A Phase II Multi Center Open Label Pilot Study To Assess a Potential Effect of an Anti-Il-1-Beta Antagonist in the Treatment of Pyoderma Gangrenosum

At the start of the study (week 0), all patients will receive one subcutaneous injection of 150mg Canakinumab. Patients are then going to be examined at weeks 2, 4, 8, 12 and 16.

At 2 weeks, all patients are going to be evaluated for response by Physician's global assessment (PGA) of the target lesion. Patients with PGA 0-1 are not going to receive another injection at this timepoint, while patients with PGA 2-4 are going to receive another 150mg Canakinumab.

At 4 weeks, in case of PGA 4, patients are going to be offered a first or second line drug as an alternative therapy (corticosteroids, cyclosporin A or infliximab, dosage see below "Alternative therapy in case of missing response") and stay within the trial (due to the long half-life of canakinumab) until week 8.

At week 8, patients with PGA 0 receive another 150mg Canakinumab only, and patients with PGA 4 are not going to receive additional study drug, but are strongly encouraged to attend following medical visits for observation until the end of the study and/or switch to a first or second line drug as alternative therapy (see below). All other patients with PGA 1-3 receive the total accumulative dose of Canakinumab that they had received on week 0 and 2, namely 150 or 300mg.

The study duration for each individual is going to be 16 weeks. At week 8 and 16, safety laboratory investigations with blood differential (Neutrophil granulocytes, monocytes, eosinophils, basophils, lymphocytes, thrombocytes, erythrocytes, hemoglobin), AST, ALT, y-GT, AP, Bilirubin (total), Creatinine, Na, K, CRP are going to be determined.