SAN DIEGO -- More than half of patients with moderate-severe psoriasis treated with the investigational drug risankizumab achieved a PASI 100 response -- clear skin -- after a year of treatment, according to research presented here.
Investigators also found that patients treated with risankizumab achieved a PASI 100 response at 16 weeks in one of two double-blind placebo- and active-controlled phase III trials. For many of the study endpoints, the agent appeared superior to ustekinumab (Stelara) as well as to placebo.
Results from the two studies were presented by , of the Medical College of Wisconsin in Milwaukee, at the .
"In looking at a medication that gets 56% of patients in a clinical trial clear at one year -- that's a tremendous change in even how we think about treating patient," Gordon told , noting it wasn't too long ago that dermatologists were urged to not even try to get patients clear "because the hurdles were too great."
So, the idea of being able to get so many patients with psoriasis clear could represent a "fundamental change in patient care," Gordon said.
Risankizumab is a humanized IgG1 monoclonal antibody that binds to IL-23's p19 subunit, selectively inhibiting this critical cytokine and its role in psoriatic inflammation. It was evaluated in two phase III trials -- ultIMMa-1 and ultIMMa-2 -- which included ustekinumab as well as placebo as control therapies.
Patients were stratified by weight and prior TNF inhibitor exposure and randomized 3:1:1 to receive 150 mg risankizumab, 45/90 mg ustekinumab (weight-based per label) or matching placebo. Patients were dosed at weeks 0, 4, 16, 28, and 40, with placebo crossover to risankizumab at week 16. Co-primary endpoints were PASI 90 and sPGA 0/1 at week 16 versus placebo with comparisons between risankizumab and ustekinumab as ranked secondary endpoints.
During his presentation Gordon noted that both studies met the primary endpoints, as well as all 15 ranked secondary endpoints, including nine that compared risankizumab to ustekinumab. "This was an extremely high level of evidence for the efficacy of risankizumab," Gordon said.
He also pointed out that at 52 weeks 95% of patients managed to finish therapy. "I think that patient disposition is underestimated in importance in the looking at the efficacy of drug trials," Gordon said, adding that the 95% total in this study is "a high indicator of patient satisfaction with the clinical trial."
As for the results of the trial, 75.3% of patients in the ultIMMa-1 trial achieved PASI 90 response at week 16 compared to 42.0% of ustekinumab patients and 4.9% of placebo patients. The numbers were comparable in ultIMMa-2.
The sPGA clear or almost clear response was similar to the PASI 90 response, with risankizumab showing a superiority to ustekinumab at both 16 and 52 weeks.
PASI 100 responses at week 16 were 35.9% and 50.7% in the ultIMMa-1 and ultIMMa-2 trials, respectively. "Importantly, the differences in the two trials pretty much even out when you take it out through the year," Gordon said. "Up to 56.3% and 59% of patients treated for a year with risankizumab reached PASI 100."
Gordon also pointed out that 43.8% of patients in the ultIMMa-1 trial achieved a PASI 90 response at eight weeks. "This an extremely high level of response, which persisted for over a year," he said.
And the persistent response to the drug is also noteworthy, Gordon told . "For dermatologists, [plaque psoriasis] is a long-term disease, so anything we can do that can help us treat people effectively over time and maintain that effectiveness is really critical."
As for side effects, Gordon reported there were no new signals in the risankizumab group, which persisted into week 52.
The drug's developer AbbVie, along with collaborator Boehringer Ingelheim, expect regulatory approval of the drug this year, with commercialization to follow in 2019.
"When you think about a drug like this and how it demonstrates a high level of response, you really start to think about what we can do when the drug actually becomes available to our patients in the clinic," Gordon said.
Disclosures
Gordon reported relationships with AbbVie, Amgen, Lilly, Boehringer Ingelheim, Demira, Celgene, Bristol-Myers Squibb, Janssen, Novartis, Merck & Co., UCM, and Sun Pharmaceuticals.
Primary Source
American Academy of Dermatology
Gordon K, et al "Efficacy and safety of risankizumab: Results from two double-blind, placebo- and ustekinumab-controlled, phase 3 trials in moderate-to-severe plaque psoriasis" AAD 2018