A total of 81 patients was included in the study; 63 IFX-treated and 18 ADA-treated. Significant Crohn disease activity index (CDAI) reductions were noted within both groups at 3 months (P < 0.001) and 12 months (P < 0.001). Similarly, significant reductions were noted in steroid doses within groups at 3 months (P < 0.05) and 12 months (P < 0.05), with notable reductions in C-reactive protein (CRP) at 3 months within groups (P < 0.05). Adverse events occurred in 14.3% of IFX and 11.1% of ADA patients. Comparing IFX with ADA, no difference was shown between groups in CDAI reductions at 3 months (P = 0.94) and 12 months (P = 0.95), steroid dosing at 3 months (P = 0.23) and 12 months (P = 0.81), and CRP reduction at 3 months (P = 0.33) and 12 months (P = 0.62). Fistula-related admissions were significantly reduced in IFX patients (100% reduction post-IFX vs 66.7% post-ADA) (P = 0.01).

CONCLUSION

Clinical and biochemical outcomes were similar in patients treated with IFX or ADA as induction and maintenance therapy for CD. However, significant reductions were noted in admissions relating to fistulising disease in IFX patients.

Anti-MAdCAM antibody (PF-00547659) for ulcerative colitis (TURANDOT): a phase 2, randomised, double-blind, placebo-controlled trial

BACKGROUND

PF-00547659 is a fully human monoclonal antibody that binds to human mucosal addressin cell adhesion molecule-1 (MAdCAM-1) to selectively reduce lymphocyte homing to the intestinal tract. We aimed to assess the efficacy and safety of PF-00547659 in patients with moderate to severe ulcerative colitis.

METHODS

This phase 2, randomised, double-blind, placebo-controlled clinical trial recruited patients aged 18-65 years from 105 centres in 21 countries, with a history (≥3 months) of active ulcerative colitis extending more than 15 cm beyond the anal verge (with a total Mayo score ≥6 and a Mayo endoscopic subscore ≥2) who had failed or were intolerant to at least one conventional therapy. Patients were stratified by previous anti-TNFα treatment, and randomly assigned by a computer-generated randomisation schedule to receive a subcutaneous injection of 7·5 mg, 22·5 mg, 75 mg, or 225 mg PF-00547659 or placebo at baseline, then every 4 weeks. Patients, investigators, and sponsors were blinded to the treatment. The primary endpoint was the proportion of patients achieving remission (total Mayo score ≤2 with no individual subscore >1 and rectal bleeding subscore ≤1) at week 12. The efficacy analysis included all patients who received at least one dose of the randomised treatment; the safety analysis was done according to treatment received. All p values were one-sided and multiplicity-adjusted. This study is registered with ClinicalTrials.gov, number NCT01620255.

FINDINGS

Between Nov 2, 2012, and Feb 4, 2016, we screened 587 patients; 357 were eligible and randomly assigned to receive placebo (n=73) or PF-00547659 at doses of 7·5 mg (n=71), 22·5 mg (n=72), 75 mg (n=71), or 225 mg (n=70). Remission rates at week 12 were significantly greater in three of four active-treatment groups than in the placebo group (2·7% [two of 73]): 7·5 mg (11·3% [eight of 71]), 22·5 mg (16·7% [12 of 72]), 75 mg (15·5% [11 of 71]), and 225 mg (5·7% [four of 70]). These rates corresponded to a stratum-adjusted (anti-TNFα-naive and anti-TNFα-experienced) risk difference versus placebo of 8·0% for 7·5 mg (90% CI 1·9 to 14, p=0·0425), 12·8% for 22·5 mg (5·6 to 19·9, p=0·0099), 11·8% for 75 mg (4·8 to 18·8, p=0·0119), and 2·6% for 225 mg (-1·2 to 6·4, p=0·1803). Four of 73 (5·5%) patients had a serious adverse event in the placebo group, ten of 71 (14·1%) in the 7·5 mg group, one of 70 (1·4%) in the 22·5 mg group, three of 73 (4·1%) in the 75 mg group, and three of 70 (4·3%) in the 225 mg group. No safety signal was observed for the study drug.

INTERPRETATION

PF-00547659 was safe and well tolerated in this patient population, and better than placebo for induction of remission in patients with moderate to severe ulcerative colitis. The greatest clinical effects were observed with the 22·5 mg and 75 mg doses.

FUNDING

Pfizer.

Serologic antibodies in relation to outcome in postoperative Crohn's disease

BACKGROUND AND AIM

Disease recurs frequently after Crohn's disease resection. The role of serological antimicrobial antibodies in predicting recurrence or as a marker of recurrence has not been well defined.

METHODS

A total of 169 patients (523 samples) were prospectively studied, with testing peri-operatively, and 6, 12 and 18 months postoperatively. Colonoscopy was performed at 18 months postoperatively. Serologic antibody presence (perinuclear anti-neutrophil cytoplasmic antibody [pANCA], anti-Saccharomyces cerevisiae antibodies [ASCA] IgA/IgG, anti-OmpC, anti-CBir1, anti-A4-Fla2, anti-Fla-X) and titer were tested. Quartile sum score (range 6-24), logistic regression analysis, and correlation with phenotype, smoking status, and endoscopic outcome were assessed.

RESULTS

Patients with ≥ 2 previous resections were more likely to be anti-OmpC positive (94% vs 55%, ≥ 2 vs < 2, P = 0.001). Recurrence at 18 months was associated with anti-Fla-X positivity at baseline (49% vs 29%; positive vs negative, P = 0.033) and 12 months (52% vs 31%, P = 0.04). Patients positive (n = 28) for all four antibacterial antibodies (anti-CBir1, anti-OmpC, anti-A4-Fla2, and anti-Fla-X) at baseline were more likely to experience recurrence at 18 months than patients negative (n = 32) for all four antibodies (82% vs 18%, P = 0.034; odds ratio 6.4, 95% confidence interval 1.16-34.9). The baseline quartile sum score for all six antimicrobial antibodies was higher in patients with severe recurrence (Rutgeert's i3-i4) at 18 months, adjusted for clinical risk factors (odds ratio 1.16, 95% confidence interval 1.01-1.34, P = 0.039). Smoking affected antibody status.

CONCLUSIONS

Anti-Fla-X and presence of all anti-bacterial antibodies identifies patients at higher risk of early postoperative Crohn's disease recurrence. Serologic screening pre-operatively may help identify patients at increased risk of recurrence.

Is there a role for thioguanine therapy in IBD in 2017 and beyond?

Conventional thiopurines are effective for the maintenance of remission of Crohn's disease and ulcerative colitis, however, up to half of patients are intolerant or unresponsive to these medications. Thioguanine is an alternative thiopurine that has shown efficacy in inflammatory bowel disease, and is particularly useful to circumvent certain side effects associated with conventional thiopurines, for example, pancreatitis. Its association with nodular regenerative hyperplasia of the liver has hindered its widespread use. Areas covered: We aim to outline the rational use of thioguanine, including safety monitoring, with particular regard to hepatotoxicity. A literature search was performed: PubMed was searched for full papers and abstracts published in English since January 2000 using the following terms, alone and in combination: 'azathioprine', 'thiopurine', 'Crohn's disease', 'inflammatory bowel disease', 'nodular regenerative hyperplasia', 'mercaptopurine', 'thioguanine', 'ulcerative colitis'. Further relevant papers were identified from the reference lists of selected papers. Expert commentary: Despite optimisation strategies such as metabolite measurements and the use of allopurinol, a significant proportion of patients will remain intolerant to thiopurines, especially those with allergic reactions, including pancreatitis. For this subgroup of patients we suggest that low dose thioguanine is an alternative to other therapies that are either parenteral or expensive.

Intra-patient variability in adalimumab drug levels within and between cycles in Crohn's disease

BACKGROUND

Whether therapeutic drug monitoring for adalimumab needs to be performed at trough has not been defined.

AIM

To determine intra-patient adalimumab drug-level variation and to identify modulating patient and disease factors.

METHODS

In this prospective observational study, adult patients with Crohn's disease established on maintenance adalimumab had drug levels measured repeatedly according to pre-defined schedules (visit 1: day 4-6, visit 2: day 7-9, trough: day 13-14) across two consecutive fortnightly cycles. Disease activity was assessed using Harvey-Bradshaw Index, C-reactive protein and faecal calprotectin. For this analysis, trough levels ≥4.9 μg/mL were considered therapeutic.

RESULTS

Nineteen patients underwent 111 evaluations. Mean intra-patient drug levels from paired visits between cycles did not differ (visit1 cycle1: 4.81, cycle2: 5.21 μg/mL, P = 0.24, visit2 cycle1: 4.86, cycle2: 4.82, P = 0.91 and trough cycle1: 3.95, cycle2: 3.95, P = 0.99), irrespective of disease activity. Drug levels were stable over the first 9 days (visit 1-2), but declined to trough by a mean 1.06 and 0.89 μg/mL between visit 1 or 2, respectively (P < 0.001). Models using nontemporal factors (smoking, syringe delivery device) and levels at earlier visits accounted for 66-80% of the variance in trough levels. On receiver-operating curve analysis, thresholds identified in the first 9 days that predicted a therapeutic trough level were similar to the trough threshold itself, with high sensitivity but modest specificity.

CONCLUSION

While therapeutic drug monitoring should be performed at trough, a drug level ≥4.9 μg/mL obtained during the first 9 days predicts a therapeutic trough drug level with reasonable confidence.

Adalimumab in ulcerative colitis - efficacy, safety and optimization in the era of treat-to target

INTRODUCTION

Active ulcerative colitis is associated with significant morbidity and impairment to quality of life. Adalimumab is a welcome addition to the therapeutic armamentarium for clinicians treating patients with moderate-severe ulcerative colitis refractory to conventional therapies, an indication with few prior treatment options. It offers the convenience of self-injection and is most appropriate for outpatients with moderate disease activity. Areas covered: This review briefly summarizes data from well-designed clinical trials and observational real-life studies that demonstrate the safety and efficacy of adalimumab in UC. Particular attention is paid to newer studies, including those with objective treatment endpoints and pharmacokinetic outcomes that incorporate a treat to target approach in inflammatory bowel disease. Expert opinion: Adalimumab is effective for the induction and maintenance of remission in patients with moderate-severe ulcerative colitis refractory to conventional therapies. At currently approved doses, it is most suitable for use in outpatients with moderate disease activity; higher doses may be required for patients with more severe disease. The convenience of self-injection will make it popular for remote patients and it may be an appropriate option in patients in whom monotherapy, rather than combination therapy with an immunomodulator, is preferred.

Appropriateness of Testing for Anti-Tumor Necrosis Factor Agent and Antibody Concentrations, and Interpretation of Results

BACKGROUND & AIMS

The availability of tests for blood concentrations of anti-tumor necrosis factor (TNF) agents and antibodies against these drugs could improve dose selection for patients with inflammatory bowel disease (IBD). However, there is little consensus on when to test and how to interpret test results. We used the RAND/UCLA Appropriateness Method to determine when these tests are appropriate and how to clinically interpret their results.

METHODS

We conducted a systematic literature search in November 2013 to identify observational or experimental studies of the measurement of anti-TNF drug and antibody concentrations in patients with IBD and interpretation of their results. We developed 35 scenarios that assessed the appropriateness of testing and 143 scenarios that addressed clinical strategies in response to test results, and presented the findings to an expert panel. The appropriateness of each scenario was rated before and after an in-person meeting with the panel. Panelists rated the appropriateness of various clinical management options including changing therapy within class, switching out of class, adjusting drug dose or interval, adding or adjusting concomitant immune modulators, and doing nothing for each of 6 permutations of high versus low drug concentrations and high, low, or undetectable antibody concentrations. Disagreement was assessed using a validated index.

RESULTS

Assessment of anti-TNF drug and antibody concentrations was rated appropriate at the end of induction therapy in primary nonresponders, in secondary nonresponders, at least once during the first year of maintenance therapy, and following a drug holiday. Routine assessment in responders at the end of induction was rated uncertain. In nearly all scenarios, escalation of drug dosing was rated appropriate when drug concentration was low in the absence of antibodies, and switching within class was rated appropriate when antibodies were present. Other recommendations depended on the specific clinical scenario for which the test was obtained.

CONCLUSIONS

Based on the RAND/UCLA Appropriateness Method of analysis, an expert panel recommends testing for drug and antibody concentrations in many clinical scenarios. The appropriate timing and best way to respond to anti-TNF drug and antibody testing for IBD depends on the specific clinical scenario. These recommendations can help guide clinicians to best optimize anti-TNF therapy.

B-Cell Dysregulation in Crohn's Disease Is Partially Restored with Infliximab Therapy

BACKGROUND

B-cell depletion can improve a variety of chronic inflammatory diseases, but does not appear beneficial for patients with Crohn's disease.

OBJECTIVE

To elucidate the involvement of B cells in Crohn's disease, we here performed an 'in depth' analysis of intestinal and blood B-cells in this chronic inflammatory disease.

METHODS

Patients with Crohn's disease were recruited to study B-cell infiltrates in intestinal biopsies (n = 5), serum immunoglobulin levels and the phenotype and molecular characteristics of blood B-cell subsets (n = 21). The effects of infliximab treatment were studied in 9 patients.

RESULTS

Granulomatous tissue showed infiltrates of B lymphocytes rather than Ig-secreting plasma cells. Circulating transitional B cells and CD21low B cells were elevated. IgM memory B cells were reduced and natural effector cells showed decreased replication histories and somatic hypermutation (SHM) levels. In contrast, IgG and IgA memory B cells were normally present and their Ig gene transcripts carried increased SHM levels. The numbers of transitional and natural effector cells were normal in patients who responded clinically well to infliximab.

CONCLUSIONS

B cells in patients with Crohn's disease showed signs of chronic stimulation with localization to granulomatous tissue and increased molecular maturation of IgA and IgG. Therapy with TNFα-blockers restored the defect in IgM memory B-cell generation and normalized transitional B-cell levels, making these subsets candidate markers for treatment monitoring. Together, these results suggest a chronic, aberrant B-cell response in patients with Crohn's disease, which could be targeted with new therapeutics that specifically regulate B-cell function.

Concentrations of Adalimumab and Infliximab in Mothers and Newborns, and Effects on Infection

BACKGROUND & AIMS

Little is known about in utero exposure to and postnatal clearance of anti-tumor necrosis factor (anti-TNF) agents in neonates. We investigated the concentrations of adalimumab and infliximab in umbilical cord blood of newborns and rates of clearance after birth, and how these correlated with drug concentrations in mothers at birth and risk of infection during the first year of life.

METHODS

We performed a prospective study of 80 pregnant women with inflammatory bowel diseases at tertiary hospitals in Denmark, Australia, and New Zealand from March 2012 through November 2014: 36 received adalimumab and 44 received infliximab; 39 received concomitant thiopurines during pregnancy. Data were collected from medical records on disease activity and treatment before, during, and after pregnancy. Concentrations of anti-TNF agents were measured in blood samples from women at delivery and in umbilical cords, and in infants for every 3 months until the drug was no longer detected.

RESULTS

The time from last exposure to anti-TNF agent during pregnancy correlated inversely with the concentration of the drugs in the umbilical cord (adalimumab: r = -0.64, P = .0003; infliximab: r = -0.77, P < .0001) and in mothers at time of birth (adalimumab, r = -0.80; infliximab, r = -0.80; P < .0001 for both). The median ratio of infant:mother drug concentration at birth was 1.21 for adalimumab (95% confidence interval [CI], 0.94-1.49) and 1.97 for infliximab (95% CI, 1.50-2.43). The mean time to drug clearance in infants was 4.0 months for adalimumab (95% CI, 2.9-5.0) and 7.3 months for infliximab (95% CI, 6.2-8.3; P < .0001). Drugs were not detected in infants after 12 months of age. Bacterial infections developed in 4 infants (5%) and viral infections developed in 16 (20%), all with benign courses. The relative risk for infection was 2.7 in infants whose mothers received the combination of an anti-TNF agent and thiopurine, compared with anti-TNF monotherapy (95% CI, 1.09-6.78; P = .02).

CONCLUSIONS

In a prospective study of infants born to mothers who received anti-TNF agents during pregnancy, we detected the drugs until 12 months of age. There was an inverse correlation between the time from last exposure during pregnancy and drug concentration in the umbilical cord. Infliximab was cleared more slowly than adalimumab from the infants. The combination of an anti-TNF agent and thiopurine therapy during pregnancy increased the relative risk for infant infections almost 3-fold compared with anti-TNF monotherapy. Live vaccines therefore should be avoided for up to 1 year unless drug clearance is documented, and pregnant women should be educated on the risks of anti-TNF use.

Compassionate access anti-tumour necrosis factor-α therapy for ulcerative colitis in Australia: the benefits to patients

BACKGROUND

The efficacy of infliximab has been demonstrated in patients with both acute severe and moderate-severe ulcerative colitis (UC). However, there is a need for 'real-life data' to ensure that conclusions from trial settings are applicable in usual care. We therefore examined the national experience of anti-tumour necrosis factor-α (TNF-α) therapy in UC.

METHODS

Case notes review of patients with UC who had received compassionate access (CA) anti-TNF-α therapy from prospectively maintained inflammatory bowel disease databases of six Australian adult teaching hospitals.

RESULTS

Patients either received drug for acute severe UC (ASUC) failing steroids (n = 29) or for medically refractory UC (MRUC) (n = 35). In ASUC, the treating physicians judged that anti-TNF-α therapy was successful in 20/29 patients (69%); in these cases, anti-TNF-α was able to be discontinued (after 1-3 infusions in 19/20 responders) as clinical remission was achieved. Consistent with this perceived benefit, only 7/29 (24%) subsequently underwent colectomy during a median follow up of 12 months (interquartile range (IQR) 5-16). Eight of the 35 patients with MRUC (23%) required colectomy during a median follow up of 28 months (IQR 11-43). The majority of these patients (20/35 or 57%) had anti-TNF-α therapy for ≥4 months, whereas, 27/29 (93%) of ASUC patients had CA for ≤3 months.

CONCLUSIONS

These data show an excellent overall benefit for anti-TNF-α therapy in both ASUC and MRUC. In particular, only short-duration anti-TNF-α was required in ASUC. These real-life data thus support the clinical trial data and should lead to broader use of this therapy in UC.

How should immunomodulators be optimized when used as combination therapy with anti-tumor necrosis factor agents in the management of inflammatory bowel disease?

In the last 15 years the management of inflammatory bowel disease has evolved greatly, largely through the increased use of immunomodulators and, especially, anti-tumor necrosis factor (anti-TNF) biologic agents. Within this time period, confidence in the use of anti-TNFs has increased, whilst, especially in recent years, the efficacy and safety of thiopurines has been questioned. Yet despite recent concerns regarding the risk: benefit profile of thiopurines, combination therapy with an immunomodulator and an anti-TNF has emerged as the recommended treatment strategy for the majority of patients with moderate-severe disease, especially those who are recently diagnosed. Concurrently, therapeutic drug monitoring has emerged as a means of optimizing the dosage of both immunomodulators and anti-TNFs. However the recommended therapeutic target levels for both drug classes were largely derived from studies of monotherapy with either agent, or studies underpowered to analyze outcomes in combination therapy patients. It has been assumed that these target levels are applicable to patients on combination therapy also, however there are few data to support this. Similarly, the timing and duration of treatment with immunomodulators when used in combination therapy remains unknown. Recent attention, including post hoc analyses of the pivotal registration trials, has focused on the optimization of anti-TNF agents, when used as either monotherapy or combination therapy. This review will instead focus on how best to optimize immunomodulators when used in combination therapy, including an evaluation of recent data addressing unanswered questions regarding the optimal timing, dosage and duration of immunomodulator therapy in combination therapy patients.

Effect of intestinal resection on quality of life in Crohn's disease

INTRODUCTION

Patients with Crohn's disease have poorer health-related quality of life [HRQoL] than healthy individuals, even when in remission. Although HRQoL improves in patients who achieve drug-induced or surgically induced remission, the effects of surgery overall have not been well characterised.

METHODS

In a randomised trial, patients undergoing intestinal resection of all macroscopically diseased bowel were treated with postoperative drug therapy to prevent disease recurrence. All patients were followed prospectively for 18 months. C-reactive protein [CRP], Crohn's Disease Activity Index [CDAI], and faecal calprotectin [FC] were measured preoperatively and at 6, 12, and 18 months. HRQoL was assessed with a general [SF36] and disease-specific [IBDQ] questionnaires at the same time points.

RESULTS

A total of 174 patients were included. HRQoL was poor preoperatively but improved significantly [p < 0.001] at 6 months postoperatively. This improvement was sustained at 18 months. Females and smokers had a poorer HRQoL when compared with males and non-smokers, respectively. Persistent endoscopic remission, intensification of drug treatment at 6 months, and anti-tumour necrosis factor therapy were not associated with HRQoL outcomes different from those when these factors were not present. There was a significant inverse correlation between CDAI, [but not endoscopic recurrence, CRP, or FC] on HRQoL.

CONCLUSION

Intestinal resection of all macroscopic Crohn's disease in patients treated with postoperative prophylactic drug therapy is associated with significant and sustained improvement in HRQoL irrespective of type of drug treatment or endoscopic recurrence. HRQoL is lower in female patients and smokers. A higher CDAI, but not direct measures of active disease or type of drug therapy, is associated with a lower HRQoL.

The role of thiopurine metabolites in inflammatory bowel disease and rheumatological disorders

Thiopurines have been a cornerstone of medical management of patients with inflammatory bowel disease(IBD) and many rheumatological disorders. The thiopurines are metabolized to their end products, 6-methymercaptopurine (6MMP) and the 6-thioguanine nucleotides (6TGN), with 6TGN being responsible for thiopurine efficacy by causing apoptosis and preventing activation and proliferation of T-lymphocytes. In IBD, conventional weight-based dosing with thiopurines leads to an inadequate response in many patients. Utilizing measurement of these metabolites and then employing dose optimization strategies has led to markedly improved outcomes in IBD. Switching between thiopurines as well as the addition of low-dose allopurinol can overcome adverse events and elevate 6TGN levels into the therapeutic window. There is a paucity of data on thiopurine metabolites in rheumatological diseases and further research is required.

Optimizing conventional medical therapies in inflammatory bowel disease in 2014

Goals of therapy for inflammatory bowel disease have advanced beyond symptom control to the normalization of biomarkers of inflammation, and mucosal healing in particular, with the expectation that this will change the natural history of these diseases. Concurrent with higher treatment expectations has come an expanded therapeutic armamentarium to achieve these goals, and a greater ability to optimize each therapeutic class to maximize therapeutic benefits and minimize unnecessary treatment failures. In addition to these advances has come the evolution of therapeutic drug monitoring which is increasingly being utilized to optimize the use of immunomodulators and biologic therapies in particular. This review will outline the principals of optimization of the conventional medical therapies available to the clinician today.

The role of thiopurine metabolite monitoring in inflammatory bowel disease

Thiopurines are the mainstay of medical management in inflammatory bowel disease (IBD), especially in the maintenance of disease remission. Given the limited IBD armamentarium it is important to optimize each therapy before switching to an alternative drug. Conventional weight based dosing of thiopurines in IBD leads to intolerance or inefficacy in many patients. More recently increased knowledge of their metabolism has allowed for dose optimization using thiopurine metabolite levels, namely 6-thioguanine nucleotides and 6-methylmercaptopurine, with the potential for improved outcomes in patients with IBD. This review will outline the current understanding of thiopurine metabolism and pharmacogenomics and will describe the clinical application of this knowledge in the optimization of thiopurines in individual patients.

A phase 2 study of allogeneic mesenchymal stromal cells for luminal Crohn's disease refractory to biologic therapy

BACKGROUND & AIMS

Transplantation of peripheral blood stem cells has been successful therapy for small numbers of patients with Crohn's disease (CD), but requires prior myeloconditioning. Mesenchymal stromal cells (MSCs) escape immune recognition, so myeloconditioning is not required before their administration. We investigated the efficacy of allogeneic MSCs in patients with luminal CD.

METHODS

Our phase 2, open-label, multicenter study included 16 patients (21-55 y old; 6 men) with infliximab- or adalimumab-refractory, endoscopically confirmed, active luminal CD (CD activity index [CDAI], >250). Subjects were given intravenous infusions of allogeneic MSCs (2 × 10(6) cells/kg body weight) weekly for 4 weeks. The primary end point was clinical response (decrease in CDAI >100 points) 42 days after the first MSC administration; secondary end points were clinical remission (CDAI, <150), endoscopic improvement (a CD endoscopic index of severity [CDEIS] value, <3 or a decrease by >5), quality of life, level of C-reactive protein, and safety.

RESULTS

Among the 15 patients who completed the study, the mean CDAI score was reduced from 370 (median, 327; range, 256-603) to 203 (median, 129) at day 42 (P < .0001). The mean CDAI scores decreased after each MSC infusion (370 before administration, 269 on day 7, 240 on day 14, 209 on day 21, 182 on day 28, and 203 on day 42). Twelve patients had a clinical response (80%; 95% confidence interval, 72%-88%; mean reduction in CDAI, 211; range 102-367), 8 had clinical remission (53%; range, 43%-64%; mean CDAI at day 42, 94; range, 44-130). Seven patients had endoscopic improvement (47%), for whom the mean CDEIS scores decreased from 21.5 (range, 3.3-33) to 11.0 (range, 0.3-18.5). One patient had a serious adverse event (2 dysplasia-associated lesions), but this probably was not caused by MSCs.

CONCLUSIONS

In a phase 2 study, administration of allogeneic MSCs reduced CDAI and CDEIS scores in patients with luminal CD refractory to biologic therapy. ClinicalTrials.gov number, NCT01090817.