A Review of Selected Presentations From Digestive Disease Week 2026
May 2-5, 2026 • Chicago, Illinois
Efficacy and Safety of Guselkumab for Ulcerative Colitis Through Week 140 of the QUASAR Long-Term Extension Study
The interleukin (IL)-23 p19 subunit antagonist guselkumab received US Food and Drug Administration (FDA) approval for use in adult patients with moderately to severely active ulcerative colitis (UC) in 2024, following results from the phase 2b QUASAR trial in which guselkumab demonstrated clinical and endoscopic remissions in patients with moderately to severely active UC with an inadequate response and/or intolerance to corticosteroids, immunosuppressants, or advanced therapy.1
The double-blind, randomized, placebo-controlled phase 3 QUASAR program included an induction trial in which patients were randomly assigned 3:2 to intravenous guselkumab 200 mg or placebo administered at weeks 0, 4, and 8, followed by a maintenance trial, which was open to patients with a clinical response to guselkumab after week 12, or who crossed over from placebo to guselkumab and attained a response at week 24.2 In the maintenance trial, patients were randomly assigned to subcutaneous guselkumab administered at 200 mg every 4 weeks (Q4W) or 100 mg every 8 weeks (Q8W), or placebo (guselkumab withdrawal) for 44 weeks.
Patients who completed the maintenance week 44 visit and for whom the investigator thought continued study treatment could be beneficial could enroll in the long-term extension (LTE) study. In the LTE, patients in the subcutaneous guselkumab arms continued to receive their assigned maintenance dosing (200 mg Q4W or 100 mg Q8W) and patients in the placebo arm discontinued after study unblinding.
At Digestive Disease Week (DDW) 2026, Peyrin-Biroulet and colleagues reported the efficacy and safety results of guselkumab in the LTE.3 Overall, 87% of patients initially assigned to guselkumab in the maintenance study (N=303) continued on the LTE and 89% of patients who started the LTE received 140 weeks of treatment. Efficacy outcomes in the LTE were assessed for patients with a baseline modified Mayo score of 5 to 9 who received guselkumab through the LTE and had no dose adjustments.
In the as-observed analysis at maintenance week 140, the rate of clinical remissions, defined as a Mayo stool frequency subscore (SFS) of 0 or 1 and not increased from induction baseline, a rectal bleeding subscore (RBS) of 0, and a Mayo endoscopic score (MES) of 0 or 1, was 81% with guselkumab 200 mg Q4W and 80% with guselkumab 100 mg Q8W. Of the patients in clinical remission at week 140, 98% were corticosteroid-free for at least 8 weeks before maintenance week 140. Rates of symptomatic remission, defined as an SFS of 0 or 1 and not increased from induction baseline and an RBS of 0, were 92% with both doses (Figure 1).
Investigators also reported endoscopic outcomes in patients receiving guselkumab in the LTE. Rates of endoscopic improvement (MES 0-1) at maintenance week 140 were 85% with guselkumab 200 mg Q4W and 84% with guselkumab 100 mg Q8W. Rates of endoscopic remission (normalization) were 56% and 51%, respectively, and rates of histo-endoscopic mucosal improvement were 80% and 77%, respectively.
Efficacy rates in the LTE were numerically lower in the nonresponder imputation analysis compared with the as-observed results, but trends were generally consistent, which investigators attributed to a high retention rate during the LTE.3 In subgroup analyses, efficacy outcomes at maintenance week 140 were consistent regardless of patients’ prior exposure to biologic and Janus kinase (JAK) inhibitors, and whether they had a prior inadequate response or intolerability to biologics and JAK inhibitors.
Safety outcomes were assessed for patients with a baseline modified Mayo score of 5 to 9 who completed the maintenance study and received any treatment in the LTE. The analysis revealed no new safety issues. There was 1 death in a guselkumab-treated patient caused by aortic dissection that was considered unrelated to the treatment. Rates of serious infections were below 2% across arms. No cases of active tuberculosis or opportunistic infection were reported. There were also no reports of anaphylaxis, serum sickness, or Hy’s law cases. Based on these findings, investigators concluded that guselkumab was associated with a favorable long-term benefit-risk profile.
Investigators also evaluated the association between efficacy outcomes following guselkumab induction and maintenance and likelihood of attaining corticosteroid-free remission at week 92 in the LTE.4 Overall, patients who attained endoscopic, histologic, or composite outcomes after guselkumab induction and 1 year of maintenance therapy were more likely to attain corticosteroid-free remission at LTE week 92. Across outcomes assessed, the proportion of patients achieving corticosteroid-free clinical remission at LTE week 92 was 72% to 81% for patients who attained that outcome at maintenance week 44 compared with 44% to 59% for those who did not. Composite outcomes were not superior to individual outcomes for predicting corticosteroid-free clinical remission. Investigators concluded that the findings support use of shorter-term endoscopic and histologic outcomes in patients with moderately to severely active UC.
References
1. Peyrin-Biroulet L, Allegretti JR, Rubin DT, et al; QUASAR Study Group. Guselkumab in patients with moderately to severely active ulcerative colitis: QUASAR phase 2b induction study. Gastroenterology. 2023;165(6):1443-1457.
2. Rubin DT, Allegretti JR, Panés J, et al; QUASAR Study Group. Guselkumab in patients with moderately to severely active ulcerative colitis (QUASAR): phase 3 double-blind, randomised, placebo-controlled induction and maintenance studies. Lancet. 2025;405(10472):33-49.
3. Peyrin-Biroulet L, Bressler B, Dignass A, et al. Efficacy and safety of guselkumab for ulcerative colitis through week 140 of the QUASAR long-term extension study [DDW abstract Su1645]. Gastroenterology. 2026;170(6):S1114-S1115.
4. Magro F, Rubin DT, Lichtenstein GR, et al. Association of endoscopic, histologic, and composite outcomes with long-term guselkumab efficacy in ulcerative colitis: 2-year results from the QUASAR LTE [DDW abstract Su1666]. Gastroenterology. 2026;170(6):S-893.
Impact of Obefazimod Treatment on Histologic and Combined Histologic-Endoscopic Outcomes in Patients With Moderately to Severely Active Ulcerative Colitis: Results From the ABTECT-1 and ABTECT-2 Phase 3, Double-Blind, Placebo-Controlled Induction Trials
Obefazimod is an investigational orally administered small molecule that selectively upregulates expression of microRNA-124 (miR-124), a regulator of inflammatory responses.1 Through its effects on miR-124, obefazimod reduces levels of proinflammatory cytokines, including IL-17, IL-6, and the chemokine CCL2.
In a phase 2 trial in patients with UC, obefazimod demonstrated clinical benefit and favorable safety as induction therapy and in an open-label maintenance period.2,3 At 96 weeks in 164 patients, obefazimod was associated with a clinical response rate of 72.8%, a clinical remission rate of 52.5%, an endoscopic improvement rate of 59.0%, and an endoscopic remission rate of 35.9%.3 The most frequent treatment-emergent adverse events (TEAEs) were COVID-19 (14.3%) and headache (11.5%).
Based on this demonstrated activity and safety in the phase 2 trial, the randomized phase 3 ABTECT-1 and ABTECT-2 trials were undertaken to further evaluate obefazimod in patients with UC. The trials enrolled a total of 1275 patients with moderately to severely active UC with prior failure of conventional and/or biologic therapy, JAK inhibitors, or sphingosine-1-phosphase (S1P) receptor modulators. Patients were randomly assigned 2:1:1 to obefazimod 50 mg, obefazimod 25 mg, or placebo, each administered daily for 8 weeks. Patients attaining a response at 8 weeks could proceed to the maintenance trial, in which they were randomly assigned 1:1:1 to obefazimod 50 mg, obefazimod 25 mg, or placebo for 52 weeks.
At DDW 2026, Magro and colleagues reported efficacy outcomes after 8 weeks of induction treatment in the ABTECT-1 (N=639) and ABTECT-2 (N=636) trials.4 Baseline characteristics were generally well balanced across trials and study arms; however, investigators noted that the patient population in the obefazimod 25-mg arm of ABTECT-2 had slightly more severe and refractory disease than in the obefazimod 25-mg arm of ABTECT-1. This is illustrated in the higher rates of patients with extensive colitis (42.8% vs 39.4%), a higher median fecal calprotectin level (2041 vs 1499 μg/g), and a higher proportion of patients with an inadequate response to advanced therapies (25.0% vs 21.4%).
In a pooled analysis of the ABTECT-1 and ABTECT-2 trials, at week 8, clinical and symptomatic endpoints were all significantly improved with obefazimod compared with placebo at both doses tested (P<.0001 for each comparison). These included the primary endpoint of clinical remission rate (17.6% with obefazimod 25 mg, 20.8% with obefazimod 50 mg, and 4.4% with placebo) (Figure 2), as well as the secondary endpoints of clinical response rate (59.6%, 62.1%, and 30.9%, respectively) and symptomatic remission rate (37.9%, 40.7%, and 19.9%, respectively).
Obefazimod was also associated with significant improvements over placebo in endoscopic and histologic endpoints in the pooled analysis. Rates of endoscopic improvement were 29.8% with obefazimod 25 mg, 34.4% with obefazimod 50 mg, and 7.9% with placebo (P<.0001 for each), and rates of endoscopic remission were 16.3%, 18.4%, and 5.0%, respectively (P<.0001 for each).
Rates of histologic improvement (Geboes histologic score ≤3.1) and histologic remission (Geboes histologic score <2A.0) at week 8 were also significantly higher with obefazimod compared with placebo in the pooled analysis. Histologic improvement rates were 38.6% with obefazimod 25 mg, 41.7% with obefazimod 50 mg, and 18.9% with placebo; rates of histologic remission were 10.7%, 9.3%, and 5.0%, respectively. Week 8 combined histologic-endoscopic outcomes were also significantly improved with obefazimod.
In subgroup analyses according to prior treatment, obefazimod 50 mg was associated with improved endoscopic and histologic outcomes regardless of whether patients had a prior inadequate response to advanced therapies, although the effect of obefazimod was stronger in patients without a prior inadequate response. Investigators concluded that the trials demonstrated clinically meaningful improvements in endoscopic, histologic, and combined outcomes at week 8.
References
1. Apolit C, Campos N, Vautrin A, et al. ABX464 (obefazimod) upregulates miR-124 to reduce proinflammatory markers in inflammatory bowel diseases. Clin Transl Gastroenterol. 2023;14(4):e00560.
2. Vermeire S, Sands BE, Tilg H, et al. ABX464 (obefazimod) for moderate-to-severe, active ulcerative colitis: a phase 2b, double-blind, randomised, placebo-controlled induction trial and 48 week, open-label extension. Lancet Gastroenterol Hepatol. 2022;7(11):1024-1035.
3. Vermeire S, Solitano V, Peyrin-Biroulet L, et al. Obefazimod: a first-in-class drug for the treatment of ulcerative colitis. J Crohns Colitis. 2023;17(10):1689-1697.
4. Magro F, Sands BE, Danese S, et al. Impact of obefazimod treatment on histologic and combined histologic-endoscopic outcomes in patients with moderately to severely active ulcerative colitis: results from the ABTECT-1 and ABTECT-2 phase 3, double-blind, placebo-controlled induction trials [DDW abstract 724]. Gastroenterology. 2026;170(6):S-893.
Symptomatic Improvement With Intravenous Guselkumab Induction Therapy Is Observed Early in Patients With Moderately to Severely Active Ulcerative Colitis: Post-Hoc Analysis of QUASAR
In patients with UC, symptoms such as rectal bleeding and stool frequency are significantly associated with reduced health-related quality of life.1 Accordingly, symptomatic relief has been identified as a short-term treatment target for patients with UC in the STRIDE-II treat-to-target framework.2
At DDW 2026, Dignass and colleagues presented results from a post-hoc analysis from the QUASAR induction trial evaluating symptomatic improvement during the first 14 days of therapy in patients with moderately to severely active UC.3 Symptomatic efficacy in the first 14 days of treatment was assessed based on changes in stool frequency and rectal bleeding.
The benefit of guselkumab over placebo in improving UC symptoms was evident as early by day 6. At that time, significant improvements were reported with guselkumab compared with placebo in the least squares mean change in Mayo SFS (-0.29 vs -0.17; P<.05) and RBS (-0.42 vs -0.30; P<.05).
These improvements with guselkumab over placebo translated to a significant increase by day 6 in the proportion of patients attaining symptomatic response, defined as a decrease in the sum of the stool frequency and RBS (by ≥30% and ≥1 point), at 29% vs 22% (P<.05). At day 14, the proportion of patients attaining symptomatic response with guselkumab and placebo increased to 42% and 26%, respectively (P<.001) (Figure 3).
The proportion of patients attaining an SFS of 1 or less was 23% with guselkumab and 18% with placebo at day 6, increasing to 30% and 22%, respectively, at day 14 (P<.05). The proportion of patients attaining rectal bleeding normalization (subscore of 0) was 18% and 14%, respectively, at day 6 and 29% and 21%, respectively, at day 14.
Investigators also reported an association between early symptomatic improvements and longer-term clinical outcomes in patients receiving guselkumab. Attaining symptomatic remission or response at day 14 was highly predictive of attaining clinical response at week 12, with positive predictive values (PPVs) of 86% and 74%, respectively.
The PPV for attaining a week 12 clinical remission based on early symptomatic improvements was lower, at 46% with a day 14 symptomatic remission and 31% with a day 14 symptomatic response. The PPV for predicting a week 44 clinical response was 77% for patients with symptomatic remission on day 14 and 69% for patients with a symptomatic response on day 14. The PPV for predicting a week 44 endoscopic response was 52% for patients with symptomatic remission on day 14 and 44% for patients with symptomatic response on day 14.
In an exploratory analysis, attaining stool frequency normalization at day 3 was associated with a higher likelihood of attaining favorable longer-term outcomes, including week 12 clinical remission (odds ratio [OR], 2.3; 95% CI, 1.1-4.8) and week 44 clinical remission (OR, 2.1; 95% CI, 1.0-4.4), clinical response (OR, 2.9; 95% CI, 1.3-6.4), and endoscopic remission (OR, 3.4; 95% CI, 1.6-7.6).
A comparison of the phase 3 ASTRO trial and the QUASAR trial found that early symptomatic outcomes are similar with subcutaneous guselkumab 400 mg as with intravenous guselkumab 200 mg, including week 2 symptomatic response rate (36% vs 34%) and week 2 symptomatic remission rate (12% for each).4
Investigators concluded that in patients with moderately to severely active UC, guselkumab is associated with both early symptomatic improvement that continues with ongoing treatment and long-term outcomes.
References
1. Aniwan S, Bruining DH, Park SH, et al. The combination of patient-reported clinical symptoms and an endoscopic score correlates well with health-related quality of life in patients with ulcerative colitis. J Clin Med. 2019;8(8):1171.
2. Turner D, Ricciuto A, Lewis A, et al; International Organization for the Study of IBD. STRIDE-II: an update on the Selecting Therapeutic Targets in Inflammatory Bowel Disease (STRIDE) initiative of the International Organization for the Study of IBD (IOIBD): determining therapeutic goals for treat-to-target strategies in IBD. Gastroenterology. 2021;160(5):1570-1583.
3. Dignass A, Hirai F, Saruta M, et al. Symptomatic improvement with intravenous guselkumab induction therapy is observed early in patients with moderately to severely active ulcerative colitis: post-hoc analysis of QUASAR [DDW abstract Mo1518]. Gastroenterology. 2026;170(6):S-1168.
4. Long M, Allegretti JR, Danese S, et al; ASTRO Study Group. Efficacy and safety of subcutaneous guselkumab induction therapy in participants with moderately to severely active ulcerative colitis (ASTRO): a double-blind, treat-through, randomised, placebo-controlled, phase 3 trial. Lancet Gastroenterol Hepatol. 2026;11(4):284-298.
Efficacy and Safety of the First Co-Antibody Therapy, JNJ-78934804, in Patients With Moderately to Severely Active Ulcerative Colitis Refractory to Systemic Therapies
A novel therapeutic approach being evaluated for inflammatory bowel disease involves use of co-antibody therapy that includes a fixed-dose combination of guselkumab and the anti–tumor necrosis factor antibody golimumab. In a proof-of-concept trial, the combination appeared to have enhanced efficacy, supporting its evaluating in a larger trial.1
In the phase 2b DUET-UC trial, Abreu and colleagues evaluated the fixed-dose guselkumab and golimumab combination JNJ-78934804 (also known as JNJ-4804) in 3 different doses and compared with single-agent therapy and placebo in patients with moderately to severely active UC with an inadequate response or intolerance to at least 1 systemic therapy mechanism.2 Among the 572 patients enrolled, 44.6% were refractory to 2 or more systemic therapy mechanisms.
The primary endpoint, clinical remission rate at week 48, was 41.0% with high-dose JNJ-4804, 26.7% with intermediate-dose JNJ-4804, and 22.3% with low-dose JNJ-4804, compared with 34.0% with single-agent guselkumab, 11.5% with single-agent golimumab, and 3.8% with placebo (Figure 4). Clinical remission rates were significantly higher with high-dose JNJ-4804 compared with golimumab and numerically higher than with guselkumab.
In patients refractory to 2 or more systemic therapy mechanisms, JNJ-4804 was more effective than either single antibody, and exceeded the additive effects of each antibody, among the clinical, endoscopic, and histologic-endoscopic endpoints assessed at week 48. Clinical remissions were attained at week 48 in 26.7% of patients refractory to 2 or more systemic therapy mechanisms (12 of 45 patients), and 91.7% of those patients (11 of 12) attained a corticosteroid-free clinical remission at week 48.
In the safety analysis, the most common TEAEs were UC and nasophyngitis. The overall rate of infections ranged across arms from 82.3 to 109.8 per 100 patient-years and was highest in the placebo arm. Most infections did not result in treatment discontinuation. Two opportunistic infections were reported, including 1 case of active tuberculosis in the intermediate-dose JNJ-4804 group and 1 case of esophageal candidiasis in the guselkumab arm. Malignancies included 3 new cases of basal cell carcinomas in patients with no prior history; all patients underwent excision and continued on the trial.
References
1. Feagan BG, Sands BE, Sandborn WJ, et al; VEGA Study Group. Guselkumab plus golimumab combination therapy versus guselkumab or golimumab monotherapy in patients with ulcerative colitis (VEGA): a randomised, double-blind, controlled, phase 2, proof-of-concept trial. Lancet Gastroenterol Hepatol. 2023;8(4):307-320.
2. Abreu MT, Sands BE, Vermeire S, et al. Efficacy and safety of the first co-antibody therapy, JNJ-78934804, in patients with moderately to severely active ulcerative colitis refractory to systemic therapies [DDW abstract 1058d]. Gastroenterology. 2026;170(6):S-2857-S-2858.
Efficacy of Etrasimod in Biologic/Janus Kinase Inhibitor-Naïve Patients With Mildly to Moderately Active Ulcerative Colitis: Results From the GLADIATOR Trial
Currently, no advanced therapies are FDA approved for patients with mildly to moderately active UC, which is defined as a modified Mayo score of 4 or more (including an endoscopic subscore [ES] ≥2 and an RBS ≥1).1 The selective S1P receptor modulator etrasimod is FDA approved for use in patients with moderately to severely active UC.
At DDW 2026, Yarur and colleagues presented results from the phase 2 GLADIATOR trial evaluating etrasimod in patients with mildly to moderately active UC.2 The trial enrolled 187 patients aged 18 to 80 years with a modified Mayo score of 4 to 6 (including an ES ≥2 and an RBS ≥1). Patients were randomly assigned 2:1 to etrasimod 2 mg or placebo, once daily for a 12-week induction period followed by a 40-week maintenance period.
At week 12, clinical remission rates were 28.3% with etrasimod and 11.7% with placebo (P=.007). At week 52, however, clinical remission rates were not significantly higher with etrasimod vs placebo, at 26.0% and 18.3%, respectively (P=.252). Thus, the trial did not meet its primary endpoint of week 52 clinical remission.
Investigators also evaluated the efficacy of etrasimod in a prespecified analysis of 150 patients without prior biologic or JAK inhibitor exposure who received etrasimod (n=104) or placebo (n=46). In this cohort, the mean age of enrolled patients was 40 years, and the mean UC disease duration was approximately 6 years. Females comprised 34.6% of patients in the etrasimod arm and 54.3% in the placebo arm. Prior and concomitant therapies consisted of only 5-aminosalicylates failure in 25.0% of patients in the etrasimod arm and 30.4% in the placebo arm. Baseline corticosteroid use was reported in 26.9% and 23.9% of patients, respectively.
In the subset of biologic/JAK inhibitor-naïve patients, week 12 clinical remission rates were 30.8% with etrasimod and 10.9% with placebo (P=.003) and week 52 clinical remission rates were 29.8% and 17.4%, respectively (P=.088) (Figure 5). In contrast, in the 37 patients who were biologic/JAK inhibitor-experienced, clinical remission rates at week 52 were 8.7% with etrasimod and 21.4% with placebo.
In the subset of biologic/JAK inhibitor-naïve patients, endoscopic and histologic outcomes were significantly higher with etrasimod vs placebo at week 12 and numerically higher at week 52. Specifically, at week 52, the proportion of patients with endoscopic improvement (defined as an ES ≤1 excluding friability) was 36.5% with etrasimod and 23.9% with placebo (P=.120) and the proportion of patients attaining endoscopic improvement and histologic remission (defined as an ES ≤1 with a Geboes Index score <2.0) was 27.9% and 19.6%, respectively (P=.279). The proportion of patients attaining sustained clinical remission, defined as a clinical remission at weeks 12 and 52, was 19.2% with etrasimod and 4.3% with placebo (P=.003).
Investigators noted that safety outcomes were reported previously and were consistent with the established safety profile of etrasimod.3 In reviewing the GLADIATOR findings, they cautioned that outcomes could have been affected by the small sample size and the high rate of discontinuation. Between weeks 12 and 52, 36.2% of patients in the etrasimod arm and 46.7% of those in the placebo arm discontinued treatment.
References
1. US Food and Drug Administration. Ulcerative colitis: developing drugs for treatment. Guidance for industry. April 2022. https://www.fda.gov/media/158016/download. Accessed May 21, 2026.
2. Yarur AJ, Dubinsky MC, Rubin DT, et al. efficacy of etrasimod in biologic/Janus kinase inhibitor-naïve patients with mildly to moderately active ulcerative colitis: results from the GLADIATOR trial [DDW abstract 728]. Gastroenterology. 2026;170(6):S-895.
3. Danese S, Goetsch M, Peyrin-Biroulet L, et al. The efficacy and safety of etrasimod in mildly to moderately active ulcerative colitis: results from the GLADIATOR trial. Gastroenterology. 2025;169(1):S188-S189.
Efficacy of Subcutaneous Guselkumab in Moderately to Severely Active Ulcerative Colitis by Induction Week 12 Clinical Response Status: Week 48 Results From the Phase 3 ASTRO Study
The randomized double-blind ASTRO trial demonstrated the efficacy of subcutaneous guselkumab as induction and maintenance treatment in patients with moderately to severely active UC.1 The phase 3 trial included a treat-through design, in which patients in the guselkumab arms were assigned to a specific induction and maintenance regimen and continued that regimen through the 48-week extension phase regardless of their clinical response status after the 12-week induction period.
At DDW 2026, Danese and colleagues presented results of an exploratory analysis of the ASTRO trial evaluating week 48 clinical and endoscopic outcomes based on clinical responses at week 12.2 The analysis included 267 patients who all received guselkumab 400 mg Q4W for 12 weeks as induction and were randomly assigned to maintenance guselkumab at 100 mg Q8W or 200 mg Q4W.
After 12 weeks of guselkumab induction, the clinical response rate was 67.4%. Clinical outcomes at week 48 were more favorable in patients attaining a clinical response after induction than in patients not attaining a clinical response after induction. Week 48 clinical response rates were 74.7% with guselkumab 100 mg Q8W and 82% with guselkumab 200 mg Q4W. However, a proportion of patients who did not attain a clinical response after induction therapy did attain clinical and endoscopic endpoints at week 48. Among patients without a response to induction therapy, the week 48 clinical response rate was 56.8% with guselkumab 100 mg Q8W and 48.8% with guselkumab 200 mg Q4W (Figure 6).
Week 48 clinical remission rates followed a similar pattern and were 51.6% with guselkumab 100 mg Q8W and 60.7% with guselkumab 200 mg Q4W among induction responders, and 25.0% and 25.6%, respectively for the two dose levels, among induction nonresponders.
Endoscopic outcomes at week 48 were also better in those attaining clinical response to induction therapy than in those without a response. Rates of endoscopic improvement among patients with a week 12 clinical response were 59.3% with guselkumab 100 mg Q8W and 66.3% with guselkumab 200 mg Q4W, and rates of endoscopic remission were 40.9% and 32.6%, respectively. In contrast, in patients without a response to induction therapy, rates of endoscopic improvement at week 48 at the 2 dose levels were 40.9% and 32.6%, and rates of endoscopic remission were 25.0% and 7.0%, respectively.
An analysis of baseline factors found that modified Mayo scores and Mayo endoscopy scores were higher among week 12 nonresponders, and these patients also appeared to be more refractory to newer agents than responders. Among patients without a response to induction therapy, there was no single factor that differentiated patients who went on to attain clinical remission from those who did not.
Investigators concluded that patients with a clinical response after guselkumab induction had better clinical and endoscopic outcomes at week 48. However, the observation of clinical and endoscopic endpoints at week 48 in a proportion of patients who did not attain a clinical response to induction suggests that continuing guselkumab after 12 weeks of induction therapy could be beneficial, regardless of whether a clinical response to induction therapy is achieved.
References
1. Long M, Allegretti JR, Danese S, et al; ASTRO Study Group. Efficacy and safety of subcutaneous guselkumab induction therapy in participants with moderately to severely active ulcerative colitis (ASTRO): a double-blind, treat-through, randomised, placebo-controlled, phase 3 trial. Lancet Gastroenterol Hepatol. 2026;11(4):284-298.
2. Danese S, Long M, Peyrin-Biroulet L, et al. Efficacy of subcutaneous guselkumab in moderately to severely active ulcerative colitis by induction week 12 clinical response status: week 48 results from the phase 3 ASTRO study [DDW abstract Mo1519]. Gastroenterology. 2026;170(6):S-1168.