ASTRO Phase 3 Study: Efficacy and Safety of SC Guselkumab

April 2026

Thank you to J&J for the support of this Journal Club Review Module.

In this journal club video, Sharon Dudley Brown, CRNP, PhD, from the IBD Center at Johns Hopkins University, reviews the ASTRO trial published in The Lancet, which evaluated subcutaneous guselkumab for the treatment of moderate to severe ulcerative colitis. The discussion highlights how this IL-23 inhibitor was studied in patients with difficult-to-treat disease who had previously failed or were intolerant to standard therapies. The trial compared different dosing strategies of subcutaneous guselkumab versus placebo and assessed clinical remission, symptom improvement, and endoscopic outcomes over time.

Results showed that patients receiving guselkumab had higher rates of remission and improved colon inflammation compared with placebo, with benefits seen early in treatment and sustained through follow-up. Safety outcomes were generally similar between groups, with no new safety concerns identified. Overall, the ASTRO trial supports subcutaneous guselkumab as an effective and well-tolerated option for patients with moderate to severe ulcerative colitis.