Extended risankizumab treatment for Crohn’s disease

Extended risankizumab (RZB) therapy has shown promising results for Crohn’s disease patients who fail to respond to the standard 12-week induction phase. Phase 3 trials (ADVANCE, MOTIVATE, FORTIFY) evaluated the efficacy of an additional 12 weeks of RZB treatment, administered intravenously (1200 mg) or subcutaneously (180 mg or 360 mg). Among initial nonresponders, over 60% achieved stool frequency/abdominal pain score (SF/APS) clinical response by week 24, while 43–45% attained clinical remission. Endoscopic response or remission was observed in 32–40% of patients by week 24, highlighting mucosal healing.

Delayed responders maintained these benefits during the maintenance phase, with clinical response rates of 56.7% (180 mg SC) and 69.7% (360 mg SC) persisting through week 52. Endoscopic remission continued or improved, demonstrating sustained mucosal healing. Higher efficacy was observed with the 360 mg SC dose compared to 180 mg SC during maintenance. Combining early and delayed responders, total clinical response reached 89.1%, emphasizing the cumulative benefit of extended therapy.

Predictive factors for delayed response included older age and prior failure of more than one biologic therapy. Despite 75% of patients being highly treatment-experienced, the majority benefited from extended RZB therapy. Safety data revealed a well-tolerated profile, with mild hypersensitivity and injection site reactions as the most common adverse events. Serious adverse events were rare, and no new safety concerns emerged.

The study concluded that extending RZB therapy is effective in recapturing delayed responders, offering sustained clinical and endoscopic remission for Crohn’s disease patients, even in difficult-to-treat populations.