AbbVie's SKYRIZI Demonstrates Superior Efficacy in Phase 3 Crohn's Disease Trial with Subcutaneous Induction
Key Insights
AbbVie (search)'s Phase 3 AFFIRM study showed risankizumab (SKYRIZI) subcutaneous induction achieved superior clinical remission rates of 55% versus 30% for placebo in moderately to severely active Crohn's disease (search) patients.
The study demonstrated significant endoscopic response rates of 44% versus 14% for placebo at week 12, with particularly strong results in a treatment-refractory population where 65% had failed advanced therapies.
Safety profile remained consistent with known risks, showing serious adverse events in only 0.5% of risankizumab patients compared to 3.1% in the placebo group.
AbbVie (search) announced positive topline results from its Phase 3 AFFIRM study evaluating subcutaneous risankizumab (SKYRIZI) as an induction treatment for adults with moderately to severely active Crohn's disease (search). The randomized, placebo-controlled, double-blind trial demonstrated superior efficacy across both co-primary endpoints at week 12, marking a significant advancement for patients with this challenging inflammatory bowel condition.
Strong Efficacy in Treatment-Refractory Population
The AFFIRM study enrolled 289 patients randomized in a 2:1 ratio to receive either risankizumab subcutaneous injection or placebo. Notably, the study population represented a predominantly treatment-refractory cohort, with 65% having failed advanced therapies for Crohn's disease (search) treatment. Among these patients, 50% had failed two or more advanced therapies, 23% had failed ustekinumab, and 12% had failed a Janus kinase inhibitor.
Risankizumab achieved significantly greater proportions of patients meeting the co-primary endpoints compared to placebo. For CDAI clinical remission (CDAI < 150), 55% of patients treated with risankizumab achieved this endpoint versus 30% with placebo (p<0.0001). For endoscopic response, 44% of risankizumab-treated patients achieved this outcome compared to 14% with placebo (p<0.0001).
"This study evaluated a difficult-to-treat Crohn's disease (search) patient population, including a majority with a prior failure to advanced therapy, and these data reinforce risankizumab as a leading, effective treatment for patients," said Kori Wallace, M.D., Ph.D., vice president, global head of immunology clinical development at AbbVie (search). "The level of endoscopic response is a particularly meaningful achievement for Crohn's disease patients; and for AbbVie, these results underscore our continued innovation and research to raise the standard of care."
Sustained Response Through Maintenance Phase
The study design included extended follow-up periods to assess sustained efficacy. Among patients who achieved clinical response after 12 weeks of risankizumab subcutaneous induction treatment followed by 12 weeks of maintenance therapy, 67% achieved CDAI clinical remission at week 24 and 57% achieved endoscopic response at week 24.
Lead investigator Millie D. Long, M.D., MPH, chief of the Division of Gastroenterology and Hepatology at the University of North Carolina, Chapel Hill, emphasized the clinical significance of these findings. "These high endoscopic response rates across populations, in particular among those who have not failed an advanced therapy, demonstrate the potential of subcutaneous induction risankizumab as an effective therapy for Crohn's disease (search)," she noted.
Favorable Safety Profile Maintained
During the 12-week, double-blind, placebo-controlled period, the safety profile of risankizumab subcutaneous injection remained consistent with the established safety profile observed in Crohn's disease (search), with no new safety risks identified. The most commonly reported adverse events among patients receiving risankizumab were upper respiratory tract infection, abdominal pain, and arthralgia.
Serious adverse events occurred in only 0.5% of patients in the risankizumab subcutaneous group compared to 3.1% in the placebo group, demonstrating a favorable safety margin for the active treatment.
Study Design and Methodology
The AFFIRM study represents a comprehensive evaluation structured across three treatment periods. Period A consisted of the placebo-controlled phase from baseline to week 12 to evaluate efficacy and safety of risankizumab subcutaneous induction treatment. Period B extended from week 12 to 24, where patients received blinded or open-label treatments based on their clinical response at week 12. Period C includes a 52-week open-label extension where all patients receive the approved risankizumab maintenance treatment.
Key demographics and baseline characteristics were generally balanced between the risankizumab subcutaneous and placebo groups, ensuring robust comparative analysis. The study's focus on a treatment-refractory population provides particularly valuable insights for clinical practice, as these patients represent some of the most challenging cases in Crohn's disease (search) management.
Clinical Context and Implications
Crohn's disease (search) is a chronic, systemic inflammatory condition affecting the gastrointestinal tract, most commonly between the small intestine and colon. The disease causes persistent diarrhea and abdominal pain, and its progressive nature means it typically worsens over time, potentially leading to life-threatening complications or requiring surgical intervention.
The unpredictable nature of Crohn's disease (search) symptoms creates significant burden for patients, affecting not only physical health but also emotional and economic well-being. The availability of subcutaneous induction therapy could provide patients and healthcare providers with additional treatment flexibility compared to intravenous administration options.
SKYRIZI (risankizumab) functions as an interleukin-23 (search) inhibitor that selectively blocks IL-23 (search) by binding to its p19 subunit. IL-23, a cytokine involved in inflammatory processes, is linked to various chronic immune-mediated diseases. The drug is currently approved by the U.S. Food and Drug Administration and European Medicines Agency for treating plaque psoriasis (search), psoriatic arthritis (search), Crohn's disease (search), and ulcerative colitis (search).
Full results from the AFFIRM study will be published in an upcoming medical journal and presented at future medical congresses, providing the medical community with detailed analysis of this important clinical trial data.