{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,11,4]],"date-time":"2026-11-04T08:46:00Z","timestamp":1793781960263,"version":"4.6.1"},"reference-count":38,"publisher":"Ovid Technologies (Wolters Kluwer Health)","issue":"2","license":[{"start":{"date-parts":[[2025,1,23]],"date-time":"2025-01-23T00:00:00Z","timestamp":1737590400000},"content-version":"unspecified","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by-nc-sa\/4.0"}],"content-domain":{"domain":["lww.com","ovid.com"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2025,3]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Background:<\/jats:title>\n                    <jats:p>The emergence of tumor necrosis factor inhibitors (anti-TNF) has considerably changed the management of inflammatory bowel disease (IBD) in patients who do not respond to traditional therapies. This study assesses the prevalence of anti-TNF drug levels (DLs) and antibodies (ATAbs) in patients with IBD in Saudi Arabia and explores their associations with IBD type and prior anti-TNF failure.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods:<\/jats:title>\n                    <jats:p>This cross-sectional study included patients aged 14\u201375 years diagnosed with Crohn\u2019s disease (CD) or ulcerative colitis (UC), treated with anti-TNF medications at King Fahad Medical City over January 2016 to December 2022. Data were analyzed using descriptive statistics, Mann\u2013Whitney U test, Kruskal\u2013Wallis test, Pearson\u2019s Chi-squared test, and multinomial logistic regression.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results:<\/jats:title>\n                    <jats:p>\n                      Among 392 patients with IBD (median age, 31 years), 75.8% were diagnosed with CD and 24.2% with UC. Anti-TNF levels were subtherapeutic in 27.0% patients, therapeutic in 21.5%, and supratherapeutic in 51.5%. ATAbs were negative in 73.1% patients, weakly positive in 9.8%, and positive in 17.1%. Subtherapeutic anti-TNF levels were significantly associated with positive ATAbs (\n                      <jats:italic toggle=\"yes\">P<\/jats:italic>\n                      &lt; 0.001). Prior anti-TNF therapy failure was observed in 37.2% cases, with 15.3% showing immunogenicity. No significant demographic differences were noted across ATAbs groups.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion:<\/jats:title>\n                    <jats:p>We highlight the prevalence of subtherapeutic and supratherapeutic anti-TNF levels among patients with IBD in Saudi Arabia and their association with ATAbs. The findings underscore the importance of monitoring anti-TNF DLs and ATAbs to optimize treatment outcomes in IBD management. Future research should focus on the longitudinal impact of these factors and explore genetic predictors of treatment response.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.4103\/sjg.sjg_245_24","type":"journal-article","created":{"date-parts":[[2025,1,24]],"date-time":"2025-01-24T02:00:10Z","timestamp":1737684010000},"page":"82-92","update-policy":"https:\/\/doi.org\/10.1097\/lww.0000000000001000","source":"Crossref","is-referenced-by-count":5,"title":["Prevalence and clinical implications of anti-drug antibody formation and serum drug levels among patients with IBD receiving anti-TNF therapy: A cross-sectional study"],"prefix":"10.4103","volume":"31","author":[{"given":"Ahmed","family":"Alghamdi","sequence":"first","affiliation":[{"name":"Department of Gastroenterology and Hepatology, King Fahad Medical City, Riyadh, Saudi Arabia"},{"name":"Department of Internal Medicine, College of Medicine, Dar Al Uloom University, Riyadh, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mohammed","family":"Alahmari","sequence":"additional","affiliation":[{"name":"Department of Gastroenterology and Hepatology, King Fahad Medical City, Riyadh, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Khulood","family":"Aljohani","sequence":"additional","affiliation":[{"name":"Department of Gastroenterology and Hepatology, King Fahad Medical City, Riyadh, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Aisha","family":"Alanazi","sequence":"additional","affiliation":[{"name":"Department of Gastroenterology and Hepatology, King Fahad Medical City, Riyadh, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bashaar","family":"Al Ibrahim","sequence":"additional","affiliation":[{"name":"Department of Gastroenterology and Hepatology, King Fahad Medical City, Riyadh, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mishal","family":"Alshowair","sequence":"additional","affiliation":[{"name":"Department of Gastroenterology and Hepatology, King Fahad Medical City, Riyadh, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marwa","family":"Tawfik","sequence":"additional","affiliation":[{"name":"Department of Gastroenterology and Hepatology, King Fahad Medical City, Riyadh, Saudi Arabia"},{"name":"Internal Medicine Department, Hepatobiliary Unit, Alexandria Faculty of Medicine, Alexandria University, Alexandria, Egypt"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Waleed","family":"Alghamdi","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine, King Fahad Medical City, Riyadh, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Salman","family":"Alanazi","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine, King Fahad Medical City, Riyadh, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Faisal","family":"Alzayed","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine, King Fahad Medical City, Riyadh, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Abdullah S","family":"Alghamdi","sequence":"additional","affiliation":[{"name":"Department of Gastroenterology and Hepatology, King Fahad Medical City, Riyadh, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Abdullah","family":"Bawazir","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine, King Fahad Medical City, Riyadh, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hussam","family":"Alhamidi","sequence":"additional","affiliation":[{"name":"Department of Gastroenterology and Hepatology, King Fahad Medical City, Riyadh, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"276","published-online":{"date-parts":[[2025,1,23]]},"reference":[{"key":"R1-20250312","doi-asserted-by":"crossref","first-page":"870","DOI":"10.1111\/j.1365-2036.2011.04599.x","article-title":"Review article:Remission rates achievable by current therapies for inflammatory bowel disease","volume":"33","author":"Peyrin-Biroulet","year":"2011","journal-title":"Aliment Pharmacol Ther"},{"key":"R2-20250312","doi-asserted-by":"crossref","first-page":"1464","DOI":"10.1053\/j.gastro.2013.10.046","article-title":"American Gastroenterological Association Institute technical review on the use of thiopurines, methotrexate, and anti\u2013TNF-\u03b1 biologic drugs for the induction and maintenance of remission in inflammatory Crohn's disease","volume":"145","author":"Dassopoulos","year":"2013","journal-title":"Gastroenterology"},{"key":"R3-20250312","doi-asserted-by":"crossref","first-page":"28","DOI":"10.1016\/j.crohns.2009.12.002","article-title":"The second European evidence-based consensus on the diagnosis and management of Crohn's disease:Current management","volume":"4","author":"Dignass","year":"2010","journal-title":"J Crohns Colitis"},{"key":"R4-20250312","doi-asserted-by":"crossref","first-page":"210","DOI":"10.4103\/sjg.SJG_41_20","article-title":"Risk of neutropenia in inflammatory bowel disease patients treated with TNF inhibitors:A single-center, retrospective cohort study","volume":"26","author":"AlAskar","year":"2020","journal-title":"Saudi J Gastroenterol"},{"key":"R5-20250312","doi-asserted-by":"crossref","first-page":"1349","DOI":"10.1111\/apt.12749","article-title":"Systematic review with network meta-analysis:The efficacy of anti-TNF agents for the treatment of Crohn's disease","volume":"39","author":"Stidham","year":"2014","journal-title":"Aliment Pharmacol Ther"},{"key":"R6-20250312","first-page":"63","article-title":"Biologics in the management of ulcerative colitis \u2013comparative safety and efficacy of TNF-\u03b1 antagonists","volume":"11","author":"Fausel","year":"2015","journal-title":"Ther Clin Risk Manag"},{"key":"R7-20250312","doi-asserted-by":"crossref","first-page":"85","DOI":"10.1053\/j.gastro.2013.05.048","article-title":"Subcutaneous golimumab induces clinical response and remission in patients with moderate-to-severe ulcerative colitis","volume":"146","author":"Sandborn","year":"2014","journal-title":"Gastroenterology"},{"key":"R8-20250312","doi-asserted-by":"crossref","first-page":"96","DOI":"10.1053\/j.gastro.2013.06.010","article-title":"Subcutaneous golimumab maintains clinical response in patients with moderate-to-severe ulcerative colitis","volume":"146","author":"Sandborn","year":"2014","journal-title":"Gastroenterology"},{"key":"R9-20250312","doi-asserted-by":"crossref","first-page":"127","DOI":"10.1016\/j.gastrohep.2013.01.002","article-title":"Recommendations of the Spanish Working Group on Crohn's Disease and Ulcerative Colitis on the use of anti-tumor necrosis factor drugs in inflammatory bowel disease","volume":"36","author":"Cabriada","year":"2013","journal-title":"Gastroenterol Hepatol"},{"key":"R10-20250312","doi-asserted-by":"crossref","first-page":"265","DOI":"10.1016\/j.gastrohep.2015.09.012","article-title":"Drugs and antidrug antibody levels in the management of patients with inflammatory bowel disease","volume":"39","author":"L\u00f3pez-Ib\u00e1\u00f1ez","year":"2016","journal-title":"Gastroenterol Hepatol"},{"key":"R11-20250312","doi-asserted-by":"crossref","first-page":"987","DOI":"10.1111\/j.1365-2036.2011.04612.x","article-title":"Review article:loss of response to anti-TNF treatments in Crohn's disease","volume":"33","author":"Ben-Horin","year":"2011","journal-title":"Aliment Pharmacol Ther"},{"key":"R12-20250312","doi-asserted-by":"crossref","first-page":"674","DOI":"10.1038\/ajg.2011.60","article-title":"Loss of response and need for adalimumab dose intensification in Crohn's disease:A systematic review","volume":"106","author":"Billioud","year":"2011","journal-title":"Am J Gastroenterol"},{"key":"R13-20250312","first-page":"760","article-title":"Loss of response and requirement of infliximab dose intensification in Crohn's disease:A review","volume":"104","author":"Gisbert","year":"2009","journal-title":"Am J Gastroenterol"},{"key":"R14-20250312","doi-asserted-by":"crossref","first-page":"675","DOI":"10.1097\/MCG.0000000000000265","article-title":"Outpatient ulcerative colitis primary anti-TNF responders receiving adalimumab or infliximab maintenance therapy have similar rates of secondary loss of response","volume":"49","author":"Ma","year":"2015","journal-title":"J Clin Gastroenterol"},{"key":"R15-20250312","doi-asserted-by":"crossref","first-page":"1133","DOI":"10.1038\/ajg.2010.9","article-title":"Clinical utility of measuring infliximab and human anti-chimeric antibody concentrations in patients with inflammatory bowel disease","volume":"105","author":"Afif","year":"2010","journal-title":"Am J Gastroenterol"},{"key":"R16-20250312","doi-asserted-by":"crossref","first-page":"522","DOI":"10.1016\/j.cgh.2014.07.029","article-title":"Levels of drug and antidrug antibodies are associated with outcome of interventions after loss of response to infliximab or adalimumab","volume":"13","author":"Yanai","year":"2015","journal-title":"Clin Gastroenterol Hepatol"},{"key":"R17-20250312","doi-asserted-by":"crossref","first-page":"189","DOI":"10.1136\/flgastro-2016-100739","article-title":"Utilisation of anti-TNF levels in a UK tertiary IBD centre","volume":"8","author":"Johnston","year":"2017","journal-title":"Frontline Gastroenterol"},{"key":"R18-20250312","doi-asserted-by":"crossref","first-page":"289","DOI":"10.1136\/flgastro-2016-100685","article-title":"Use of anti-TNF drug levels to optimise patient management","volume":"7","author":"Papamichael","year":"2016","journal-title":"Frontline Gastroenterol"},{"key":"R19-20250312","doi-asserted-by":"crossref","first-page":"122","DOI":"10.1136\/flgastro-2014-100527","article-title":"Anti-TNF drug and antidrug antibody level monitoring in IBD:A practical guide","volume":"7","author":"Hendy","year":"2016","journal-title":"Frontline Gastroenterol"},{"key":"R20-20250312","doi-asserted-by":"crossref","first-page":"514","DOI":"10.1016\/j.cgh.2014.07.027","article-title":"Withdrawal of immunomodulators after co-treatment does not reduce trough level of infliximab in patients with Crohn's disease","volume":"13","author":"Drobne","year":"2015","journal-title":"Clin Gastroenterol Hepatol"},{"key":"R21-20250312","doi-asserted-by":"crossref","first-page":"869","DOI":"10.1016\/j.dld.2020.05.031","article-title":"Incidence of suboptimal response to tumor necrosis factor antagonist therapy in inflammatory bowel disease in newly industrialised countries:The EXPLORE study","volume":"52","author":"Yamamoto-Furusho","year":"2020","journal-title":"Dig Liver Dis"},{"key":"R22-20250312","doi-asserted-by":"crossref","first-page":"4157","DOI":"10.3390\/jcm11144157","article-title":"Predictors of anti-TNF therapy failure among inflammatory bowel disease (IBD) patients in Saudi Arabia:A single-center study","volume":"11","author":"Alharbi","year":"2022","journal-title":"J Clin Med"},{"key":"R23-20250312","first-page":"p. 12","author":"von","year":"2008","journal-title":"STROBE Eigen Doc (from Equator)"},{"key":"R24-20250312","doi-asserted-by":"crossref","first-page":"144","DOI":"10.1093\/ecco-jcc\/jjy113","article-title":"ECCO-ESGAR guideline for diagnostic assessment in IBD Part 1:Initial diagnosis, monitoring of known IBD, detection of complications","volume":"13","author":"Maaser","year":"2019","journal-title":"J Crohns Colitis"},{"key":"R27-20250312","doi-asserted-by":"crossref","first-page":"1248","DOI":"10.1016\/j.cgh.2006.06.025","article-title":"Association of trough serum infliximab to clinical outcome after scheduled maintenance treatment for Crohn's disease","volume":"4","author":"Maser","year":"2006","journal-title":"Clin Gastroenterol Hepatol"},{"key":"R28-20250312","doi-asserted-by":"crossref","first-page":"49","DOI":"10.1136\/gut.2009.183095","article-title":"Trough serum infliximab:A predictive factor of clinical outcome for infliximab treatment in acute ulcerative colitis","volume":"59","author":"Seow","year":"2010","journal-title":"Gut"},{"key":"R29-20250312","doi-asserted-by":"crossref","first-page":"1079","DOI":"10.1016\/j.cgh.2012.06.032","article-title":"Therapeutic drug monitoring of tumor necrosis factor antagonists in inflammatory bowel disease","volume":"10","author":"Ord\u00e1s","year":"2012","journal-title":"Clin Gastroenterol Hepatol"},{"key":"R30-20250312","doi-asserted-by":"crossref","first-page":"229","DOI":"10.1136\/gutjnl-2011-300755","article-title":"Switch to adalimumab in patients with Crohn's disease controlled by maintenance infliximab:Prospective randomised SWITCH trial","volume":"61","author":"Van Assche","year":"2012","journal-title":"Gut"},{"key":"R31-20250312","doi-asserted-by":"crossref","first-page":"736","DOI":"10.1016\/j.crohns.2012.10.019","article-title":"Infliximab trough levels may predict sustained response to infliximab in patients with Crohn's disease","volume":"7","author":"Bortlik","year":"2013","journal-title":"J Crohns Colitis"},{"key":"R32-20250312","doi-asserted-by":"crossref","first-page":"1296","DOI":"10.1053\/j.gastro.2014.08.035","article-title":"Association between serum concentration of infliximab and efficacy in adult patients with ulcerative colitis","volume":"147","author":"Adedokun","year":"2014","journal-title":"Gastroenterology"},{"key":"R33-20250312","doi-asserted-by":"crossref","first-page":"1539","DOI":"10.1136\/gutjnl-2014-307883","article-title":"The relationship between infliximab concentrations, antibodies to infliximab and disease activity in Crohn's disease","volume":"64","author":"Vande","year":"2015","journal-title":"Gut"},{"key":"R34-20250312","doi-asserted-by":"crossref","first-page":"1288","DOI":"10.1097\/MIB.0000000000000037","article-title":"Pharmacokinetics of adalimumab in inflammatory bowel diseases:A systematic review and meta-analysis","volume":"20","author":"Paul","year":"2014","journal-title":"Inflamm Bowel Dis"},{"key":"R35-20250312","doi-asserted-by":"crossref","first-page":"601","DOI":"10.1056\/NEJMoa020888","article-title":"Influence of immunogenicity on the long-term efficacy of infliximab in Crohn's disease","volume":"348","author":"Baert","year":"2003","journal-title":"N Engl J Med"},{"key":"R36-20250312","doi-asserted-by":"crossref","first-page":"1078","DOI":"10.1097\/MEG.0b013e32835558cf","article-title":"Anti-infliximab antibodies in inflammatory bowel disease:prevalence, infusion reactions, immunosuppression and response, a meta-analysis","volume":"24","author":"Lee","year":"2012","journal-title":"Eur J Gastroenterol Hepatol"},{"key":"R37-20250312","doi-asserted-by":"crossref","first-page":"1126","DOI":"10.1136\/gutjnl-2014-307882","article-title":"Antibodies to adalimumab are associated with future inflammation in Crohn's patients receiving maintenance adalimumab therapy:A post hoc analysis of the Karmiris trial","volume":"65","author":"Baert","year":"2016","journal-title":"Gut"},{"key":"R38-20250312","doi-asserted-by":"crossref","first-page":"204","DOI":"10.1080\/00365521.2016.1245777","article-title":"Concurrent immunomodulator therapy is associated with higher adalimumab trough levels during scheduled maintenance therapy","volume":"52","author":"Bond","year":"2017","journal-title":"Scand J Gastroenterol"},{"key":"R39-20250312","doi-asserted-by":"crossref","first-page":"1232","DOI":"10.1136\/gut.2006.106781","article-title":"Adalimumab for maintenance treatment of Crohn's disease:Results of the Classic II trial","volume":"56","author":"Sandborn","year":"2007","journal-title":"Gut"},{"key":"R40-20250312","doi-asserted-by":"crossref","first-page":"786","DOI":"10.3390\/v13050786","article-title":"Age, disease severity and ethnicity influence humoral responses in a multi-ethnic COVID-19 cohort","volume":"13","author":"Smith","year":"2021","journal-title":"Viruses"}],"container-title":["Saudi Journal of Gastroenterology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.ovid.com\/10.4103\/sjg.sjg_245_24","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,8,27]],"date-time":"2026-08-27T13:20:09Z","timestamp":1787836809000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.ovid.com\/10.4103\/sjg.sjg_245_24"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,1,23]]},"references-count":38,"journal-issue":{"issue":"2","published-print":{"date-parts":[[2025]]}},"URL":"https:\/\/doi.org\/10.4103\/sjg.sjg_245_24","relation":{},"ISSN":["1319-3767","1998-4049"],"issn-type":[{"value":"1319-3767","type":"print"},{"value":"1998-4049","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,1,23]]},"assertion":[{"value":"2024-07-08","name":"received","label":"Received","group":{"name":"publication_history","label":"Publication History"}},{"value":"2024-12-09","name":"accepted","label":"Accepted","group":{"name":"publication_history","label":"Publication History"}}]}}