Guselkumab for the Treatment of Crohn's Disease: Induction Results From the Phase 2 GALAXI-1 Study.

BACKGROUND & AIMS: Guselkumab, a selective p19 interleukin-23 antagonist, is approved for the treatment of plaque psoriasis and psoriatic arthritis. This study evaluated the efficacy and safety of guselkumab in patients with moderately to severely active Crohn's disease with inadequate response or intolerance to conventional or biologic therapy.

METHODS

GALAXI-1, a phase 2, double-blind, placebo-controlled study, randomized patients 1:1:1:1:1 to intravenous guselkumab 200 mg, 600 mg, or 1200 mg at weeks 0, 4, and 8; intravenous ustekinumab approximately 6 mg/kg at week 0 and 90 mg subcutaneously at week 8; or placebo. Change from baseline in Crohn's Disease Activity Index score (primary end point), clinical remission, clinical response, Patient Reported Outcomes-2 remission, clinical-biomarker response, endoscopic response (major secondary end points), and safety in guselkumab-treated patients vs placebo were evaluated through week 12. Ustekinumab was a reference arm.

RESULTS

Of 309 patients evaluated, approximately 50% had disease refractory to prior biologic therapy. At week 12, significantly greater reductions in Crohn's Disease Activity Index from baseline (least squares means: 200 mg: -160.4, 600 mg: -138.9, and 1200 mg: -144.9 vs placebo: -36.2; all, P < .05) and significantly greater proportions of patients achieved clinical remission in each guselkumab group vs placebo (Crohn's Disease Activity Index <150; 57.4%, 55.6%, and 45.9% vs 16.4%; all, P < .05). Greater proportions of patients receiving guselkumab achieved clinical response, Patient Reported Outcomes-2 remission, clinical-biomarker response, and endoscopic response at week 12 vs placebo. Efficacy of ustekinumab vs placebo was also demonstrated. Safety event rates were generally similar across treatment groups.

CONCLUSIONS

At week 12, all 3 dose regimens of guselkumab induced greater clinical and endoscopic improvements vs placebo, with a favorable safety profile.

CLINICALTRIALS: gov, Number: NCT03466411.