SAN DIEGO – Risankizumab outperformed ustekinumab in two phase 3 trials investigating the IL-23 blocker for moderate to severe plaque psoriasis.
In two year-long studies, 56% and 59% of those taking risankizumab and 21% and 30% of those taking ustekinumab achieved completely clear skin, Kenneth B. Gordon, MD, said at the annual meeting of the American Academy of Dermatology.
Bruce Jancin/Frontline Medical News
Dr. Kenneth B. Gordon
“One of the things we are striving for now is complete skin clearance,” said Dr. Gordon, chair of the dermatology department the Medical College of Wisconsin, Milwaukee. “In the past, people have said that it wasn’t important to reach that, yet here we are, getting more than 50% of patients to that point.”
Risankizumab is an investigational monoclonal antibody that selectively blocks IL-23, a key inflammatory protein. The drug is also in phase 3 trials for Crohn's disease, and being investigated for psoriatic arthritis. AbbVie, which is developing risankizumab, plans future trials for treating ulcerative colitis.
Dr. Gordon reported the results of UltIMMa-1 and UltIMMa-2, identical three-armed studies that randomized a total of 797 patients with moderate to severe plaque psoriasis to risankizumab 150 mg, ustekinumab 45 mg or 90 mg (based on weight), or to a crossover group that took placebo for the first 16 weeks of the study and then were switched to risankizumab 150 mg for the remainder of the study. Study drugs were delivered at weeks 0, 4, 16, 28, and 40.
The coprimary endpoints were at least a 90% improvement in the Psoriasis Area Severity Index score (PASI 90) at week 16 and a score of 0 or 1 on the Static Physicians’ Assessment scale (sPGA 0/1) at week 16, compared with placebo. Key secondary endpoints compared risankizumab with ustekinumab: PASI 90, sPGA score of clear (sPGA 0), sPGA 0/1, and Dermatology Quality of Life (DLQI) score of 0/1 at week 16, and PASI 90, PASI 100 and sPGA 0 at week 52.
In both trials, patients were 48 years old on average; about 20% had severe plaque psoriasis. The mean PASI score was about 20 at trial entry. Prior therapy included biologics in 30%-43%, depending on the trial, and TNF-alpha inhibitors in about 25%.
Patient retention in the study was good, Dr. Gordon noted, with 95% of risankizumab patients still taking the drug at 52 weeks. Patients also stayed on ustekinumab, with 94% of UltIMMa-1 patients and 91% of UltIMMa-2 patients still taking the drug at 52 weeks.
At week 16, risankizumab was clearly superior to placebo in both endpoints. In both studies, 75% of actively treated patients achieved PASI 90, compared to 5% of those taking placebo. In UltIMMa-1, a clear or almost clear sPGA was seen in 88% of risankizumab patients as compared to 8% of those taking placebo. In UltIMMa-2, these numbers were 84% and 5%, respectively.
In the secondary comparison of the two active drugs, risankizumab significantly outperformed ustekinumab on PASI90 at 16 weeks in UltIMMa-1 (75% vs. 42%) and in UltIMMa-2 (75% vs. 47%). The PASI90 outcomes similarly favored risankizumab at 52 weeks in UltIMMa-1 (82% vs. 44%) and in UltIMMa-2 (81% vs. 50%).