Extrapolating the speed of psoriasis clearance: Head-to-head agents in clinical trials.

Background: Biologic therapies targeting interleukin-17 (IL-17) and interleukin-23 (IL-23) pathways have transformed psoriasis management, with IL-17 inhibitors widely regarded as achieving faster clearance. However, the clinical significance of differences in clearance times remains unclear. Objective: To compare time to achieve a 75% reduction in the Psoriasis Area and Severity Index (PASI75) between IL-17 and IL-23 inhibitors using data from head-to-head clinical trials. Methods: A PubMed search identified trials reporting PASI75 response times for IL-17 and IL-23 inhibitors. Graphs from 12 studies were analyzed using Engauge Digitizer Software to estimate the time until half of participants reached PASI75. Results: IL-17 inhibitors achieved PASI75 faster than IL-23 inhibitors, with average response times of 4.5 weeks versus 7 weeks, respectively. The fastest IL-17 agent (bimekizumab) reached PASI75 in 2.5 weeks, while the fastest IL-23 agent (risankizumab) required 5.5 weeks. Differences between classes were smaller than anticipated, particularly for newer IL-23 inhibitors targeting the p19 subunit. Conclusion: IL-17 inhibitors generally achieve faster psoriasis clearance than IL-23 inhibitors, but the clinical relevance of this difference is limited. Safety and long-term efficacy profiles should guide treatment selection, highlighting the importance of personalized patient care.