Ken Gordon, MD: Role of Placebo in the UltIMMa Trials

The UltIMMa trials of risankizumab demonstrated superior efficacy in treating moderate-to-severe plaque psoriasis compared to ustekinumab. However, the trials also included a placebo arm, intended to ground the results by blinding participants and investigators.

Ken Gordon, MD, Professor and Chair of Dermatology, Medical College of Wisconsin, Milwaukee, spoke with MD Magazine® about the role of placebo controls in trials like UltIMMa 1 & 2 at the 2019 Annual Meeting of the American Academy of Dermatology (AAD) in Washington, DC.

“What happens when you have a non-placebo-controlled trial is outcomes are better—everyone knows they're on active drug,” said Gordon. He added that a placebo arm need not extend the full length of the trial to provide the benefits of comparison.

Gordon was an author of the poster, “Efficacy and Safety of Risankizumab in Moderate-to-Severe Plaque Psoriasis: An Integrated Analysis of UltIMMa-1 and UltIMMa-2,” which was shared at the AAD Annual Meeting, held March 1-5, 2019. Here are part 1 and part 2 of his interview on the UltIMMa trials.

MD Mag: What is the role of placebo in trials like UltIMMa that compare 2 drugs?

Gordon: The placebo control is actually really, really important. A lot of the comparator trials that have been done most recently, in a sort of post-marketing approach, have been non-placebo-controlled trials. What happens when you have a non-placebo-controlled trial is outcomes are better—everyone knows they're on active drug. And it's human nature to know that the likelihood of a patient response is going to go up. So, to have placebo control is extremely important.

When you look at registry trials, the trials that are pre-approval, almost always you have to have a placebo arm in them. It's short, it's not the full 52 weeks—it's 16 weeks, but the fact that it's there actually grounds the data much more accurately than if you don't have a placebo arm. Even if it's a short placebo arm it really actually probably lends greater credence to the study versus some of the other trials that you look at, where they don't have placebo arm, that were done post-marketing.