Randomised clinical trial: efficacy, safety and dosage of adjunctive allopurinol in azathioprine/mercaptopurine nonresponders (AAA Study).

BACKGROUND: Thiopurine hypermethylation towards 6-methylmercaptopurine (6MMP) instead of 6-thioguanine nucleotides (6TGN) is associated with inefficacy in patients with IBD. Allopurinol reverses such hypermethylation. AIMS: To prospectively determine efficacy of allopurinol-thiopurine combination and to compare 2 doses of allopurinol. DESIGN: In a multicentre, double-blind trial, patients with clinically active or steroid-dependent IBD and thiopurine shunting were randomised to 50 or 100 mg/d allopurinol and 25% of their screening thiopurine dose, which was subsequently optimised, aiming for 6TGN of 260-500 pmol/8x108 RBCs. The primary endpoint was steroid-free clinical remission at 24 weeks. RESULTS: Of 73 patients, 39 (53% [95% CI 42-65]) achieved steroid-free remission, (54% with 50 mg/d and 53% with 100 mg/d). 81% were able to discontinue steroids. Therapeutic 6TGN levels were achieved in both groups. Final thiopurine doses were lower with 100 mg/d allopurinol (P < 0.005). 6MMP: 6TGN ratio decreased from mean 64 to 4 (P < 0.001), being higher with 50 mg/d (6 ± 1.83) than for 100 mg/d ([1 ± 0.16], P = 0.003). Three patients on 50 mg/d failed to sustain low ratios at 24 weeks. Toxicity was minimal; three patients on 50 mg/d allopurinol developed transient leukopenia. Alanine aminotransferase concentrations decreased (P < 0.001) similarly in both arms. Faecal calprotectin levels at study end were lower in patients who achieved the primary endpoint (median 171 [85-541] vs 821[110-5892] ug/g, P = 0.03). CONCLUSIONS: Low-dose allopurinol-thiopurine combination safely reverses shunting and optimises 6TGN with associated improvement in disease activity. 100 mg/d allopurinol is preferable due to greater metabolite profile stability and lower thiopurine dose without additional toxicity.

Review article: consensus statements on therapeutic drug monitoring of anti-tumour necrosis factor therapy in inflammatory bowel diseases.

BACKGROUND: Therapeutic drug monitoring (TDM) in inflammatory bowel disease (IBD) patients receiving anti-tumour necrosis factor (TNF) agents can help optimise outcomes. Consensus statements based on current evidence will help the development of treatment guidelines. AIM: To develop evidence-based consensus statements for TDM-guided anti-TNF therapy in IBD. METHODS: A committee of 25 Australian and international experts was assembled. The initial draft statements were produced following a systematic literature search. A modified Delphi technique was used with 3 iterations. Statements were modified according to anonymous voting and feedback at each iteration. Statements with 80% agreement without or with minor reservation were accepted. RESULTS: 22/24 statements met criteria for consensus. For anti-TNF agents, TDM should be performed upon treatment failure, following successful induction, when contemplating a drug holiday and periodically in clinical remission only when results would change management. To achieve clinical remission in luminal IBD, infliximab and adalimumab trough concentrations in the range of 3-8 and 5-12 µg/mL, respectively, were deemed appropriate. The range may differ for different disease phenotypes or treatment endpoints-such as fistulising disease or to achieve mucosal healing. In treatment failure, TDM may identify mechanisms to guide subsequent decision-making. In stable clinical response, TDM-guided dosing may avoid future relapse. Data indicate drug-tolerant anti-drug antibody assays do not offer an advantage over drug-sensitive assays. Further data are required prior to recommending TDM for non-anti-TNF biological agents. CONCLUSION: Consensus statements support the role of TDM in optimising anti-TNF agents to treat IBD, especially in situations of treatment failure.

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.

Faecal calprotectin: current usage and perceived beneficial effects of third-party funding on rates of colonoscopy by Australian gastroenterologists.

BACKGROUND: Studies have suggested a diagnostic role for faecal calprotectin (FC) in patients with gastroenterological disorders. AIM: To investigate Australian gastroenterologists' (GE) views on FC use and to elicit factors that affect physicians' choices. METHODS: Electronic surveys were sent out to 405 consultants and 34 registrars in Australia. Respondents who answered <50% of the survey were excluded. RESULTS: In all, 140 participants provided a >50% response; 73% reported using FC in their clinical practice. Factors cited by non-users in restricting their FC use included cost (24%), availability (47%) and familiarity (18%). Even among users, 69% cited funding as a major deciding factor; 98 and 86% of FC users believed that the test is a reliable method of differentiating between inflammatory bowel disease (IBD) and irritable bowel syndrome (IBS) and assessing for mucosal healing in IBD respectively. Of non-users, 78 and 58%, respectively, would use FC to differentiate IBD from IBS and assess for mucosal healing in IBD, if FC testing was Medical Benefits Schedule (MBS) listed. Both users (79%) and non-users (68%) reported that use of FC to defer or avoid colonoscopies was likely if the test was MBS funded. CONCLUSION: Australian GE endorse the use of FC to discriminate between IBD and IBS, to check for mucosal healing in IBD and to reduce colonoscopy rates. Absence of MBS funding is an important factor contributing to the lack of usage of FC, in addition to the lack of familiarity with FC testing and availability.

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.

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.

Dose tailoring of anti-tumour necrosis factor-alpha therapy delivers useful clinical efficacy in Crohn disease patients experiencing loss of response.

BACKGROUND: 'Dose tailoring' of anti-tumour necrosis factor alpha (TNF-α) therapy in Crohn disease (CD), by dose escalation, or shortening of dosing intervals, has been suggested to regain clinical response following a flare in a proportion of patients. However, reported outcome data are sparse and none exists from Australia. METHOD: In an observational multicentre, retrospective study, the impact of anti-TNF-α dose tailoring on corticosteroid use, the need for surgery and physician perception of clinical efficacy was examined in a real-world setting at six Australian adult teaching hospitals. Demographics, disease characteristics, medications, indication for and duration of dose tailoring were documented. RESULTS: Fifty-five CD patients were identified as requiring dose tailoring and secondary loss of response was the indication in 96%. Either adalimumab (64%) or infliximab (36%) was dose escalated for a median of 5 months (range 1-47), with a median of 20 months follow up (range 3-65). At 3 months, dose tailoring reduced the mean number of days on high-dose corticosteroids (45 vs 23, P = 0.01). Most (78%) patients remained resection free, and 73% of physicians reported good clinical efficacy of dose tailoring. Of those who de-escalated therapy due to induction of remission, long-term (>12 months) follow up and complete data on steroid use were available in 15/28, with 12/15 (80%) remaining steroid free at 1 year. CONCLUSION: Short-term dose tailoring regains disease response in the majority of patients with CD. Of these, most will remain free of corticosteroids at 1 year after de-escalating therapy.

Systematic review: new serological markers (anti-glycan, anti-GP2, anti-GM-CSF Ab) in the prediction of IBD patient outcomes.

Traditionally, IBD diagnosis is based on clinical, radiological, endoscopic, and histological criteria. Biomarkers are needed in cases of uncertain diagnosis, or to predict disease course and therapeutic response. No guideline recommends the detection of antibodies (including ASCA and ANCA) for diagnosis or prognosis of IBD to date. However, many recent data suggest the potential role of new serological markers (anti-glycan (ACCA, ALCA, AMCA, anti-L and anti-C), anti-GP2 and anti-GM-CSF Ab). This review focuses on clinical utility of these new serological markers in diagnosis, prognosis and therapeutic monitoring of IBD. Literature review of anti-glycan, anti-GP2 and anti-GM-CSF Ab and their impact on diagnosis, prognosis and prediction of therapeutic response was performed in PubMed/MEDLINE up to June 2014. Anti-glycan, anti-GP2 and anti-GM-CSF Ab are especially associated with CD and seem to be correlated with complicated disease phenotypes even if results differ between studies. Although anti-glycan Ab and anti-GP2 Ab have low sensitivity in diagnosis of IBD, they could identify a small number of CD patients not detected by other tests such as ASCA. Anti-glycan Abs are associated with a progression to a more severe disease course and a higher risk for IBD-related surgery. Anti-GP2 Ab could particularly contribute to better stratify cases of pouchitis. Anti-GM-CSF Ab seems to be correlated with disease activity and could help predict relapses. These new promising biomarkers could particularly be useful in stratification of patients according to disease phenotype and risk of complications. They could be a valuable aid in prediction of disease course and therapeutic response but more prospective studies are needed.

Review article: vitamin D and inflammatory bowel disease--established concepts and future directions.

BACKGROUND: Understanding of the role of vitamin D in health and disease has increased markedly in the past decade, with its involvement extending well beyond traditional roles in calcium and phosphate homeostasis and musculoskeletal health. This conceptual expansion has been underpinned by identification and exploration of components of this axis including vitamin D-binding protein, key enzymes and receptors in multiple cell types, and a greater recognition of nonclassical autocrine and paracrine effects. Its influence in IBD remains uncertain. AIM: To review the role of vitamin D in bone health, immune regulation and cancer prevention in IBD, and to outline practical issues and limitations of its use. METHODS: An extensive online literature review including PubMed and Medline. RESULTS: In patients with IBD, the vitamin D axis provides an important and often underutilised pathway to preserving bone health. Furthermore, an exciting body of clinical and basic science research demonstrates that these pathways may have an integral part to play in regulation of the immune response in IBD, through effects on the intestinal barrier, antigen presenting cells and adaptive T cells. The possibility of chemoprevention requires further study. The optimal target level of 25-hydroxy vitamin D in patients with IBD is currently uncertain, as is the best therapeutic modality. CONCLUSIONS: Study of vitamin D pathways may result in the development of relatively inexpensive therapeutic options to optimise patient outcomes. Further prospective clinical research is required to address efficacy and long-term safety.

Setting priorities for comparative effectiveness research in inflammatory bowel disease: results of an international provider survey, expert RAND panel, and patient focus groups.

BACKGROUND: Comparative effectiveness research (CER) is an emerging field that compares the relative effectiveness of alternative strategies to prevent, diagnose, or treat patients who are typical of day-to-day practice. We developed a priority list of CER topics for inflammatory bowel disease (IBD). METHODS: Following the Institute of Medicine's approach, we developed and administered a survey to gastroenterologists asking for important CER topics in IBD. Two patient focus groups were convened to solicit additional CER studies. CER topics were presented to the expert panel using the RAND/UCLA methodology. Following initial ratings, the panel met to discuss and re-rate priorities. The top 10 CER topics were identified using a point-allocation system. RESULTS: Responses were collated into 234 CER topics across 21 categories, of which 87 were prioritized for discussion and re-rated. Disagreement regarding priorities was observed in 5 of 87 studies. We utilized a point-allocation system to prioritize the top-10 CER topics. These related to comparing the effectiveness of: biomarkers in IBD; withdrawal of anti-tumor necrosis factor (TNF) or immunomodulators for Crohn's disease in remission; mucosal healing as an endpoint of treatment; infliximab levels versus standard infliximab dosing; anti-TNF monotherapy versus combination therapy in patients failing thiopurines; safety of long-term treatment options; anti-TNF versus thiopurines for prevention of postoperative recurrence; and treatment options for steroid-refractory UC. CONCLUSIONS: We systematically developed a list of high-priority IBD topics for CER based on a survey of gastroenterologists, expert review, and patient input. This list may guide IBD research toward the most important CER studies.