What Is the Efficacy of Guselkumab in Ulcerative Colitis and Crohn's Disease?

In this comprehensive medication review, Peter Byrne, FNP, from South Denver Gastroenterology, discusses the efficacy of guselkumab in treating ulcerative colitis (UC) and Crohn’s disease (CD) based on key clinical trials, including Quasar and Galaxy 1.

Guselkumab has demonstrated significant efficacy in treating both ulcerative colitis (UC) and Crohn’s disease (CD), as highlighted in key clinical trials, including Quasar and Galaxy 1. In the Quasar trial, a Phase 3, randomized, placebo-controlled study, 701 patients with moderate to severe ulcerative colitis who had an inadequate response or intolerance to conventional or advanced therapies were evaluated. Patients received IV guselkumab (200 mg) or placebo at Weeks 0, 4, and 8, with the primary endpoint being clinical remission at Week 12. Results showed that 22.6% of guselkumab-treated patients achieved clinical remission compared to 7.9% with placebo, while 61.5% of patients on guselkumab showed a clinical response versus 27.9% on placebo. Additionally, 23.5% achieved histologic-endoscopic mucosal improvement (HEMI) versus 7.5% with placebo. In the maintenance phase, clinical remission at Week 44 was 50% with higher-dose guselkumab, 45.2% with the lower dose, and 18.9% with placebo, confirming its sustained efficacy.

For Crohn’s disease, the Galaxy 1 Phase 2 trial assessed guselkumab in patients with moderate to severe Crohn’s disease through an IV induction phase followed by subcutaneous maintenance therapy. At Week 12, 53% of guselkumab-treated patients achieved clinical remission compared to 16.4% on placebo, while clinical response rates were 65.9% versus 24.6% on placebo. Endoscopic response, defined as at least a 50% reduction in SC-CD score, was observed in 35.7% of guselkumab patients compared to 11.5% with placebo. Notably, bio-naïve patients had even higher response rates, with 47.5% achieving clinical remission versus 10% on placebo. In the maintenance phase, patients were assigned different dosing regimens, with 64%-73% achieving clinical remission depending on the dosage, compared to 57% in the ustekinumab group. Additionally, 44%-46% of guselkumab-treated patients showed an endoscopic response, while 18%-33% achieved endoscopic remission, compared to 30% and 6% in the ustekinumab group, respectively.

Overall, guselkumab has shown strong efficacy and a favorable safety profile in both ulcerative colitis and Crohn’s disease, with superior clinical, endoscopic, and histologic response rates compared to placebo. The Quasar and Galaxy 1 trials support its potential as a promising treatment option for inflammatory bowel disease (IBD). For further insights, visit the GHAPP website or download the GHAPP ACE app for more educational content.