Risankizumab: Mechanism of action, clinical and translational science.

Risankizumab is a high-affinity neutralizing anti-interleukin (IL)-23 monoclonal antibody marketed in over 40 countries across the globe to treat several inflammatory diseases, such as plaque psoriasis (PsO), psoriatic arthritis (PsA), and Crohn's disease (CD). This paper reviews the regulatory approval, mechanism of action, pharmacokinetics (PKs)/pharmacodynamics, immunogenicity, and clinical efficacy and safety data for risankizumab, focusing on the three main approved indications. Risankizumab binds to the p19 subunit of IL-23 and inhibits IL-23 from interacting with the IL-23 receptor and subsequent signaling. Biomarker data obtained following treatment with risankizumab in multiple indications provided supportive evidence for downstream blockade of IL-23 signaling associated with disease pathology. The PKs of risankizumab is linear and time-independent, consistent with typical IgG1 monoclonal antibodies, across all evaluated indications. Risankizumab exhibited positive exposure-response relationships for efficacy with no apparent exposure-dependent worsening in safety. Immunogenicity to risankizumab had no major clinical consequences for either efficacy or safety. Efficacy and safety of risankizumab have been established in PsO, PsA, and CD in the pivotal clinical trials where superior benefit/risk profiles were demonstrated compared to placebo and/or active comparators. Moreover, safety evaluations in open-label extension studies following long-term treatment with risankizumab showed stable and favorable safety profiles consistent with shorter-term studies. These data formed the foundation for risankizumab's marketing approvals to treat multiple inflammatory diseases across the globe.

Clinical Bridging From Prefilled Syringe to On-body Injector for Risankizumab in Crohn's Disease.

PURPOSE: This article describes the clinical development bridging strategy and key data to support the marketing application of the risankizumab on-body injection (OBI) system for the treatment of moderately to severely active Crohn's disease (CD), even though the OBI was not evaluated directly in the pivotal Phase III studies in CD. METHODS: Three studies were conducted as part of the clinical bridging strategy. The pilot pharmacokinetics (PK) study was a Phase I, single-dose, 4-arm, open-label, randomized, parallel-group exploratory PK and tolerability study that assessed the effect of rate and volume of administration on the bioavailability (BA) of risankizumab and the extent of injection site-related pain after subcutaneous (SC) administration in healthy subjects. The pivotal BA/bioequivalence (BE) study was a relative BA/BE bridging study in healthy subjects to assess the relative BA of the to-be-marketed risankizumab OBI compared with the prefilled syringe (PFS) used in the Phase III CD studies. The OBI adhesive study was a randomized, open-label, non-drug interventional study in healthy subjects to assess the OBI adhesive effectiveness and skin tolerability at 2 different locations (abdomen and upper thigh) over different periods of time (5 and 30 minutes). FINDINGS: The pilot PK study showed that risankizumab exposures were similar across different rates/volumes of SC administration in healthy subjects, thereby supporting further development of the OBI. Second, a pivotal BA/BE study showed comparability between the OBI and Phase III PFS with bioequivalent risankizumab AUCs and no clinically meaningful difference for Cmax based on the wide therapeutic window of risankizumab. In both studies, no new safety risks were identified. No impact of immunogenicity on PK profile or safety was observed for the OBI. Third, an adhesive OBI (without risankizumab) study showed that there were no differences in adhesion/skin tolerability observed over time (up to 30 minutes) or for location of adhesion, and the OBI device adhesion was well tolerated at both the abdomen and thigh locations. IMPLICATIONS: These results supported the risankizumab OBI presentation approval in CD.

Maintenance Risankizumab Sustains Induction Response in Patients with Crohn's Disease in a Randomized Phase 3 Trial.

BACKGROUND AND AIMS: Durable clinical remission, endoscopic healing, and biomarker normalization are key treatment goals for Crohn's disease. The selective anti-interleukin-23 p19 inhibitor risankizumab has demonstrated efficacy and safety in moderately to severely active Crohn's disease. This post-hoc analysis of data from the pivotal risankizumab maintenance study assessed whether risankizumab maintenance therapy sustained the clinical and endoscopic outcomes achieved with risankizumab induction therapy. METHODS: We evaluated 462 patients who achieved a clinical response to risankizumab intravenous induction treatment and were re-randomized to receive subcutaneous risankizumab 360 mg, subcutaneous risankizumab 180 mg, or placebo [withdrawal] every 8 weeks for 52 weeks in the randomized, controlled FORTIFY maintenance study. Maintenance of clinical, endoscopic, and biomarker endpoints at week 52 among patients who achieved these endpoints after 12 weeks of induction treatment was evaluated. RESULTS: A significantly higher proportion of patients receiving maintenance treatment with risankizumab 360 or 180 mg compared with placebo [withdrawal] maintained Crohn's Disease Activity Index remission [68.6%, 70.8%, vs 56.3%; p < 0.05], stool frequency/abdominal pain remission [69.2%, 64.1%, vs 50.5%; p < 0.01], endoscopic response [70.2%, 68.2%, vs 38.4%; p < 0.001], endoscopic remission [74.4%, 45.5%, vs 23.9%; p < 0.05], and Simple Endoscopic Score for Crohn's Disease of 0-2 [65.5%, 36.7%, vs 21.9%]. Most patients [56.8-83.3%] who achieved normalized faecal calprotectin or C-reactive protein during induction sustained them with maintenance risankizumab. CONCLUSIONS: Subcutaneous risankizumab maintenance therapy results in durable improvement in clinical and endoscopic outcomes over 1 year in patients with moderately to severely active Crohn's disease. CLINICAL TRIAL REGISTRATION NUMBER: NCT03105102.

Content Validity and Psychometric Evaluation of the Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-Fatigue) in Patients with Crohn's Disease and Ulcerative Colitis.

BACKGROUND: Patients with Crohn's disease (CD) or ulcerative colitis (UC) frequently experience fatigue, although it is often overlooked in medical research and practice. AIMS: To explore patients' experience of fatigue and evaluate content validity, psychometric properties, and score interpretability of the Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-Fatigue) in patients with CD or UC. METHODS: Concept elicitation and cognitive interviews were conducted with participants aged ≥ 15 years with moderately-to-severely active CD (N = 30) or UC (N = 33). To evaluate psychometric properties (reliability and construct validity) and interpretation of FACIT-Fatigue scores, data from two clinical trials were analyzed [ADVANCE (CD): N = 850; U-ACHIEVE (UC): 248]. Meaningful within-person change was estimated using anchor-based methods. RESULTS: Almost all interview participants reported experiencing fatigue. Over 30 unique fatigue-related impacts were reported per condition. The FACIT-Fatigue was interpretable for most patients. FACIT-Fatigue items had good internal consistency (Cronbach's α 0.86-0.88 for CD and 0.94-0.96 for UC); the total score displayed acceptable test-retest reliability (intraclass correlation coefficients > 0.60 for CD and > 0.90 for UC). FACIT-Fatigue scores had acceptable convergent validity with similar measures. A 7-10 point improvement for CD and 4-9 point improvement for UC on the FACIT-Fatigue total score may represent meaningful improvements. CONCLUSIONS: These results highlight the importance of fatigue among adolescents and adults with CD or UC and provide evidence that the FACIT-Fatigue is content valid and produces reliable, valid, and interpretable scores in these populations. Care should be taken if using the questionnaire with adolescents who may be less familiar with the word "fatigue." Clinical trial registration numbers NCT03105128 (date of registration: 4 April 2017) and NCT02819635 (date of registration: 28 June 2016).

Efficacy, Safety, Patient Experience, and Tolerability of Risankizumab Administered by On-Body Injector for Moderate to Severe Crohn's Disease.

INTRODUCTION: In patients with moderate to severe Crohn's disease (CD), intravenous induction and subcutaneous maintenance dosing with risankizumab was efficacious and well tolerated. Long-term management of CD via self-administration of risankizumab using an on-body injector (OBI) may improve treatment adherence through convenience and ease of use. METHODS: Within the FORTIFY maintenance study, 46 patients from the United States (US) sites participated in an open-label extension Substudy and received 180 mg or 360 mg risankizumab delivered subcutaneously via OBI [360 mg (2.4 mL, 150 mg/mL) or 180 mg (1.2 mL, 150 mg/mL)]. At the Week 0 visit, patients were trained (pre-injection) by site staff, using Instructions for Use (IFU) and a training video, to self-administer risankizumab at Weeks 0 (on site), 8 (at home), and 16 (on site). Key objectives of the Substudy 4 were to assess OBI usability (observer rating of successful self-administration), hazard-free self-injection at Weeks 0 and 16, and patient rating of acceptability using the Self-Injection Assessment Questionnaire (SIAQ) at Weeks 0, 8, and 16. Additionally, the proportion of patients in clinical remission (CD Activity Index < 150) was collected at Weeks 0 and 16. RESULTS: All patients successfully self-administered risankizumab via OBI, including two patients who successfully self-administered with a second OBI (i.e., required two injection attempts). Acceptability of self-injection was high. Two patients (n = 2) experienced a use-related hazard. Stable clinical remission was observed with both risankizumab doses. Two patients experienced injection site reactions; neither was related to the OBI per investigator's assessment. Two device-related adverse events related to topical adhesive reactions were reported, both mild and resolved. No new safety risks were observed. CONCLUSION: The efficacy and safety of maintenance risankizumab delivered via OBI and OBI usability support the use of this device in patients with moderate to severe CD. TRIAL REGISTRATION: ClinicalTrials.gov identifiers NCT03105102 (FORTIFY).

Effect of risankizumab on health-related quality of life in patients with Crohn's disease: results from phase 3 MOTIVATE, ADVANCE and FORTIFY clinical trials.

BACKGROUND: Crohn's disease has a substantial negative impact on health-related quality of life (HRQoL). AIM: To examine the effects of risankizumab on HRQoL in Crohn's disease METHODS: We analysed data from patients with Crohn's disease from 12-week induction trials ADVANCE (N = 850) and MOTIVATE (N = 569) with risankizumab 600 mg or 1200 mg intravenous (IV) versus placebo IV and a 52-week maintenance trial FORTIFY (N = 462) with risankizumab 180 or 360 mg subcutaneous (SC) versus placebo SC. Outcomes included Inflammatory Bowel Disease Questionnaire (IBDQ), Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-F), 36-item Short Form Health Survey (SF-36), EuroQol 5-Dimension-5-Level (EQ-5D-5L) and work productivity. The mean change and percentages of patients achieving clinically meaningful improvement in all outcomes were determined at weeks 12 and 52. RESULTS: At week 12, more patients in the risankizumab 600 or 1200 mg groups achieved IBDQ response than with placebo (ADVANCE: 70.2%, 75.5% vs. 47.8%, p ≤ 0.001; MOTIVATE: 61.7%, 68.5% vs. 48.2%, p ≤ 0.01) and FACIT-F response (ADVANCE: 51.3%, 48.0% vs. 35.7%, p ≤ 0.01; MOTIVATE: 44.2%, 49.1% vs. 33.7%, p < 0.05). These improvements persisted at week 52 with risankizumab maintenance treatment. Similar trends were observed for SF-36 physical and mental component summary scores, EQ-5D-5L and activity impairment within work productivity measures. CONCLUSIONS: Risankizumab induction therapy (600 or 1200 mg IV) led to clinically meaningful improvements in disease-specific and general patient-reported outcomes, including fatigue, in patients with moderate to severe Crohn's disease. These improvements were sustained after 52 weeks of risankizumab (180 or 360 mg SC) maintenance therapy.

Risankizumab as maintenance therapy for moderately to severely active Crohn's disease: results from the multicentre, randomised, double-blind, placebo-controlled, withdrawal phase 3 FORTIFY maintenance trial.

BACKGROUND: There is a great unmet need for new therapeutics with novel mechanisms of action for patients with Crohn's disease. The ADVANCE and MOTIVATE studies showed that intravenous risankizumab, a selective p19 anti-interleukin (IL)-23 antibody, was efficacious and well tolerated as induction therapy. Here, we report the efficacy and safety of subcutaneous risankizumab as maintenance therapy. METHODS: FORTIFY is a phase 3, multicentre, randomised, double-blind, placebo-controlled, maintenance withdrawal study across 273 clinical centres in 44 countries across North and South America, Europe, Oceania, Africa, and the Asia-Pacific region that enrolled participants with clinical response to risankizumab in the ADVANCE or MOTIVATE induction studies. Patients in ADVANCE or MOTIVATE were aged 16-80 years with moderately to severely active Crohn's disease. Patients in the FORTIFY substudy 1 were randomly assigned again (1:1:1) to receive either subcutaneous risankizumab 180 mg, subcutaneous risankizumab 360 mg, or withdrawal from risankizumab to receive subcutaneous placebo (herein referred to as withdrawal [subcutaneous placebo]). Treatment was given every 8 weeks. Patients were stratified by induction dose, post-induction endoscopic response, and clinical remission status. Patients, investigators, and study personnel were masked to treatment assignments. Week 52 co-primary endpoints were clinical remission (Crohn's disease activity index [CDAI] in the US protocol, or stool frequency and abdominal pain score in the non-US protocol) and endoscopic response in patients who received at least one dose of study drug during the 52-week maintenance period. Safety was assessed in patients receiving at least one dose of study medication. This study is registered with ClinicalTrials.gov, NCT03105102. FINDINGS: 712 patients were initially assessed and, between April 9, 2018, and April 24, 2020, 542 patients were randomly assigned to either the risankizumab 180 mg group (n=179), the risankizumab 360 mg group (n=179), or the placebo group (n=184). Greater clinical remission and endoscopic response rates were reached with 360 mg risankizumab versus placebo (CDAI clinical remission was reached in 74 (52%) of 141 patients vs 67 (41%) of 164 patients, adjusted difference 15% [95% CI 5-24]; stool frequency and abdominal pain score clinical remission was reached in 73 (52%) of 141 vs 65 (40%) of 164, adjusted difference 15% [5-25]; endoscopic response 66 (47%) of 141 patients vs 36 (22%) of 164 patients, adjusted difference 28% [19-37]). Higher rates of CDAI clinical remission and endoscopic response (but not stool frequency and abdominal pain score clinical remission [p=0·124]) were also reached with risankizumab 180 mg versus withdrawal (subcutaneous placebo; CDAI clinical remission reached in 87 [55%] of 157 patients, adjusted difference 15% [95% CI 5-24]; endoscopic response 74 [47%] of 157, adjusted difference 26% [17-35]). Results for more stringent endoscopic and composite endpoints and inflammatory biomarkers were consistent with a dose-response relationship. Maintenance treatment was well tolerated. Adverse event rates were similar among groups, and the most frequently reported adverse events in all treatment groups were worsening Crohn's disease, arthralgia, and headache. INTERPRETATION: Subcutaneous risankizumab is a safe and efficacious treatment for maintenance of remission in patients with moderately to severely active Crohn's disease and offers a new therapeutic option for a broad range of patients by meeting endpoints that might change the future course of disease. FUNDING: AbbVie.

Risankizumab as induction therapy for Crohn's disease: results from the phase 3 ADVANCE and MOTIVATE induction trials.

BACKGROUND: Risankizumab, an interleukin (IL)-23 p19 inhibitor, was evaluated for safety and efficacy as induction therapy in patients with moderately to severely active Crohn's disease. METHODS: ADVANCE and MOTIVATE were randomised, double-masked, placebo-controlled, phase 3 induction studies. Eligible patients aged 16-80 years with moderately to severely active Crohn's disease, previously showing intolerance or inadequate response to one or more approved biologics or conventional therapy (ADVANCE) or to biologics (MOTIVATE), were randomly assigned to receive a single dose of intravenous risankizumab (600 mg or 1200 mg) or placebo (2:2:1 in ADVANCE, 1:1:1 in MOTIVATE) at weeks 0, 4, and 8. We used interactive response technology for random assignment, with stratification by number of previous failed biologics, corticosteroid use at baseline, and Simple Endoscopic Score for Crohn's disease (SES-CD). All patients and study personnel (excluding pharmacists who prepared intravenous solutions) were masked to treatment allocation throughout the study. Coprimary endpoints were clinical remission (defined by Crohn's disease activity index [CDAI] or patient-reported outcome criteria [average daily stool frequency and abdominal pain score]) and endoscopic response at week 12. The intention-to-treat population (all eligible patients who received at least one dose of study drug in the 12-week induction period) was analysed for efficacy outcomes. Safety was assessed in all patients who received at least one dose of study drug. Both trials were registered on ClinicalTrials.gov, NCT03105128 (ADVANCE) and NCT03104413 (MOTIVATE), and are now complete. FINDINGS: Participants were enrolled between May 10, 2017, and Aug 24, 2020 (ADVANCE trial), and Dec 18, 2017 and Sept 9, 2020 (MOTIVATE trial). In ADVANCE, 931 patients were assigned to either risankizumab 600 mg (n=373), risankizumab 1200 mg (n=372), or placebo (n=186). In MOTIVATE, 618 patients were assigned to risankizumab 600 mg (n=206), risankizumab 1200 mg (n=205), or placebo (n=207). The primary analysis population comprised 850 participants in ADVANCE and 569 participants in MOTIVATE. All coprimary endpoints at week 12 were met in both trials with both doses of risankizumab (p values ≤0·0001). In ADVANCE, CDAI clinical remission rate was 45% (adjusted difference 21%, 95% CI 12-29; 152/336) with risankizumab 600 mg and 42% (17%, 8-25; 141/339) with risankizumab 1200 mg versus 25% (43/175) with placebo; stool frequency and abdominal pain score clinical remission rate was 43% (22%, 14-30; 146/336) with risankizumab 600 mg and 41% (19%, 11-27; 139/339) with risankizumab 1200 mg versus 22% (38/175) with placebo; and endoscopic response rate was 40% (28%, 21-35; 135/336) with risankizumab 600 mg and 32% (20%, 14-27; 109/339) with risankizumab 1200 mg versus 12% (21/175) with placebo. In MOTIVATE, CDAI clinical remission rate was 42% (22%, 13-31; 80/191) with risankizumab 600 mg and 40% (21%, 12-29; 77/191) with risankizumab 1200 mg versus 20% (37/187) with placebo; stool frequency and abdominal pain score clinical remission rate was 35% (15%, 6-24; 66/191) with risankizumab 600 mg and 40% (20%, 12-29; 76/191) with risankizumab 1200 mg versus 19% (36/187) with placebo; and endoscopic response rate was 29% (18%, 10-25; 55/191) with risankizumab 600 mg and 34% (23%, 15-31; 65/191) with risankizumab 1200 mg versus 11% (21/187) with placebo. The overall incidence of treatment-emergent adverse events was similar among the treatment groups in both trials. Three deaths occurred during induction (two in the placebo group [ADVANCE] and one in the risankizumab 1200 mg group [MOTIVATE]). The death in the risankizumab-treated patient was deemed unrelated to the study drug. INTERPRETATION: Risankizumab was effective and well tolerated as induction therapy in patients with moderately to severely active Crohn's disease. FUNDING: AbbVie.

Long-Term Safety and Efficacy of Risankizumab Treatment in Patients with Crohn's Disease: Results from the Phase 2 Open-Label Extension Study.

BACKGROUND AND AIMS: Risankizumab, an interleukin-23 antibody, demonstrated efficacy and acceptable safety in a phase 2 study of patients with moderate-to-severe refractory Crohn's disease. This open-label extension investigated the long-term safety, pharmacokinetics, immunogenicity and efficacy of risankizumab in responders to risankizumab in the parent phase 2 study. METHODS: Enrolled patients had achieved clinical response [decrease in Crohn's Disease Activity Index from baseline ≥100] without clinical remission [Crohn's Disease Activity Index <150] at Week 26, or clinical response and/or remission at Week 52 in the parent phase 2 study and received open-label subcutaneous risankizumab 180 mg every 8 weeks. RESULTS: Sixty-five patients were enrolled, including four who had lost response in the parent study and were first reinduced with risankizumab 600 mg every 4 weeks [three infusions]. Patients received risankizumab for a median of 33 months [total: 167.0 patient-years]. The rate of serious adverse events was 24.6 events/100 patient-years; the majority were gastrointestinal in nature. Rates of serious infections, opportunistic infections and fungal infections were 4.2, 1.8, and 6.6 events/100 patient-years, respectively. No deaths, malignancies, adjudicated major adverse cardiovascular events, latent/active tuberculosis or herpes zoster were reported. Treatment-emergent anti-drug antibodies developed in eight patients [12.3%]; none were neutralizing. Efficacy outcomes were maintained during the study, including the proportions of patients [observed analysis] with clinical remission [>71%] and endoscopic remission [>42%]. CONCLUSIONS: Long-term maintenance treatment with subcutaneous risankizumab 180 mg every 8 weeks was well tolerated by patients with Crohn's disease, with no new safety signals. Clinical trial registration number: NCT02513459.

Correlation of Stool Frequency and Abdominal Pain Measures With Simple Endoscopic Score for Crohn's Disease.

BACKGROUND: The Crohn's Disease Activity Index (CDAI) has been criticized for being weakly correlated with bowel inflammation. We assessed correlation between Simple Endoscopic Score for Crohn's Disease (SES-CD) and individual CDAI items stratified by disease location to better understand this relationship. METHODS: We pooled patient-level data from 3 placebo-controlled Crohn's disease (CD) trials that tested adalimumab, upadacitinib, and risankizumab. Disease location was defined as ileum only, colon only, or ileocolonic based upon colonoscopy at study entry. Pearson correlation coefficients and linear regression assessed correlations between items of the CDAI and SES-CD. RESULTS: A total of 353 patients were included (20.7% ileal, 30.6% colonic, 48.7% ileocolonic disease). Crohn's Disease Activity Index and SES-CD scores were moderately correlated (R = 0.33; P < 0.001). Among CDAI items, the strongest correlations with SES-CD were seen with very soft or liquid stool frequency (SF) and patient-reported outcome 2 (PRO2; which includes SF and abdominal pain score; both R = 0.36; P < 0.001); these correlations were numerically stronger in colonic disease (SF: R = 0.46; P < 0.001; PRO2: R = 0.44; P < 0.001) than in ileal disease (SF: R = 0.14; P = 0.23; PRO2: R = 0.21; P = 0.07), although a test for interaction was not significant. In adjusted linear regression models, the proportion of mucosa that was inflamed and the proportion of mucosa with ulceration were positively correlated, whereas the presence of strictures was inversely correlated with SF. CONCLUSIONS: The SF item of the CDAI is moderately correlated with SES-CD and independently correlated with mucosal ulceration, inflammation, and strictures. Understanding why bowel inflammation as measured endoscopically does not correlate more strongly with patients' symptoms could help develop scales that link CD pathology to patient experience.

Efficacy and Safety of Dose Escalation to Adalimumab 80 mg Every Other Week in Japanese Patients with Crohn's Disease Who Lost Response to Maintenance Therapy.

BACKGROUND: Dose escalation is often recommended for loss of response in anti-TNFα-treated patients with Crohn's disease (CD). This 52-week phase 3, multicenter study investigated the efficacy and safety of escalation to adalimumab 80 mg every other week (EOW) in Japanese patients with CD who lost response to maintenance adalimumab 40 mg EOW. METHODS: Twenty-eight patients aged ≥15 years with moderately to severely active CD who had previously attained and subsequently lost clinical response to maintenance ada limumab received open-label adalimumab 80 mg EOW during weeks 0-50. Loss of response was defined as CD activity index (CDAI) ≥200, increases in CDAI ≥50 from minimum observed value, and C-reactive protein (CRP) ≥1 mg/dL at screening. The primary endpoint was the proportion of patients achieving a CDAI decrease ≥50 (CR-50) from baseline at week 8. RESULTS: At weeks 8 and 52, 75.0 and 57.1$ of patients achieved CR-50 and 25.0 and 35.7$ achieved clinical remission (CDAI < 150), respectively; median CRP changes from baseline were -0.39 and -0.77 mg/dL, respectively. Most treatment-emergent adverse events were mild to moderate. CONCLUSIONS: Adalimumab dose escalation to 80 mg EOW improved CD activity in patients who had lost response to maintenance adalimumab, with no new safety signals. (ClinicalTrials.gov Identifier: NCT01958827.).

Selective IL-23 Inhibition by Risankizumab Modulates the Molecular Profile in the Colon and Ileum of Patients With Active Crohn's Disease: Results From a Randomised Phase II Biopsy Sub-study.

BACKGROUND AND AIMS: We aimed to investigate the underlying mechanism of action of risankizumab, a monoclonal antibody targeting the IL-23 p19 subunit, previously reported to induce clinical and endoscopic remission in a randomised phase II study in patients with active Crohn's disease. METHODS: Ileum and colon biopsies obtained at screening and Week 12 from a subgroup of patients [n = 106] in the risankizumab phase II study were analysed by transcriptome-wide RNA-Seq profiling. Univariate associations were assessed using linear modelling. RESULTS: By Week 12, risankizumab significantly decreased [p < 0.005] the expression of 1880 and 765 genes in the colon [false-discovery rate = 0.02] and ileum [false-discovery rate = 0.05], respectively. These genes were associated with the IL-23/IL-17 axis, Th1 pathway, innate immunity, and tissue turnover. Colonic transcriptomic profiles following risankizumab treatment reflected the transcriptomic changes observed in patients achieving endoscopic response and remission at Week 12 and were significantly different from placebo [p < 0.005]. The colonic transcriptomic profile, significantly modulated by risankizumab at Week 12, was indicative of suppression of pathways associated with epithelial biology. Furthermore, pathways associated with Crohn's disease modulated by risankizumab treatment included second messenger-mediated signalling, immune response, lymphocyte and leucocyte activation, lymphocyte differentiation and cell-cell adhesion. CONCLUSIONS: Endoscopic remission and response observed with risankizumab in patients with active Crohn's disease was associated with significant transcriptomic changes in the colon, compared with placebo. Differentiated expression of genes associated with the IL-23/IL-17 axis was observed in the colon and ileum 12 weeks after risankizumab treatment.

Risankizumab in patients with moderate to severe Crohn's disease: an open-label extension study.

BACKGROUND: Risankizumab, an anti-interleukin 23 antibody, was superior to placebo in achieving clinical and endoscopic remission at week 12 in a randomised, phase 2 induction study in patients with moderately to severely active Crohn's disease. Here we aimed to assess the efficacy and safety of extended intravenous induction and subcutaneous maintenance therapy with risankizumab. METHODS: All patients who completed the 12-week induction phase of the double-blind phase 2 induction study were included in this open-label extension study. Patients who did not achieve deep remission, defined as clinical remission (Crohn's Disease Activity Index [CDAI] <150) and endoscopic remission (Crohn's Disease Endoscopic Index of Severity [CDEIS] ≤4, or ≤2 for patients with isolated ileitis), at week 12 received open-label intravenous therapy with 600 mg risankizumab every 4 weeks for 12 weeks; patients in deep remission at week 12 entered a 12-week washout phase. Patients in clinical remission at week 26 were invited to participate in the maintenance phase of the study, in which they received open-label subcutaneous risankizumab (180 mg) every 8 weeks for 26 weeks. 26-week efficacy endpoints were the proportion of patients in clinical remission (CDAI <150), and the proportion of patients who achieved clinical response (either CDAI of <150 or a reduction from baseline of at least 100 points). 52-week efficacy endpoints were the proportion of patients achieving: clinical remission; clinical response; endoscopic response (>50% CDEIS reduction from baseline); endoscopic remission, as defined previously; mucosal healing; and deep remission. Safety was assessed in patients who received at least one dose of the study drug during the open-label phases of the study. This study is registered with ClinicalTrials.gov, number NCT02031276. FINDINGS: Of the 108 patients who completed the 12-week double-blind induction trial, six patients were in deep remission and entered the 12-week washout phase. 102 patients were not in deep remission, 101 of whom received 12 weeks of 600 mg risankizumab (33 from the original placebo group, 34 from the 200 mg risankizumab group, and 34 from the 600 mg risankizumab group); the other patient declined to continue the study. At week 26, 54 (53%) of 101 patients treated with 600 mg rizankizumab were in clinical remission. Among patients included in the open-label extension trial, clinical remission rates at week 26 versus week 12 were: 18 (55%) versus six (18%) of 33 patients in the original placebo group; 20 (59%) versus seven (21%) of 34 patients in the original 200 mg risankizumab group; and 16 (47%) versus nine (26%) of 34 patients in the original 600 mg risankizumab group. 62 patients received risankizumab maintenance treatment, including the 54 patients who achieved clinical remission at week 26, the six patients who had achieved deep remission at week 12, and one patient because of a protocol violation. At week 52, clinical remission was maintained in 44 (71%) patients; 50 (81%) patients had a clinical response, 22 (35%) patients were in endoscopic remission, and 34 (55%) patients had an endoscopic response. 15 (24%) patients had mucosal healing and 18 (29%) patients achieved deep remission at week 52. Risankizumab was well tolerated with no new safety signals noted. The most frequent treatment-emergent adverse events were arthralgia (25 [22%] of 115 patients), headache (23 [20%]), abdominal pain (21 [18%]), nasopharyngitis (18 [16%]), nausea (18 [16%]), and pyrexia (15 [13%]). Most adverse events were mild or moderate and considered to be unrelated to study treatment. There were no treatment-related deaths. INTERPRETATION: Extended induction treatment with open-label intravenous risankizumab was effective in increasing clinical response and remission rates at week 26. Open-label subcutaneous risankizumab maintained remission until week 52 in most patients who were in clinical remission at week 26. Selective blockade of interleukin 23 warrants further investigation as a treatment for Crohn's disease. FUNDING: Boehringer Ingelheim.

Performance of Crohn's disease Clinical Trial Endpoints based upon Different Cutoffs for Patient Reported Outcomes or Endoscopic Activity: Analysis of EXTEND Data.

Background: Clinical trial endpoints for Crohn's disease (CD) activity correlate poorly with mucosal inflammation; to assess treatment efficacy, patient-reported outcomes and endoscopic assessments are preferred. This study assessed the impact on treatment efficacy estimations of using different definitions of clinical and endoscopic remission and endoscopic response, and of using site- or central-based endoscopy evaluation. Methods: This post hoc analysis of data fromEXTEND (extend the safety and efficacy of adalimumab through endoscopic healing), a placebo (PBO)-controlled, randomized trial of adalimumab (ADA) for mucosal healing, included adults with moderate-to-severe CD. Subsets of patients meeting specified Simplified Endoscopic Score for CD (SES-CD) inclusion criteria, according to site or central reading, and baseline stool frequency (SF) and/or abdominal pain score (AP) thresholds were evaluated. Various endpoint definitions based on the Crohn's Disease Activity Index (CDAI), its SF and AP components, SES-CD, and composite endpoints were compared between treatment groups. Results: Increased stringency of Week 12 clinical endpoints compared to CDAI<150 to SF≤3.0/1.5&AP≤1.0 reduced PBO response rates by ≥12% and increased treatment effects by ≤10%. Amending the SES-CD endpoint from ≤4 to ≤2 reduced the treatment effect from 24% to 8%. Composite endpoints further diminished response rates and effect sizes. Site-based evaluation was associated with lower remission rates versus central reading in the PBO group and, thus, greater ADA-related treatment effects. Conclusions: This analysis is the first to demonstrate that increasing the stringency of clinical and endoscopic endpoint definitions in CD trials, especially lowering SF or SES-CD definitions, reduces the ability to detect treatment-related change in CD activity; focus on endpoints that reflect clinical change is warranted.

Effect of tight control management on Crohn's disease (CALM): a multicentre, randomised, controlled phase 3 trial.

BACKGROUND: Biomarkers of intestinal inflammation, such as faecal calprotectin and C-reactive protein, have been recommended for monitoring patients with Crohn's disease, but whether their use in treatment decisions improves outcomes is unknown. We aimed to compare endoscopic and clinical outcomes in patients with moderate to severe Crohn's disease who were managed with a tight control algorithm, using clinical symptoms and biomarkers, versus patients managed with a clinical management algorithm. METHODS: CALM was an open-label, randomised, controlled phase 3 study, done in 22 countries at 74 hospitals and outpatient centres, which evaluated adult patients (aged 18-75 years) with active endoscopic Crohn's disease (Crohn's Disease Endoscopic Index of Severity [CDEIS] >6; sum of CDEIS subscores of >6 in one or more segments with ulcers), a Crohn's Disease Activity Index (CDAI) of 150-450 depending on dose of prednisone at baseline, and no previous use of immunomodulators or biologics. Patients were randomly assigned at a 1:1 ratio to tight control or clinical management groups, stratified by smoking status (yes or no), weight (<70 kg or ≥70 kg), and disease duration (≤2 years or >2 years) after 8 weeks of prednisone induction therapy, or earlier if they had active disease. In both groups, treatment was escalated in a stepwise manner, from no treatment, to adalimumab induction followed by adalimumab every other week, adalimumab every week, and lastly to both weekly adalimumab and daily azathioprine. This escalation was based on meeting treatment failure criteria, which differed between groups (tight control group before and after random assignment: faecal calprotectin ≥250 µg/g, C-reactive protein ≥5mg/L, CDAI ≥150, or prednisone use in the previous week; clinical management group before random assignment: CDAI decrease of <70 points compared with baseline or CDAI >200; clinical management group after random assignment: CDAI decrease of <100 points compared with baseline or CDAI ≥200, or prednisone use in the previous week). De-escalation was possible for patients receiving weekly adalimumab and azathioprine or weekly adalimumab alone if failure criteria were not met. The primary endpoint was mucosal healing (CDEIS <4) with absence of deep ulcers 48 weeks after randomisation. Primary and safety analyses were done in the intention-to-treat population. This trial has been completed, and is registered with ClinicalTrials.gov, number NCT01235689. FINDINGS: Between Feb 11, 2011, and Nov 3, 2016, 244 patients (mean disease duration: clinical management group, 0·9 years [SD 1·7]; tight control group, 1·0 year [2·3]) were randomly assigned to monitoring groups (n=122 per group). 29 (24%) patients in the clinical management group and 32 (26%) patients in the tight control group discontinued the study, mostly because of adverse events. A significantly higher proportion of patients in the tight control group achieved the primary endpoint at week 48 (56 [46%] of 122 patients) than in the clinical management group (37 [30%] of 122 patients), with a Cochran-Mantel-Haenszel test-adjusted risk difference of 16·1% (95% CI 3·9-28·3; p=0·010). 105 (86%) of 122 patients in the tight control group and 100 (82%) of 122 patients in the clinical management group reported treatment-emergent adverse events; no treatment-related deaths occurred. The most common adverse events were nausea (21 [17%] of 122 patients), nasopharyngitis (18 [15%]), and headache (18 [15%]) in the tight control group, and worsening Crohn's disease (35 [29%] of 122 patients), arthralgia (19 [16%]), and nasopharyngitis (18 [15%]) in the clinical management group. INTERPRETATION: CALM is the first study to show that timely escalation with an anti-tumour necrosis factor therapy on the basis of clinical symptoms combined with biomarkers in patients with early Crohn's disease results in better clinical and endoscopic outcomes than symptom-driven decisions alone. Future studies should assess the effects of such a strategy on long-term outcomes such as bowel damage, surgeries, hospital admissions, and disability. FUNDING: AbbVie.

Adalimumab induction and maintenance therapy achieve clinical remission and response in Chinese patients with Crohn's disease.

BACKGROUND/AIMS: This was a Phase 2 study (NCT02015793) to evaluate the pharmacokinetics, safety, and efficacy of adalimumab in Chinese patients with Crohn's disease (CD). METHODS: Thirty, adult Chinese patients with CD (CD Activity Index [CDAI] 220-450; high-sensitivity [hs]-C-reactive protein [CRP] ≥3 mg/L) received double-blind adalimumab 160/80 mg or 80/40 mg at weeks 0/2, followed by 40 mg at weeks 4 and 6. An open-label extension period occurred from weeks 8-26; patients received 40 mg adalimumab every other week. Serum adalimumab concentration and change from baseline in fecal calprotectin (FC) were measured during the double-blind period. Clinical remission (CDAI <150), response (decrease in CDAI ≥70 points from baseline), and change from baseline in hs-CRP were assessed through week 26. Nonresponder imputation was used for missing categorical data and last observation carried forward for missing hs-CRP/FC values. No formal hypothesis was tested. Adverse events were monitored. RESULTS: Mean adalimumab serum concentrations during the induction phase were 13.9-18.1 µg/mL (160/80 mg group) and 7.5-9.5 µg/mL (80/40 mg group). During the double-blind period, higher remission/response rates and greater reductions from baseline in hs-CRP and FC were observed with adalimumab 160/80 mg compared to that with 80/40 mg. Adverse event rates were similar among all treatment groups. CONCLUSIONS: Adalimumab serum concentrations in Chinese patients with CD were comparable to those observed previously in Western and Japanese patients. Clinically meaningful remission rates and improvement in inflammatory markers were achieved with both dosing regimens; changes occurred rapidly with adalimumab 160/80 mg induction therapy. No new safety signals were reported.

Immunopathology of inflammatory bowel disease.

Inflammatory bowel disease (IBD) results from a complex series of interactions between susceptibility genes, the environment, and the immune system. The host microbiome, as well as viruses and fungi, play important roles in the development of IBD either by causing inflammation directly or indirectly through an altered immune system. New technologies have allowed researchers to be able to quantify the various components of the microbiome, which will allow for future developments in the etiology of IBD. Various components of the mucosal immune system are implicated in the pathogenesis of IBD and include intestinal epithelial cells, innate lymphoid cells, cells of the innate (macrophages/monocytes, neutrophils, and dendritic cells) and adaptive (T-cells and B-cells) immune system, and their secreted mediators (cytokines and chemokines). Either a mucosal susceptibility or defect in sampling of gut luminal antigen, possibly through the process of autophagy, leads to activation of innate immune response that may be mediated by enhanced toll-like receptor activity. The antigen presenting cells then mediate the differentiation of naïve T-cells into effector T helper (Th) cells, including Th1, Th2, and Th17, which alter gut homeostasis and lead to IBD. In this review, the effects of these components in the immunopathogenesis of IBD will be discussed.

SUSTAINED TL1A (TNFSF15) EXPRESSION ON BOTH LYMPHOID AND MYELOID CELLS LEADS TO MILD SPONTANEOUS INTESTINAL INFLAMMATION AND FIBROSIS.

TL1A is a member of the TNF superfamily, and its expression is increased in the mucosa of inflammatory bowel disease patients. Moreover, patients with certain TNFSF15 variants over-express TL1A and have a higher risk of developing strictures in the small intestine. Consistently, mice with sustained Tl1a expression in either lymphoid or myeloid cells develop spontaneous ileitis and increased intestinal collagen deposition. Transgenic (Tg) mice with constitutive Tl1a expression in both lymphoid and myeloid cells were generated to assess their in vivo consequence. Constitutive expression of Tl1a in both lymphoid and myeloid cells showed increased spontaneous ileitis and collagen deposition than WT mice. T cells with constitutive expression of Tl1a in both lymphoid and myeloid cells were found to have a more activated phenotype, increased gut homing marker CCR9 expression, and enhanced Th1 and Th17 cytokine activity than WT mice. Although no differences in T cell activation marker, Th1 or Th17 cytokine activity, ileitis, or collagen deposition were found between constitutive Tl1a expression in lymphoid only, myeloid only, or combined lymphoid and myeloid cells. Double hemizygous Tl1a-Tg mice appeared to have worsened ileitis and intestinal fibrosis. Our findings confirm that TL1A-DR3 interaction is involved in T cell-dependent ileitis and fibrosis.

Leukocyte compartments in the mouse lung: distinguishing between marginated, interstitial, and alveolar cells in response to injury.

We developed a flow cytometry-based assay to simultaneously quantify multiple leukocyte populations in the marginated vascular, interstitial, and alveolar compartments of the mouse lung. An intravenous injection of a fluorescently labeled anti-CD45 antibody was used to label circulating and marginated vascular leukocytes. Following vascular flushing to remove non-adherent cells and collection of broncho-alveolar lavage (BAL) fluid, lungs were digested and a second fluorescent anti-CD45 antibody was added ex vivo to identify cells not located in the vascular space. In the naïve mouse lung, we found about 11 million CD45+ leukocytes, of which 87% (9.5 million) were in the vascular marginated compartment, consisting of 17% NK cells, 17% neutrophils, 57% mononuclear myeloid cells (monocytes, macrophage precursors and dendritic cells), and 10% T cells (CD4+, CD8+, and invariant NKT cells). Non-vascular compartments including the interstitial compartment contained 7.7×10(5)cells, consisting of 49% NK cells, 25% dendritic cells, and 16% other mononuclear myeloid cells. The alveolar compartment was overwhelmingly populated by macrophages (5.63×10(5)cells, or 93%). We next studied leukocyte margination and extravasation into the lung following acid injury, a model of gastric aspiration. At 1 h after injury, neutrophils were markedly elevated in the blood while all other circulating leukocytes declined by an average of 79%. At 4 h after injury, there was a peak in the numbers of marginated neutrophils, NK cells, CD4+ and CD8+ T cells and a peak in the number of alveolar NK cells. Most interstitial cells consisted of DCs, neutrophils, and CD4+ T cells, and most alveolar compartment cells consisted of macrophages, neutrophils, and NK cells. At 24 h after injury, there was a decline in the number of all marginated and interstitial leukocytes and a peak in alveolar neutrophils. In sum, we have developed a novel assay to study leukocyte margination and trafficking following pulmonary inflammation and show that marginated cells comprise a large fraction of lung leukocytes that increases shortly after lung injury. This assay may be of interest in future studies to determine if leukocytes become activated upon adherence to the endothelium, and have properties that distinguish them from interstitial and circulating cells.