L-17 vs IL-23: Head-to-Head Data in Psoriasis and PsA

In "IL-17 vs IL-23: Head-to-Head Data in Psoriasis and PsA," our experts turn to the trials clinicians actually reach for when choosing a class.

Dr. Wright explains that useful comparisons require head-to-head trials in the same patient population. Most head-to-heads in psoriatic disease were done in psoriasis, with adalimumab as a frequent comparator, so many IL-17 and IL-23 agents beat adalimumab on skin. She introduces BE BOLD as a more recent trial pitting an IL-17AF agent against an IL-23 agent on joint-specific measures.

Dr. Wright stresses that comorbidity drives the real-world choice. A patient with psoriatic arthritis plus uveitis or inflammatory bowel disease may not be able to take an IL-17, even if it would serve their skin and joints best. She frames this as thinking across the domains in which psoriatic disease disrupts a patient's life, and welcomes that these agents carry approvals in Crohn's and ulcerative colitis too.

Dr. Han turns to the skin, where nearly every newer medication now sits above adalimumab, though less so on joints. He cautions that nobody runs a trial they expect to lose. He traces the steady rise in mean PASI improvement from about 70% with etanercept, to roughly 75 to 80% with adalimumab and ustekinumab, up to 90 to 95% across the IL-17 and IL-23 classes. He notes that IL-23 versus IL-17 trials often pick secukinumab, the oldest of the newer agents, and choose time points that favor the sponsor, since IL-17s tend to act faster.

Dr. Han argues speed matters to patients even if the difference is measured in weeks, since survey studies show patients value onset. He calls for more special-site comparative trials, citing secukinumab besting ustekinumab on scalp psoriasis as the kind of data clinicians need for scalp, palmoplantar, inverse, and nail disease.

Up next, in "Exploring the IL-17 vs IL-23 Debate in Psoriasis," the panel asks whether the IL-17 versus IL-23 debate is settled, and finds the answer depends heavily on the individual patient.