Outcome of Biological Therapies and Small Molecules in Ulcerative Proctitis: A Belgian Multicenter Cohort Study.

BACKGROUND & AIMS: Several advanced therapies (biologic therapies and small molecules) have been approved for the treatment of moderate-to-severe ulcerative colitis. The registration trials for these agents typically excluded patients with isolated proctitis, leaving an evidence gap. We evaluated efficacy and safety of advanced therapies in patients with ulcerative proctitis (UP). METHODS: This multicenter retrospective cohort study included consecutive patients with active UP (Mayo endoscopy subscore of ≥2, rectal inflammation up to 15 cm) initiating advanced therapy, after failing conventional therapy. The primary end point was short-term steroid-free clinical remission (total Mayo score ≤2 with no individual subscore >1). In addition, drug persistence and relapse-free and colectomy-free survival were assessed. Both binary logistic and Cox regression analyses were performed. RESULTS: In total, 167 consecutive patients (52.0% female; median age 41.0 years; 82.0% bionaive) underwent 223 courses of therapy for UP (38 adalimumab, 14 golimumab, 54 infliximab, 9 ustekinumab, 99 vedolizumab, 9 tofacitinib). The primary end point was achieved with 36.3% of the treatment courses, and based on multivariate analysis, more commonly attained in bionaive patients (P = .001), patients treated with vedolizumab (P = .001), patients with moderate endoscopic disease activity (P = .002), and a body mass index <25 kg/m2 (P = .018). Drug persistence was significantly higher in patients treated with vedolizumab (P < .001) and patients with a shorter disease duration (P = .006). No new safety signals were observed. CONCLUSIONS: Advanced therapies are also efficacious and safe in patients with ulcerative colitis limited to the rectum. Therefore, the inclusion of patients with UP in future randomized-controlled trials should be considered.

Dysbiosis and Associated Stool Features Improve Prediction of Response to Biological Therapy in Inflammatory Bowel Disease.

BACKGROUND & AIMS: Dysbiosis of the gut microbiota is considered a key contributor to inflammatory bowel disease (IBD) etiology. Here, we investigated potential associations between microbiota composition and the outcomes to biological therapies. METHODS: The study prospectively recruited 296 patients with active IBD (203 with Crohn's disease, 93 with ulcerative colitis) initiating biological therapy. Quantitative microbiome profiles of pretreatment and posttreatment fecal samples were obtained combining flow cytometry with 16S amplicon sequencing. Therapeutic response was assessed by endoscopy, patient-reported outcomes, and changes in fecal calprotectin. The effect of therapy on microbiome variation was evaluated using constrained ordination methods. Prediction of therapy outcome was performed using logistic regression with 5-fold cross-validation. RESULTS: At baseline, 65.9% of patients carried the dysbiotic Bacteroides2 (Bact2) enterotype, with a significantly higher prevalence among patients with ileal involvement (76.8%). Microbiome variation was associated with the choice of biological therapy rather than with therapeutic outcome. Only anti-tumor necrosis factor-α treatment resulted in a microbiome shift away from Bact2, concomitant with an increase in microbial load and butyrogen abundances and a decrease in potentially opportunistic Veillonella. Remission rates for patients hosting Bact2 at baseline were significantly higher with anti-tumor necrosis factor-α than with vedolizumab (65.1% vs 35.2%). A prediction model, based on anthropometrics and clinical data, stool features (microbial load, moisture, and calprotectin), and Bact2 detection predicted treatment outcome with 73.9% accuracy for specific biological therapies. CONCLUSION: Fecal characterization based on microbial load, moisture content, calprotectin concentration, and enterotyping may aid in the therapeutic choice of biological therapy in IBD.

Vedolizumab for the Treatment of Chronic Pouchitis.

BACKGROUND: Approximately half the patients with ulcerative colitis who undergo restorative proctocolectomy with ileal pouch-anal anastomosis (IPAA) will subsequently have pouchitis, and among those patients, one fifth will have chronic pouchitis. METHODS: We conducted a phase 4, double-blind, randomized trial to evaluate vedolizumab in adult patients in whom chronic pouchitis had developed after undergoing IPAA for ulcerative colitis. Patients were assigned (in a 1:1 ratio) to receive vedolizumab intravenously at a dose of 300 mg or placebo on day 1 and at weeks 2, 6, 14, 22, and 30. All the patients received concomitant ciprofloxacin from weeks 1 to 4. The primary end point was modified Pouchitis Disease Activity Index (mPDAI)-defined remission (an mPDAI score of ≤4 and a reduction from baseline of ≥2 points in the mPDAI total score; scores range from 0 to 12, with higher scores indicating more severe pouchitis) at week 14. The mPDAI is based on clinical symptoms and endoscopic findings. Other efficacy end points included mPDAI-defined remission at week 34, mPDAI-defined response (a reduction from baseline of ≥2 points in the mPDAI score) at weeks 14 and 34, and PDAI-defined remission (a PDAI score of ≤6 and a reduction from baseline of ≥3 points; scores range from 0 to 18, with higher scores indicating more severe pouchitis) at weeks 14 and 34. The PDAI is based on clinical symptoms, endoscopic findings, and histologic findings. RESULTS: Among the 102 patients who underwent randomization, the incidence of mPDAI-defined remission at week 14 was 31% (16 of 51 patients) with vedolizumab and 10% (5 of 51 patients) with placebo (difference, 21 percentage points; 95% confidence interval [CI], 5 to 38; P = 0.01). Differences in favor of vedolizumab over placebo were also seen with respect to mPDAI-defined remission at week 34 (difference, 17 percentage points; 95% CI, 0 to 35), mPDAI-defined response at week 14 (difference, 30 percentage points; 95% CI, 8 to 48) and at week 34 (difference, 22 percentage points; 95% CI, 2 to 40), and PDAI-defined remission at week 14 (difference, 25 percentage points; 95% CI, 8 to 41) and at week 34 (difference, 19 percentage points; 95% CI, 2 to 37). Serious adverse events occurred in 3 of 51 patients (6%) in the vedolizumab group and in 4 of 51 patients (8%) in the placebo group. CONCLUSIONS: Treatment with vedolizumab was more effective than placebo in inducing remission in patients who had chronic pouchitis after undergoing IPAA for ulcerative colitis. (Funded by Takeda; EARNEST ClinicalTrials.gov number, NCT02790138; EudraCT number, 2015-003472-78.).

Holistic healthcare in inflammatory bowel disease: time for patient-centric approaches?

Inflammatory bowel disease (IBD) is an emerging global disease characterised by chronic inflammation of the gastrointestinal tract. However, IBD is also manifested by several extraintestinal symptoms which, along with the intestinal symptoms, impact on the mental and emotional well-being of patients. Despite therapeutic advancements, only one-third of the diagnosed patients receiving approved medical treatments achieve short-term to medium-term remission. Consequently, patients who do not get successfully treated might resort to using complementary and alternative approaches to manage their symptoms, with or without consulting their treating clinician. Despite their possible potential, such approaches have various risks stemming from unknown adverse reactions and possible interference with medically approved therapies. In this study, we present the results of a well-performed literature review where we included randomised clinical trials which have assessed the efficacy of complementary approaches and dietary therapy on at least one of the following four outcomes: clinical remission, endoscopic remission, modulation of molecular biomarkers or quality of life metrics. By pointing out intraoutcome and interoutcome concordance, we identified possible candidates for clinical adoption and further study in larger randomised clinical trials covering the broad spectrum of IBD heterogeneity. We finally proposed a patient-centric clinical care model and a series of recommendations for stakeholders, with special attention to complementary approaches and dietary strategies, aimed at achieving holistic remission.

Safety of sequential biological therapy in inflammatory bowel disease: results from a tertiary referral centre.

BACKGROUND: Biologicals represent the cornerstone of treatment for moderate-to-severe inflammatory bowel diseases (IBD). Many patients cycle between biologicals when encountering loss of response or adverse events. AIM: To assess the occurrence of serious infections and malignancies with exposure to several (classes of) biologicals. METHODS: We performed a retrospective cohort study in a tertiary referral centre including consecutive IBD patients exposed to adalimumab, infliximab, ustekinumab or vedolizumab between 1996 and 2019. All serious infections and malignancies, as well as potential confounders, were accounted for. RESULTS: In total, 1575 patients were included with a median (interquartile range) follow-up of 10 (6-16) years and a duration of biological therapy of 71 (39-112) months. Incidence rates of serious infections were 3.4 per 100 patients' years (PY) in the post-biological setting. Serious infections after biological exposure were associated with systemic steroids in monotherapy (hazard ratio 2.96 [95% confidence interval 1.78-4.93], p < 0.0001), combination therapy of systemic steroids and a biological (2.44 [1.37-4.34], p = 0.002), female gender (1.25 [1.04-1.51], p = 0.02), and prior serious infections in the pre-biological setting (1.42 [1.03-1.96], p = 0.03). Malignancy rates were 1.06 per 100PY in the post-biological setting and increased with older age at biological initiation (1.04 [1.02-1.05], p < 0.0001). The risk for serious infections or malignancies was independent of type and number of biologicals to which the patient was exposed. CONCLUSION: This study shows that the sequential use of biological therapy in IBD does not seem to convey an overall higher risk of serious infections or malignancies, but that underlying more refractory disease seems to increase this risk.

Early Reduction in MM-SES-CD Score After Initiation of Biologic Therapy is Highly Specific for 1-year Endoscopic Remission in Moderate to Severe Crohn's Disease.

BACKGROUND AND AIMS: This study evaluated the minimal clinically important short-term improvement in the Modified Multiplier Simple Endoscopic Score for crohn's Disease [MM-SES-CD], a novel modified scoring system of the SES-CD, which reliably predicted 1-year endoscopic remission [ER]. METHODS: This post-hoc analysis of two CD clinical trial programmes pooled data of 198 participants with baseline ulcers and SES-CD ≥3, who had baseline, post-induction [8-12 weeks], and 1-year endoscopic assessments. Different cut-off values for endoscopic response were evaluated using receiver operating characteristic [ROC] curves, positive likelihood ratios [PLR], and negative likelihood ratios [NLR]. ER [SES-CD <3] was the binary classifier in all cases. A distribution of cut-offs minimising NLR and maximising PLR was created with 10 000 bootstrapped resamples. An optimal cut-point for low and high probability of 1-year ER was determined based on the maximum Youden Index. RESULTS: MM-SES-CD ≥40% reduction from baseline was selected as the cut-off maximising PLR and minimising NLR. Among 7.6% [15/198] participants achieving this cut-off post-induction, 1-year ER was 46.7%. One-year ER was 16.9% among those not achieving this cut-off. This threshold predicted 1-year ER with 95.0% (95% confidence interval [CI] 90.4%-97.8%) specificity and a PLR of 3.7 [95% CI 1.4-9.5], which was higher than traditional endoscopic response criteria of SES-CD ≥50% reduction [specificity 62.5%, 95% CI 54.5%-70.0%; PLR 1.9, 95% CI 1.4-2.5]. Lower thresholds of MM-SES-CD reduction also were highly specific for 1-year ER [e.g., MM-SES-CD ≥20% reduction was achieved in 19.7% of patients with 83.1% specificity]. CONCLUSIONS: In CD patients, post-induction endoscopic response defined by MM-SES-CD ≥40% reduction from baseline identified patients most likely to achieve 1-year ER.

Rates of Postoperative Recurrence of Crohn's Disease and Effects of Immunosuppressive and Biologic Therapies.

BACKGROUND & AIMS: The Rutgeerts' scoring system is used to evaluate patients with Crohn's disease (CD) following ileocolic resection, based on endoscopic findings at the anastomosis and in the neoterminal ileum. We investigated rates of clinical and surgical recurrence of CD after surgery and effect of therapy modification based on post-operative endoscopic findings. METHODS: We collected data from 365 adults with CD (20% with Rutgeerts' score i0, 10% with score i1, 49% with score i2, 12% with score i3, 9% with score i4) who underwent ileocolonoscopy within 12 months of ileocolic resection with anastomosis from 2000 through 2013 at 2 centers in Belgium and France. Patients were followed for 3 y or more after the ileocolonoscopy. Clinical post-operative recurrence (POR) was defined as occurrence of CD symptoms along with biologic, radiologic, and/or endoscopic features of disease activity; modified surgical POR was defined as either an endoscopic or surgical intervention. RESULTS: After a median follow-up time of 88 months, 48% of patients had clinical POR and 26% had modified surgical POR. Rates of survival without clinical POR or a modified surgical POR were lower in patients with Rutgeerts' scores of i2, i3, or i4 compared to patients with scores of i0 or i1 (P < .001 and P = .02). New immunosuppressant or biological therapy was initiated following endoscopy in 129/254 patients (51%) with Rutgeerts' score of i2, i3, or i4 vs 7/111 patients (6%) with scores of i0 or i1 (odds ratio for new therapy, 14.9; 95% CI, 7.1-36.8; P < .001). A modest decrease in risk of clinical POR was observed for patients with Rutgeerts scores of i3 or i4 after initiation of immunosuppressive or biological therapy based on endoscopic findings (Breslow P = .03), but this was not observed for patients with scores of i2 (Breslow P = .46). CONCLUSIONS: Use of immunosuppressants and tumor necrosis factor antagonists to treat patients with an asymptomatic endoscopic post-operative recurrence of CD did not reduce long-term risk of clinical recurrence in patients with Rutgeerts' scores of i2, but it had a small effect in patients with scores of i3 or i4.

High-Dose Vitamin D Does Not Prevent Postoperative Recurrence of Crohn's Disease in a Randomized Placebo-Controlled Trial.

BACKGROUND & AIMS: Vitamin D deficiency is common in Crohn's disease (CD). High-dose vitamin D had anti-inflammatory effects in preclinical studies and trials of patients with CD. We performed a randomized trial to determine whether high-dose vitamin D prevents postoperative recurrence of CD after ileocolonic resection. METHODS: Patients with CD after ileocolonic resection with ileocolonic anastomosis were assigned randomly to groups given weekly 25,000 IU oral vitamin D (n = 72) or placebo (n = 71) for 26 weeks, at 17 hospitals in The Netherlands and Belgium, from February 2014 through June 2017. Patients were assessed at baseline and at weeks 2, 6, 12, and 26 for laboratory and clinical parameters, and underwent ileocolonoscopy at 26 weeks. The primary end point was endoscopic recurrence (modified Rutgeerts score, ≥i2b, as assessed by blinded readers) at 26 weeks. Secondary end points included clinical recurrence (Crohn's disease activity index, ≥220), quality of life (measured by the 36-Item Short Form Health Survey, Inflammatory Bowel Disease Questionnaire, and EuroQol, a 5-dimension questionnaire), and outcomes associated with the baseline serum concentration of vitamin D. RESULTS: In the vitamin D group, serum levels of 25-hydroxy vitamin D increased from a median of 42 nmol/L at baseline to 81 nmol/L at week 26 (P < .00001), whereas levels did not change significantly in the placebo group and remained unchanged at 43 nmol/L. In the intention-to-treat analysis, the proportion of patients with endoscopic recurrence at 26 weeks did not differ significantly between the vitamin D vs the placebo group (58% vs 66%; P = .37). The cumulative rate of clinical recurrence did not differ significantly between the groups (18.1% in the vitamin D group vs 18.3% in the placebo group; P = .91). Quality of life improved slightly over time in both groups, but did not differ significantly between groups (P = .07). There were few adverse events in either group. CONCLUSIONS: High-dose vitamin D, compared with placebo, did not reduce the incidence of postoperative endoscopic or clinical recurrence of CD in patients who underwent ileocolonic resection with ileocolonic anastomosis. ClinicalTrials.gov no: NCT02010762.

Gastroenterologists' preference and risk perception on the use of immunomodulators and biological therapies in elderly patients with ulcerative colitis: an international survey.

BACKGROUND AND AIMS: Comorbidities, polypharmacy, malignancies, and infections complicate management of elderly patients with inflammatory bowel diseases (IBD). This study assessed gastroenterologists' preference in the prescription of medications or surgery to elderly patients with IBD, and the factors associated with their choices. METHODS: An international case-based survey was conducted that presented three cases of steroid-dependent ulcerative colitis assessing young-age versus elderly-age patients, with and without comorbidity. Physician characteristics and practice demographics were collected. Factors associated with selection of different choices of therapy were determined by logistic regression analysis. RESULTS: A total of 424 respondents from 41 countries were included. Vedolizumab (53.2%) and thiopurines (19.4%) were the top treatment preferences for moderate-to-severe ulcerative colitis (P < 0.0001). Comorbidity and older age were independently associated with more frequent use of vedolizumab (P < 0.0001), and less frequent use of immunomodulators and anti-tumour necrosis factor (TNF; P < 0.0001). Comorbidity was the only independent predictor for selecting colectomy (P < 0.0001). A history of lymphoma (94%) and opportunistic infection (78.3%) were the most frequent conditions precluding the use of thiopurine and anti-TNF in elderly patients with IBD. Only 6.1% of respondents considered patient age a limit for vedolizumab, while 37.9% considered age as a limiting factor in prescribing thiopurines (P < 0.001). Geographical heterogeneity was identified with significantly more physicians from Oceania and North America favouring the use of vedolizumab. CONCLUSION: Vedolizumab was the preferred first-line agent in the treatment of elderly patients with IBD with steroid-dependent moderate-to-severe ulcerative colitis. Older age and presence of comorbidity influenced the selection of medication. Comorbidity was the main predictor of colectomy. Geographical heterogeneity in prescribing habits may relate to medication reimbursement in individual countries.

Development and feasibility of a telemonitoring tool with full integration in the electronic medical record: a proof of concept study for patients with inflammatory bowel disease in remission on biological therapy.

Objectives: Telemonitoring can be implemented to enhance disease monitoring and ultimately reduce the number of outpatient visits and associated costs. We developed an in house IBD mobile app and established a proof of concept study to demonstrate the effectiveness and accuracy of the telemonitoring tool for monitoring of disease activity.Methods: An IBD mobile app was designed through close collaboration between the Information Technology and Gastroenterology department of University Hospitals of Leuven. The study was proposed to all patients in remission under stable biological therapy visiting the outpatient clinic. During one-year follow-up, patients completed weekly and monthly questionnaires on their mobile device or on a website. Entered data were directly sent to the electronic medical record. Predefined red flags or alerts, generated by the answers to the questionnaires, were monitored daily.Results: The pilot study in 45 patients demonstrated accurate monitoring of disease activity with fast intervention during flares. During the 12-months follow-up period, an alert for disease activity was generated for 9 different patients out of 1296 completions of the questionnaire. Symptoms resolved spontaneously in 8 patients. One patient reported consecutive PRO-2 increase, endoscopy confirmed an IBD flare and therapy was switched. For the remaining 36 included patients, no alerts indicating disease activity increase were reported. Median compliance to all weekly and monthly questionnaires during 1 year was 52% (IQR: 24-91).Conclusions: We developed the mynexuzhealth IBD app with full integration in the electronic medical record. The app enabled continuous remote monitoring and showed accurate detection of flares.

Patient-derived organoids from endometrial disease capture clinical heterogeneity and are amenable to drug screening.

Endometrial disorders represent a major gynaecological burden. Current research models fail to recapitulate the nature and heterogeneity of these diseases, thereby hampering scientific and clinical progress. Here we developed long-term expandable organoids from a broad spectrum of endometrial pathologies. Organoids from endometriosis show disease-associated traits and cancer-linked mutations. Endometrial cancer-derived organoids accurately capture cancer subtypes, replicate the mutational landscape of the tumours and display patient-specific drug responses. Organoids were also established from precancerous pathologies encompassing endometrial hyperplasia and Lynch syndrome, and inherited gene mutations were maintained. Endometrial disease organoids reproduced the original lesion when transplanted in vivo. In summary, we developed multiple organoid models that capture endometrial disease diversity and will provide powerful research models and drug screening and discovery tools.

Effects of introduction of an inflammatory bowel disease nurse position on the quality of delivered care.

BACKGROUND AND AIMS: Inflammatory bowel diseases (IBDs) are chronic gastrointestinal conditions requiring long-term outpatient follow-up, ideally by a dedicated, multidisciplinary team. In this team, the IBD nurse is the key point of access for education, advice, and support. We investigated the effect of the introduction of an IBD nurse on the quality of care delivered. METHODS: In September 2014, an IBD nurse position was instituted in our tertiary referral center. All contacts and outcomes were prospectively recorded over a 12-month period using a logbook kept by the nurse. RESULTS: Between September 2014 and August 2015, 1313 patient contacts were recorded (42% men, median age: 38 years, 72% Crohn's disease, 83% on immunosuppressive therapy). The contacts increased with time: Q1 (September-November 2014): 144, Q2: 322, Q3: 477, and Q4: 370. Most of the contacts were assigned to scheduling of follow-up (316/1420), start of new therapy (173/1420), therapy follow-up (313/1420), and providing disease information (227/1420). In addition, 134 patients contacted the IBD nurse for flare management and a smaller number for administrative support, psychosocial support, and questions about side effects. During the study period, 30 emergency room and 133 unscheduled outpatient visits could be avoided through the intervention of the IBD nurse. A faster access to procedures and other departments could be provided for 136 patients. CONCLUSION: The role of IBD nurses as the first point of contact and counseling is evident from a high volume of nurse-patient interactions. Avoidance of emergency room and unscheduled clinic visits are associated with these contacts.

Biological therapy targeting the IL-23/IL-17 axis in inflammatory bowel disease.

INTRODUCTION: As many inflammatory bowel disease (IBD) patients do not benefit from long-term anti-tumour necrosis factor treatment, new anti-inflammatories are urgently needed. After the discovery of the interleukin (IL) 23/17 axis being pivotal in IBD pathogenesis, many different compounds were developed, targeting different components within this pathway. Areas covered: A literature search to March 2016 was performed to identify the most relevant reports on the role of the IL-23/IL-17 axis in IBD and on the different molecules targeting this pathway. First, the authors briefly summarize the immunology of the IL-23/IL-17 pathway to elucidate the mode of action of all different agents. Second, they describe all different molecules targeting this pathway. Besides discussing efficacy and safety data, they also explore immunogenicity, exposure during pregnancy and pharmacokinetics. Expert opinion: A new era in IBD treatment has recently been initiated: besides immunomodulators and TNF-antagonists, anti-adhesion molecules and monoclonal antibodies targeting the IL-23/IL-17 pathway have been developed. Biomarkers for personalized medicine are urgently needed. This therapeutic (r)evolution will further improve disease-related and patient-reported outcome, though a lot of questions should still be addressed in future years.

rAAV-CFTRΔR Rescues the Cystic Fibrosis Phenotype in Human Intestinal Organoids and Cystic Fibrosis Mice.

RATIONALE: Gene therapy holds promise for a curative mutation-independent treatment applicable to all patients with cystic fibrosis (CF). The various viral vector-based clinical trials conducted in the past have demonstrated safety and tolerance of different vectors, but none have led to a clear and persistent clinical benefit. Recent clinical breakthroughs in recombinant adeno-associated viral vector (rAAV)-based gene therapy encouraged us to reexplore an rAAV approach for CF. OBJECTIVES: We evaluated the preclinical potential of rAAV gene therapy for CF to restore chloride and fluid secretion in two complementary models: intestinal organoids derived from subjects with CF and a CF mouse model, an important milestone toward the development of a clinical rAAV candidate for CF gene therapy. METHODS: We engineered an rAAV vector containing a truncated CF transmembrane conductance regulator (CFTRΔR) combined with a short promoter (CMV173) to ensure optimal gene expression. A rescue in chloride and fluid secretion after rAAV-CFTRΔR treatment was assessed by forskolin-induced swelling in CF transmembrane conductance regulator (CFTR)-deficient organoids and by nasal potential differences in ΔF508 mice. MEASUREMENTS AND MAIN RESULTS: rAAV-CFTRΔR transduction of human CFTR-deficient organoids resulted in forskolin-induced swelling, indicating a restoration of CFTR function. Nasal potential differences demonstrated a clear response to low chloride and forskolin perfusion in most rAAV-CFTRΔR-treated CF mice. CONCLUSIONS: Our study provides robust evidence that rAAV-mediated gene transfer of a truncated CFTR functionally rescues the CF phenotype across the nasal mucosa of CF mice and in patient-derived organoids. These results underscore the clinical potential of rAAV-CFTRΔR in offering a cure for all patients with CF in the future.

Optimizing biologic therapies for inflammatory bowel disease (ulcerative colitis and Crohn's disease).

The introduction of biologic agents and particularly of anti-tumor necrosis factor antibodies dramatically changed the therapeutic algorithm in patients with inflammatory bowel diseases. Although the efficacy of these agents has been demonstrated clearly, optimal treatment strategies are debated. Recent trials advocate the introduction of biologic agents at an early stage to prevent debilitating complications. However, significant adverse events have led to careful selection of patients who will benefit most from long-term treatment with biologic agents. Once on biologic therapy, scheduled maintenance therapy is recommended to minimize the risk of loss of response. Nevertheless, treatment adaptation is frequently necessary in patients who lose response. Interventions encompass strategies to increase drug exposure by increasing the dose or decreasing the dosing interval, or by changing to another biologic agent. Finally, it remains unclear if and when a biologic agent can be stopped in patients with long-standing remission.