HHS Public Access Author manuscript J Gastrointest Dig Syst. Author manuscript; available in PMC 2017 October 19.

Similar documents
Azathioprine for Induction and Maintenance of Remission in Crohn s Disease

Positioning Biologics in Ulcerative Colitis

September 12, 2015 Millie D. Long MD, MPH, FACG

Efficacy and Safety of Treatment for Pediatric IBD

Common Questions in Crohn s Disease Therapy. Case

Recent Advances in the Management of Refractory IBD

Treatment Goals. Current Therapeutic Pyramids Crohn s Disease Ulcerative Colitis 11/14/10

Moderately to severely active ulcerative colitis

ORIGINAL ARTICLE. Abstract. Introduction

Position of Biologics in IBD Circa 2006: Top Down vs. Step Up Therapy

Ali Keshavarzian MD Rush University Medical Center

An Update on the Biologic Treatment for Patients with Inflammatory Bowel Disease. David A. Schwartz, MD

Mucosal healing: does it really matter?

Choosing and Positioning Biologic Therapy for Crohn s Disease: (Still) Looking for the Crystal Ball

Mono or Combination Therapy with. Individualized Approach

Crohn s Disease: Should We Treat Based on Symptoms or Based on Objective Markers of Inflammation?

Anne Griffiths MD, FRCPC. SickKids Hospital, University of Toronto. Buenos Aires, August 16, 2014

Biologics in IBD. Brian P. Bosworth, MD, NYSGEF Associate Professor of Medicine Weill Cornell Medical College

Immunogenicity of Biologic Agents and How to Prevent Sensitization

Optimizing the effectiveness of anti-tnf therapy in paediatric IBD

Initiation of Maintenance Treatment in Moderate to Severe New Onset Crohn s Disease

Biologic Therapy for Inflammatory. Is Top-Down Too Top-Heavy? S. Devi Rampertab, MD, FACG, AGAF Associate Professor of Medicine University of Florida

IBD Updates. Themes in IBD IBD management journey. New tools for therapeutic monitoring. First-line treatment in IBD

Indications for use of Infliximab

Medical Therapy for Pediatric IBD: Efficacy and Safety

Medical Management of Inflammatory Bowel Disease

Treating to Achieve a Target and Disease Monitoring in 2015: State of the Art

Efficacy and Safety of Treatment for Pediatric IBD

Mucosal Healing in Crohn s Disease. Geert D Haens MD, PhD University Hospital Gasthuisberg University of Leuven Leuven, Belgium

5/2/2018 SHOULD DEEP REMISSION BE A TREATMENT GOAL? YES! Disclosures: R. Balfour Sartor, MD

Clinical Study Clinical Study of the Relation between Mucosal Healing and Long-Term Outcomes in Ulcerative Colitis

Outcomes of immunosuppressors and biologic drugs in inflammatory bowel diseases: a real life experience

The following slides are provided as presented by the author during the live educa7onal ac7vity and are intended for reference purposes only.

Ulcerative colitis (UC) is a chronic inflammatory

CCFA. Crohns Disease vs UC: What is the best treatment for me? November

Update on Biologics in Ulcerative Colitis. Scott Plevy, MD University of North Carolina Chapel Hill, NC

Impact of endoscopic monitoring in postoperative Crohn s disease patients already receiving pharmacological prevention of recurrence

The legally binding text is the original French version TRANSPARENCY COMMITTEE OPINION. 3 October 2012

Join the conversation at #GIFORUMCCFA

Preventing post-operative recurrence

The small bowel capsule and management of patients

How to Optimize Induction and Maintenance Responses: Definitions and Dosing Advances in Inflammatory Bowel Disease December 6, 2009

Personalized Medicine in IBD: Where Are We in 2013

Mild-moderate Ulcerative Colitis Sequential & Combined treatments need to be tested. Philippe Marteau, Paris, France

Association Between Plasma Concentrations of Certolizumab Pegol and Endoscopic Outcomes of Patients With Crohn's Disease

John F. Valentine, MD Inflammatory Bowel Disease Program University of Utah

Personalized Medicine in IBD

Latest Treatment Updates for Ulcerative Colitis: Evolving Treatment Goals

IBD Biologicals and Novel therapeutic regimes. Dr S K Sinha Additional Professor Department of Gastroenterology PGIMER, Chandigarh

Anti tumor necrosis factor (TNF) agents have

Treatment of ulcerative colitis with adalimumab or infliximab: long-term follow-up of a single-centre cohort

DENOMINATOR: All patients aged 18 and older with a diagnosis of inflammatory bowel disease

Once Daily Dosing for Induction and Maintenance of Remission in Ulcerative Colitis

Beyond Anti TNFs: positioning of other biologics for Crohn s disease. Christina Ha, MD Cedars Sinai Inflammatory Bowel Disease Center

Medicine OPEN. Observational Study. 1. Introduction

Selby Inflamm Bowel Dis. 2008:14:

How do I choose amongst medicines for inflammatory bowel disease. Maria T. Abreu, MD

Endpoints for Stopping Treatment in UC

Crohn's Disease. The What, When, and Why of Treatment

Perianal and Fistulizing Crohn s Disease: Tough Management Decisions. Jean-Paul Achkar, M.D. Kenneth Rainin Chair for IBD Research Cleveland Clinic

WHY HAVE WE NOT FINALLY FIGURED OUT COMBINATION THERAPY?

Accepted Manuscript. Frank I. Scott, Siddharth Singh. S (19) DOI: Reference: YJCGH 56282

Tumor necrosis factor-alpha antibody for maintenace of remission in Crohn s disease (Review)

Dr David Epstein Vincent Pallotti Hospital and University of Cape Town

Ulcerative Colitis: Refining our Management and Incorporating Newer Concepts

Disclosures. What Do I Do When Anti-TNF Therapy Is Not Working Anymore? Fadi Hamid, M.D. Saint Luke s GI Specialists

Efficacy and Safety of Adalimumab in Ulcerative Colitis Refractory to Conventional Therapy in Routine Clinical Practice

NON INVASIVE MONITORING OF MUCOSAL HEALING IN IBD. THE ROLE OF BOWEL ULTRASOUND. Fabrizio Parente

Op#mizing)Management)in)IBD:) Mucosal)Healing)

Cover Page. The handle holds various files of this Leiden University dissertation.

Cancer Risk with IBD Therapies How to Discuss with your Patients?

Biological Therapy for Inflammatory Bowel Disease in Children

IBD Understanding Your Medications. Thomas V. Aguirre, MD Santa Barbara GI Consultants

Severe IBD: What to Do When Anti- TNFs Don t Work?

Anti-tumour necrosis factor treatment of inflammatory bowel disease in liver transplant recipients

ustekinumab 130mg concentrate for solution for infusion and 90mg solution for injection (Stelara ) SMC No. (1250/17) Janssen-Cilag Ltd

Positioning New Therapies

Predicting the natural history of IBD. Séverine Vermeire, MD, PhD Department of Gastroenterology University Hospital Leuven Belgium

2nd Nottingham IBD Masterclass, 2017

The evaluation and treatment of patients with Crohn s

Clinical Course of Infliximab Treatment in Korean Pediatric Ulcerative Colitis Patients: A Single Center Experience

Agenda. Predictive markers in IBD. Management of ulcerative colitis. Management of Crohn s disease

Withdrawal of drug therapy in patients with quiescent Crohn s disease

Adalimumab Treatment in Pediatric-Onset Crohn s Disease Patients after Infliximab Failure: A Single Center Study

To help protect your privacy, PowerPoint prevented this external picture from being automatically downloaded. To download and display this picture,

Crohn's Disease. The What, When, and Why of Treatment

The Best of IBD at UEGW (Crohn s)

Evidence review for Surrey Prescribing Clinical Network SUMMARY

Activity and Endoscopic measures : Crohn s disease. Jean-Frederic COLOMBEL Justin Cote-Daigneault Icahn Medical School at Mount Sinai, New York

Crohn's Disease. The What, When, and Why of Treatment

U of Cape Town, South Africa, 10 U of Washington, Seattle, WA,USA, 11 CHRU de Lille, Hôpital Claude Huriez, Lille, France, 12

COPYRIGHT. Inflammatory Bowel Disease What Every Clinician Needs to Know. Adam S. Cheifetz, MD. Director, Center for Inflammatory Bowel Disease

ENTYVIO (VEDOLIZUMAB)

Efficacy of Adalimumab in Korean Patients with Crohn s Disease

PD Dr. med. R. Wiest / Dr. med. P. Juillerat, MSc. Donnerstag 18 ten Oktober 2012 UPDATE PROKTOLOGIE: Konservative Behandlungsmöglichkeiten?

INFLIXIMAB FOR PREVENTION OF POST-OPERATIVE CROHN S DISEASE RECURRENCE: THE PREVENT TRIAL

Communicating with the IBD Patient: How to convey risks and benefits

Bridges to excellence quality indicators in inflammatory bowel disease (IBD): differences between IBD and non-ibd gastroenterologists

Clinical guideline Published: 10 October 2012 nice.org.uk/guidance/cg152

Transcription:

Rate and Predictors of Endoscopic Mucosal Healing in Biologic Naive Patients with Inflammatory Bowel Disease by Azathioprine Treatment: A Real World, 10 Years Experience from a Single Centre in Turkey Metin Basaranoglu 1,2,*, Atilla Ertan 3, Sanju Mathew 4,5, Sonia Michael Najjar 6, Aftab Ala 4,5, Ali Eba Demirbag 2, and Hakan Senturk 1 1 Department of Internal Medicine, Gastroenterology Division, Bezmialem Vakif University Faculty Hospital, Fatih, 34000, Istanbul, Turkey 2 Gastroenterology and Gastrointestinal Surgery Divisions, Türkiye Yüksek Ihtisas Hospital, Sihhiye, 06010, Ankara, Turkey 3 Department of Internal Medicine, Gastroenterology Division, Ertan Digestive Center, The University of Texas Medical School, Houston, 6414, Texas, USA 4 Department of Gastroenterology and Hepatology, Royal Surrey County Hospital NHS Foundation Trust, Guildford, Surrey, GU2 7XX, UK 5 Faculty of Health Medical Sciences, Health Management University of Surrey Guildford, Surrey, GU2 7XH, UK 6 Associate Dean of Research and Innovation, Heritage College of Osteopathic Medicine Office of Research and Grants Irvine Hall, Room 220B, 1 Ohio University, USA Abstract HHS Public Access Author manuscript Published in final edited form as: J Gastrointest Dig Syst. 2016 August ; 6(4):. doi:10.4172/2161-069x.1000467. Background There is increasing evidence that endoscopic mucosal healing (EMH) is a key target in inflammatory bowel disease (IBD) therapy. However, there is limited evidence of EMH rates with conventional IBD therapy outside of Western population groups. Aım To evaluate the role of azathioprine (AZA) in inducing EMH in IBD patients. Methods Patients with inflammatory bowel disease were evaluated in terms of endoscopic mucosal healing and the incidence of surgical interventions during the azathioprine treatment between 1995 to 2014. Results A total of 120 inflammatory bowel disease patients were enrolled. Endoscopic mucosal healing was found in 37% patients with inflammatory bowel disease (42% in chronic ulcerative colitis and 33% in Crohn s disease). Male gender had a negative impact on the efficacy of This is an open-access article distributed under the terms of the Creative Commons Attribution License; which permits unrestricted use; distribution; and reproduction in any medium; provided the original author and source are credited. * Corresponding author: Dr. Metin Basaranoglu, Department of Internal Medicine, Gastroenterology and Hepatology Division, Bezmialem Vakif University Medical School, Asagi Gureba, Fatih, Istanbul, 34000, Turkey, Tel: +90-212-5540570; Fax: +90-212-5540570; metin_basaranoglu@yahoo.com.

Basaranoglu et al. Page 2 azathioprine (P<0.05). Responder inflammatory bowel disease patients were older (age at the IBD diagnose) than the nonresponder (P<0.05). Azathioprine therapy reduced the number of the surgical interventions (P<0.05). Conclusıon We showed that azathioprine therapy significantly induced endoscopic mucosal healing in biologic naïve patients with active inflammatory bowel disease as well as decreasing the surgical interventions, with negative predictive factors identified by a younger age at IBD presentation and male gender. Keywords Crohn s disease; Thiopurines; Azathioprine treatment; Endoscopic mucosal healing; Inflammatory bowel disease Introduction Inflammatory bowel disease (IBD) including Ulcerative Colitis (UC) and Crohn s Disease (CD) are chronic, progressive and relapsing disorders [1]. Both UC and CD are characterized by inflammation and ulceration with genetic and environmental factors that contribute to disease pathogenesis. Endoscopic mucosal healing (EMH) is now taken as a key treatment-goal in IBD management; achieving a positive modification in the natural history of IBD, and better outcomes with regard to steroid-free remission, surgery and hospitalization [2 5]. Current medical strategies for moderate to severe IBD include the use of corticosteroids, immunosuppressants (such as Azathioprine (AZA) and 6-Mercaptopurine) and biologic therapies. Newer biologic therapies (such as anti-tnf-α agents) have produced significant treatment gains in IBD, but safety and in particular economic considerations have raised concerns about its long term utilization in patients. EMH can be achieved with both AZA and biologics, but with reported efficacy rates that differ among published studies for each agent, and that are based primarily upon White- Western populations. The incidence and prevalence of IBD is rising across Asia, but there is limited data on EMH responses across these countries, with most published studies based in East and South East Asia [6,7]. Turkey is a unique country that borders both Europe and Asia, with over 90% of its land mass in Asia. IBD incidence rates in Turkey resemble that seen in the Middle East, with no published studies of EMH rates in the region [8]. Assessing EMH responses in this population is therefore an important addition to our understanding of available treatment efficacy in moderate to severe Asian IBD patients. As such, our study aims were to evaluate the role of Azathioprine (AZA) in inducing EMH in biologic naïve IBD patients in our centre in Turkey, looking additionally for predictive factors of a positive mucosal healing response under AZA.

Basaranoglu et al. Page 3 Significance of this Study What is already known about this subject The current medical management of moderate-severe IBD consists of corticosteroids and immunosuppressants. New therapeutic approaches (such as anti-tnfα antibodies) led to a reduction in the mortality rate and a favorable modification in the natural history of patients with CD. Safety and especially economic issues have increasingly raised concerns about the long term use of biologics as a maintenance therapy in patients with IBD. What are the new findings We evaluated the role of azathioprine for inducing endoscopic mucosal healing on patients with inflammatory bowel disease and to characterize factors predicting endoscopic mucosal healing by the azathioprine therapy in this study, beside the incidence of surgical interventions during the azathioprine treatment at a single tertiary gastroenterology between 1995 2014. We showed that azathioprine therapy significantly induced endoscopic mucosal healing in azathioprine native patients with active inflammatory bowel disease through decreasing the frequency of the surgical interventions. Male gender and young age at diagnosis were negative predictors of the response. We showed that azathioprine therapy significantly induced endoscopic mucosal healing in biologic naïve patients with active inflammatory bowel disease as well as decreasing the surgical interventions. How might it impact on clinical practice in the foreseeable future? Azathioprine by a low cost will decrease the health budget in IBD. In particular, we must use more expensive biologics in selected patients or patients without responce to azathioprine. Mucosal healing should be a treatment goal because it may change the natural course of IBD. Mucosal healing may be associated with better long-term outcomes and reduced risk of surgery. Materials and Methods Study design and patient characteristics This was a retrospective study, with a total of 2700 patients with IBD identified between 1995 to 2014 at our single-center. The study was approved by the ethics committee, and data was collected on patients treated with AZA from Inflammatory Bowel Disease clinics. Eligible patients were at least 18 years of age, and had established IBD for at least 3 months; with a Crohn s Disease Activity Index (CDAI) score of 220 to 450 points, and severely

Basaranoglu et al. Page 4 Dose of azathioprine active UC as defined according to the total Mayo score [5]. Patients were excluded if they had started AZA at another hospital, or if AZA was used primarily for another disease indication. Additionally, patients with the short bowel syndrome, an ostomy, a symptomatic, recent abdominal surgery (within 6 months), a history of Tuberculosis (or other granulomatous infections), a positive chest radiograph or tuberculin skin test were also excluded. Therefore, in total 120 patients with IBD were included in the study; 75 patients with CD, and 45 with UC. Patients had regular clinical follow-up and endoscopic examinations at our clinic, and the efficacy of AZA treatment was only assessed if treatment had been continued for at least 4 months. EMH was defined by a full lower GI endoscopy showing no inflammation, mucus, granularity, ulceration or vascular invisibility in the rectum, colon and distal ileum. Patients were considered missed to follow up if information was lacking on clinical or endoscopic evaluation during AZA therapy. Disease extent and treatment response was defined by endoscopic and histological evidence. Efficacy data was based on the findings from the last evaluation. AZA dose was increased to the nearest approximation of 2.5 mg per kilogram per day with 50 mg tablets (125 to 250 mg per day). Systemic corticosteroids was initiated (for patients not receiving them at baseline) with the dose until week 4 (maximum allowed dose, 40 mg per day). After 4th week, the dose was tapered and stopped until week 12. The continued use of oral 5-aminosalicylic acid (5-ASA) compounds was allowed. Evaluation of efficacy and safety Ileocolonoscopy was performed at baseline and again at week 16 or later in each patient who had mucosal active disease at the baseline examination. Each colonoscopy was interpreted by one of the experienced endoscopists for IBD patients, who were unaware of the study and the timing of the procedure. Corticosteroid-free clinical remission was defined in patients who had not received systemic corticosteroids for at least 4 wk. EMH was defined as the absence of ulceration and active inflammation by visual assessment or endoscopy score of 0 1 at week 16 in patients. Primary and secondary end points Statistical analyses The primary efficacy end point was the rate of corticosteroid-free EMH at least at week 16. Secondary end point was effectiveness of AZA on surgical interventions of patients with IBD. The data was coded and recorded in a computer using an IBM Statistical Package for the Social Sciences (SPSS; Armonk, NY, United States) for the Windows version 17.0 (2007). The Chi-square and Fisher s exact tests were used for comparing the responder and nonresponder groups for the distribution of the disease (UC and CD), gender, IBD related surgery percent prior to AZA therapy and during the AZA therapy (intestinal resection), efficacy of AZA in previously not-operated and operated patients with CD, and smoking

Basaranoglu et al. Page 5 Results Patient demographics habit. Age at the IBD diagnosis and duration of AZA therapy were compared by Student s t test between responder and non-responder groups because of parametric variables. Duration prior to the AZA therapy was compared by Mann Whitney U test due to non-parametric variables. P<0.05 was considered statistically significant in all the tests. Overall, 2700 patients with IBD were seen in our specialty clinic at the Türkiye Yüksek Ihtisas Hospital, Ankara from 1995 to 2014; 702 patients with CD, and 1,998 with UC. A total of 120 patients treated with AZA fulfilled inclusion and exclusion criteria and were included in the study. Of the 120 patients with IBD, there were 45 (37.5%) patients with UC and 75 (62.5%) with CD, as shown in Table 1. The mean age at IBD diagnosis was 36.9 ± 12.3 years (median: 36.5, range: 11 72) with a male to female ratio of 2:1. The mean period between IBD diagnosis and commencing AZA was 39.8 months (median: 24 months, range: 4 264). Mean duration of AZA therapy (months) was 31.5 ± 24.7 months (median: 25.5, range 4 113) in IBD patients, with a duration of 31.2 ± 25.7 (median: 24, range: 4 90) in responders and 31.6 ± 24.3 (median: 26.5, range: 4 113) in non-responders (P>0.05), respectively. Remission rates with AZA therapy Response to therapy with EMH and steroid-free remission was achieved by 37% (44/120) of biologic naive IBD patients after at least 16 weeks of AZA therapy, as shown in Table 1. Response was seen in 42% (19/45) of UC patients, and 33% (25/75) of CD patients. Patients who achieved EMH remained in endoscopic remission during followup, up to a total of 113 months. Surgical intervention rates were reduced in those patients who responded to AZA therapy, from 18.4% to 4.5% in patients who achieved EMH with AZA (p=0.031). Patients who failed to respond to AZA had a younger age at IBD diagnosis compared to responders (36.1 yrs ± 12.3 vs. 38.1 ± 12.3, P=0.049), and male gender was also significantly associated with a negative response to AZA therapy (72.2% vs. 27.8%, p=0.013), as shown in Table 1. In patients with CD (75/120) there was no difference between responders and nonresponders for smoking rates and Isoniazid use. Azathioprine therapy reduced the number of the surgical interventions in patients with CD, but without a statistical significance as shown in Table 2. There was no difference for the EMH rates in CD group by gender. Of the 50 patients with CD who failed to respond to AZA, 33 patients were managed with biologic therapy (Table 2). EMH was achieved in 30% of this subgroup treated with biologic therapy at 12 month follow-up. EMH rates were 50% in those patients diagnosed <2 years, vs. 26% in patients diagnosed >2 years.

Basaranoglu et al. Page 6 Discussion Azathioprine (AZA) is a purine analogue that competitively inhibits the biosynthesis of purine nucleotides, and is widely available as an immunosuppressant at relatively low cost [5 9]. Side-effects of therapy can include leucopenia, pancreatitis, fever and rash, which can sometimes limit their use in clinical practice. However, use and efficacy of AZA in IBD maintenance has been validated as in clinical trials and meta-analyses [2,9 12]. Azathioprine is a standard therapy for moderately or severely active IBD in many countries, particularly in middle to low-income countries. Biologics and now biosimilars are increasingly used in IBD, but with higher drug costs and health-system infrastructure implications that limits availability in many countries [13]. There is a paucity of data on EMH responses with AZA in Asia, and whilst IBD phenotype and complication risks seem unchanged between Asian and White-Western populations, there are heterogeneities between population groups (including genetic susceptibility), that make it important to improve our understanding of AZA efficacy in diverse IBD populations [6]. Therefore, we evaluated the role of AZA to achieve EMH in biologic naive patients with IBD, as well as identify EMH responses in those members of our CD patient cohort who were able to receive biologics therapy in our centre. Although clinical symptoms and quality of life are the key treatment indicators for patients, we chose mucosal healing as the primary treatment end-point of our study given the increasing recognition of its role by IBD physicians [1,4]. There are several problems with using EMH in clinical studies, including that mucosal healing may not always be achieved, and that clinical response and mucosal healing may not correlate [1,3,7,14 16]. However, overall EMH is correlated with better and prolonged steroid-free remission, and understanding EMH responses across diverse population groups with standard and newer biologic therapies remains important. We showed that AZA therapy induced EMH in 42.2% (19/45) of severe-active UC patients, and 33.3% (25/75) of moderately-active CD patients who were naïve to biologic therapies in our Turkish cohort. AZA response was associated with statistically significant reduction in surgical interventions in these patients (p=0.031), in keeping with previous reports [17]. Negative predictive factors of response to AZA included a younger age at IBD diagnosis age, and male gender (p=0.049 and p=0.013 respectively). The main limitations of our study include its retrospective nature, and the relatively small number of patients eligible for study inclusion. Reported EMH rates with AZA and biologic therapy vary between published studies, but our results are similar to previous reports. A randomized controlled trial of AZA compared to 5- ASA for steroid-dependent, moderate or severe UC reported endoscopic remission in 53% of AZA patients, with a recent randomized study of IFX compared to AZA reporting endoscopic mucosal healing in 36.8% receiving AZA alone, also at week 16 [13,17,18]. Evidence for EMH in CD is limited for both AZA and biologic therapies including Infliximab (IFX) [14 21], with differences in published methodology and outcome measures [20,21]. A recent post-hoc analysis of the SONIC study showed EMH rates in 16% of

Basaranoglu et al. Page 7 Acknowledgments References patients treated with AZA monotherapy at 26 weeks, compared to 30% in those patients treated with IFX [16]. However this is lower than reports achieved from earlier studies of AZA, with EMH noted in up to 73% of CD patients (mean duration of AZA therapy 24.4 +/ 13.7 months) [21]. Most of these studies are based on White-Western populations, and of the few comparative studies available in Asia, complete or near EMH was achieved with AZA in 25% (9/36) of small bowel CD patients at 12 months, and 56% (20/36) of CD patients at 24 month followup with AZA therapy [14]. Overall, there are inconsistencies in EMH rates between different studies that are likely to relate to heterogeneity in study design, drug dosing and disease severity [1,4,5,20,21,14]. These differences preclude direct study and population comparisons, but EMH rates identified in our Turkish IBD cohort seem comparable to other (predominately Western) populations. In conclusion, our understanding of the efficacy of AZA in diverse IBD population groups is of significance given the important role that this agent plays in many non-high income countries. Our study highlights the efficacy of AZA in achieving EMH in biologic naïve severe-uc and moderate-cd patients, and suggests a younger age at diagnosis and male gender as being negative predictors of AZA mucosal-healing response. Financial Support Supported by AbbVie, UCB, Pfizer and Takeda to Dr. Atilla Ertan. Professor Aftab Ala is supported by the Clinical Research Network, National Instutite for Health and Research (NIH) with Grant Numbers R01 DK054254, R01 DK083850 and R01 HL112248 (to Sonia M. Najjar). 1. Papi C, Fascì-Spurio F, Rogai F, Settesoldi A, Margagnoni G, et al. Mucosal healing in inflammatory bowel disease: treatment efficacy and predictive factors. Dig Liver Dis. 2013; 45:978 985. [PubMed: 24018244] 2. Neurath MF, Travis SP. Mucosal healing in inflammatory bowel diseases: a systematic review. Gut. 2012; 61:1619 1635. [PubMed: 22842618] 3. Gecse KB, Khanna R, van den Brink GR, Ponsioen CY, Löwenberg M, et al. Biosimilars in IBD: hope or expectation? Gut. 2013; 62:803 807. [PubMed: 23503043] 4. Peyrin-Biroulet L, Ferrante M, Magro F, Campbell S, Franchimont D, et al. Results from the 2nd Scientific Workshop of the ECCO. I: Impact of mucosal healing on the course of inflammatory bowel disease. J Crohns Colitis. 2011; 5:477 483. [PubMed: 21939925] 5. Armuzzi A, Van Assche G, Reinisch W, Pineton de Chambrun G, Griffiths A, et al. Results of the 2nd scientific workshop of the ECCO (IV): therapeutic strategies to enhance intestinal healing in inflammatory bowel disease. J Crohns Colitis. 2012; 6:492 502. [PubMed: 22406343] 6. Thia KT, Loftus EV, Sandborn WJ, Yang SK. An update on the epidemiology of inflammatory bowel disease in Asia. Am J Gastroenterol. 2008; 103:3167 3182. [PubMed: 19086963] 7. Yu LF, Zhong J, Cheng SD, Tang YH, Miao F. Low-dose azathioprine effectively improves mucosal healing in Chinese patients with small bowel disease. J Dig Dis. 2014; 15:180 1878. [PubMed: 24387287]

Basaranoglu et al. Page 8 8. Tozun N, Atug O, Imeryuz N, Hamzaoglu HO, Tiftikci A, et al. Clinical characteristics of inflammatory bowel disease in Turkey: A multicentre epidemiological survey. J Clin Gastroenterol. 2009; 43:51 57. [PubMed: 18724251] 9. Kennedy NA, Kalla R, Warner B, Gambles CJ, Musy R, et al. Thiopurine withdrawal during sustained clinical remission in inflammatory bowel disease: relapse and recapture rates, with predictive factors in 237 patients. Aliment Pharmacol Ther. 2014; 40:1313 1323. [PubMed: 25284134] 10. Louis E. Strategic use of immunosuppressants and anti-tnf in inflammatory bowel disease. Dig Dis. 2013; 31:207 212. [PubMed: 24030227] 11. Mehta SJ, Silver AR, Lindsay JO. Review article: strategies for the management of chronic unremitting ulcerative colitis. Aliment Pharmacol Ther. 2013; 38:77 97. [PubMed: 23718288] 12. López-Palacios N, Mendoza JL, Taxonera C, Lana R, López-Jamar JM, et al. Mucosal healing for predicting clinical outcome in patients with ulcerative colitis using thiopurines in monotherapy. Eur J Intern Med. 2011; 22:621 625. [PubMed: 22075292] 13. Rogler G, Bernstein CN, Sood A, Goh KL, Yamamoto-Furusho JK, et al. Role of biological therapy for inflammatory bowel disease in developing countries. Gut. 2012; 61:706 712. [PubMed: 21997549] 14. D Haens G, Geboes K, Rutgeerts P. Endoscopic and histologic healing of Crohn s (ileo-) colitis with azathioprine. Gastrointest Endosc. 1999; 50:667 671. [PubMed: 10536324] 15. Ferrante M, Colombel JF, Sandborn WJ, Reinisch W, Mantzaris GJ, et al. Validation of endoscopic activity scores in patients with Crohn s disease based on a post hoc analysis of data from SONIC. Gastroenterology. 2013; 145:978 986.e5. 2013. [PubMed: 23954314] 16. Peyrin-Biroulet L, Oussalah A, Williet N, Pillot C, Bresler L, et al. Impact of azathioprine and tumour necrosis factor antagonists on the need for surgery in newly diagnosed Crohn s disease. Gut. 2011; 60:930 936. [PubMed: 21228429] 17. Panaccione R, Ghosh S, Middleton S, Márquez JR, Scott BB, et al. Combination therapy with infliximab and azathioprine is superior to monotherapy with either agent in ulcerative colitis. Gastroenterology. 2014; 146:392 400. [PubMed: 24512909] 18. Sandborn WJ, Gasink C, Gao LL, Blank MA, Johanns J, et al. Ustekinumab induction and maintenance therapy in refractory Crohn s disease. N Engl J Med. 2012; 367:1519 1528. [PubMed: 23075178] 19. Schreiber S, Colombel JF, Bloomfield R, Nikolaus S, Schölmerich J, et al. Increased response and remission rates in short-duration Crohn s disease with subcutaneous certolizumab pegol: an analysis of Precise 2 randomized maintenance trial data. Am J Gastroenterol. 2010; 105:1574 1582. [PubMed: 20234346] 20. Lichtenstein GR, Thomsen O, Schreiber S, Lawrance IC, Hanauer SB, et al. Continuous therapy with certolizumab pegol maintains remission of patients with Crohn s disease for up to 18 months. Clin Gastroenterol Hepatol. 2010; 8:600 609. [PubMed: 20117244] 21. Buchman AL, Katz S, Fang JC, Bernstein CN, Abou-Assi SG. Teduglutide, a novel mucosally active analog of glucagon-like peptide-2 (GLP-2) for the treatment of moderate to severe Crohn s disease. Inflamm Bowel Dis. 2010; 16:962 973. [PubMed: 19821509]

Basaranoglu et al. Page 9 Table 1 Characteristics of selected inflammatory bowel diseases patients before and during the azathioprine treatment. Responder means patients with endoscopic mucosal healing; non-responder means patients with no endoscopic mucosal healing. Measured In IBD group Responder Non responder p Number of the patients 120 patients 37% (44 patients) 63% (76 patients) Patients with CUC 37.50% (45 patients) 42.20% (19 patients) 57.8% (26 patients) P=0.328 Patients with CD 62.50% (75 patients) 33.30% (25 patients) 66.70% (50 patients) % male in IBD 60% (72 patients) 27.80% (18 patients) 72.20% (54 patients) P=0.013 a Age at the IBD diagnosis (years) Duration, prior to the azathioprine therapy (months) Duration of azathioprine used (months) IBD related surgery % prior to the azathioprine therapy IBD related surgery % during the azathioprine therapy (intestinal resection) 36.9 ± 12.3 (median:36.5, range: 11 72) 39.8 ± 52.5 (median: 24, range: 0 264) 31.5 ± 24.7 (median: 25.5, range: 4 113) 38.1 ± 12.3 (median: 39.5, range: 17 58) 56.2 ± 69.2 (median: 24, range: 0 264) 31 ±2 5.7 (median: 24, range: 4 90) 36.1 ± 12.4 (median: 35, range: 11 72) 30.4 ± 37.1 (median: 17.5, range: 0 204) 31.7 ± 24.3 (median: 26.5, range: 4 113) P=0.049 a P=0.147 P=0.933 20% (24 patients) 33.30% (8 patients) 66.70% (16 patients) P=0.705 13.30% (16 patients) 12.50% (2 patients) 87.50% (14 patients) P=0.031a P<0.05 was statistically significant. IBD: Inflammatory bowel diseases; CUC: Chronic ulcerative colitis; CD: Crohn s disease.

Basaranoglu et al. Page 10 Table 2 Results of 75 biologic naive patients with Crohn s disease by azathioprine therapy. Efficacy of azathioprine in previously not -operated patients with Crohn s disease Efficacy of azathioprine in previously Crohn s disease related surgery patients Number of the patients % Responder Non responder p 70.7% (53 patients) 34% (18 patients) 66% (35 patients) P=0.858 29.3% (22 patients) 31.8% (7 patients) 68.2% (15 patients) P=1.000 (%) rate of non-smoking 32 patients (42.7%) 34.4% (11 patients) 65.6% (21 patients) P=0.98 Crohn s disease related surgery need during the azathioprine therapy 17.3% (13 patients) 15.4% (2 patients) 84.6% (11 patients) P=0.198