Short-term tolerability and effectiveness of methotrexate monotherapy in adult patients with Crohn's disease: a retrospective study

Therapeutic drug monitoring of methotrexate in patients with Crohn's disease

BACKGROUND

Therapeutic drug monitoring (TDM) has the potential to improve efficacy and diminish side effects. Measuring methotrexate-polyglutamate (MTX-PG) in erythrocytes might enable TDM for methotrexate in patients with Crohn's disease (CD).

AIM

To investigate the relationship between MTX-PGs and methotrexate drug survival, efficacy and toxicity METHODS: In a multicentre prospective cohort study, patients with CD starting subcutaneous methotrexate without biologics were included and followed for 12 months. Primary outcome was subcutaneous methotrexate discontinuation or requirement for step-up therapy. Secondary outcomes included faecal calprotectin (FCP), Harvey Bradshaw Index (HBI), hepatotoxicity and gastrointestinal intolerance. Erythrocyte MTX-PGs were analysed at weeks 8, 12, 24 and 52 or upon treatment discontinuation.

RESULTS

We included 80 patients with CD (mean age 55 ± 13y, 35% male) with a median FCP of 268 μg/g (IQR 73-480). After the 12-month visit, 21 patients (26%) were still on subcutaneous methotrexate monotherapy. Twenty-one patients stopped because of disease activity, 29 because of toxicity, and four for both reasons. Five patients ended study participation or stopped methotrexate for another reason. A higher MTX-PG3 concentration was associated with a higher rate of methotrexate drug survival (HR 0.86, 95% CI 0.75-0.99), lower FCP (β -3.7, SE 1.3, p < 0.01) and with biochemical response (FCP ≤250 if baseline >250 μg/g; OR 1.1, 95% CI 1.0-1.3). Higher MTX-PGs were associated with less gastrointestinal intolerance. There was no robust association between MTX-PGs and HBI or hepatotoxicity.

CONCLUSIONS

Higher MTX-PG3 concentrations are related to better methotrexate drug survival and decreased FCP levels. Therefore, MTX-PG3 could be used for TDM if a target concentration can be established.

Effectiveness and tolerability of methotrexate monotherapy in Crohn's disease patients: a multicenter observational study

Background

Methotrexate monotherapy is recommended as a maintenance therapy for Crohn's disease (CD). However, long-term follow-up data are scarce.

Objectives

We aimed to examine the effectiveness and tolerability of methotrexate monotherapy in 94 CD patients from three inflammatory bowel disease Clinics in Korea.

Design

This was a multicenter retrospective observational study.

Methods

Patients with active CD treated with methotrexate monotherapy were included. Clinical characteristics, laboratory indicators, endoscopy indices were evaluated at baseline, 6, 12, and 24 months. Independent factors associated with long-term clinical and endoscopic outcomes were determined.

Results

Methotrexate was administered orally (70.2%) or parenterally (29.8%). The mean methotrexate induction dose was 15.3 ± 0.4 mg/week, and the mean duration of therapy was 26.2 months. Of 76 patients who were treated for >6 months, the clinical remission rates were 76.3%, 74.6%, and 80.0% at 6, 12, and 24 months, respectively, by per-protocol analysis. The mean CRP levels were 7.5 ± 1.3, 5.3 ± 1.2, 3.8 ± 0.7, and 2.6 ± 0.5 mg/L at 0, 6, 12, and 24 months, respectively. Of 31 patients who underwent follow-up endoscopy after 27.5 months, the endoscopic remission rate was 38.7%. Baseline hemoglobin level <10 g/dL was a significant independent factor negatively associated with clinical remission at 6 [odds ratio (OR): 0.023, 95% confidence interval (CI): 0.003-0.206, p = 0.001] and 12 (OR: 0.079, 95% CI: 0.009-0.699, p = 0.023) months. Parenteral administration was a significant independent factor positively associated with clinical remission (OR: 11.231, 95% CI: 1.027-122.811, p = 0.047) and endoscopic remission (hazard ratio: 4.711, 95% CI: 1.398-15.874, p = 0.012) at 12 months.

Conclusions

Methotrexate monotherapy was effective and tolerable as a maintenance therapy in CD patients.

Medical Management of Pediatric Inflammatory Bowel Disease (PIBD) in the Asia Pacific Region: A Position Paper by the Asian Pan-Pacific Society for Pediatric Gastroenterology, Hepatology, and Nutrition (APPSPGHAN) PIBD Working Group

Pediatric inflammatory bowel disease (PIBD) is rising rapidly in many industrialised and affluent areas in the Asia Pacific region. Current available guidelines, mainly from Europe and North America, may not be completely applicable to clinicians caring for children with PIBD in this region due to differences in disease characteristics and regional resources constraints. This position paper is an initiative from the Asian Pan-Pacific Society for Pediatric Gastroenterology, Hepatology and Nutrition (APPSPGHAN) with the aim of providing an up-to-date, evidence-based approach to PIBD in the Asia Pacific region, taking into consideration the unique disease characteristics and financial resources available in this region. A group of pediatric gastroenterologists with special interest in PIBD performed an extensive literature search covering epidemiology, disease characteristics and natural history, management and monitoring. Gastrointestinal infections, including tuberculosis, need to be excluded before diagnosing IBD. In some populations in Asia, the Nudix Hydrolase 15 (NUD15) gene is a better predictor of leukopenia induced by azathioprine than thiopurine-S-methyltransferase (TPMT). The main considerations in the use of biologics in the Asia Pacific region are high cost, ease of access, and potential infectious risk, especially tuberculosis. Conclusion: This position paper provides a useful guide to clinicians in the medical management of children with PIBD in the Asia Pacific region.