A Study to Test Whether Spesolimab Helps People With Generalized Pustular Psoriasis (GPP) Who Need Treatment for Repeated Flares

This study is open to adults with a serious skin disease called generalized pustular psoriasis (GPP) who have repeated flares of GPP. The purpose of this study is to find out whether a medicine called spesolimab helps people with repeated flares of GPP. Participants are given a single dose of spesolimab as an infusion into a vein on the first day of an outbreak of GPP. They may be given a second dose 1 week later if doctors think it is helpful. They are also treated for additional GPP flares. During the time of the study, doctors regularly examine participants' skin for signs of GPP to see how well the treatment works and take blood samples. The doctors also regularly check participants' health and take note of any unwanted effects.