Spesolimab treatment for the prevention of flares in people with generalized pustular psoriasis (GPP): a plain language summary of the Effisayil™ 2 study

Generalized pustular psoriasis (shortened to GPP) is a rare, potentially life-threatening disease in which pus-filled blisters or pustules may suddenly form all over the body. The drug spesolimab has been approved to treat worsening GPP (known as flares) in many countries. However, it was not known if spesolimab could prevent the symptoms of GPP. This summary reports the results from a clinical study called Effisayil™ 2, that was done to understand if spesolimab was a safe and effective way to prevent flares in people with GPP. In the study, 123 participants, recruited in 20 different countries, were given one of three different doses of spesolimab (low, medium, or high) or a non-active medicine (placebo) over 48 weeks. Participants who received spesolimab had fewer GPP flares over the course of the 48-week study. Different doses of the drug were tested and compared to placebo, and a high dose of spesolimab worked better than low and medium doses. Using spesolimab also reduced the chance of developing skin symptoms, such as redness or pustules, and prevented quality of life getting worse over 48 weeks. While some participants experienced unwanted effects, they were mostly mild or moderate and most did not appear to be caused by spesolimab, or the dose at which it was given. The results indicate that a high dose of spesolimab works well to prevent GPP flares and stop the disease getting worse. Health authorities are looking at the results of this study to decide if spesolimab can also be prescribed for the prevention of GPP flares.