Phase III Trial to Investigate Efficacy and Safety of Vilobelimab in Ulcerative Pyoderma Gangrenosum

Main Inclusion Criteria:

1. 18 years or older at the time of signing the informed consent.

2. Investigator confirmed clinical diagnosis of ulcerative PG. Diagnosis shall besupported by clinical assessment of PG symptoms via PARACELSUS score (Jockenhofer,Wollina et al. 2019) of 10 points or more (see Appendix - Section 12.1). Note: incase of PARACELSUS score < 10, additional justification shall be provided by theinvestigator to support clinical diagnosis of ulcerative PG.

3. Minimum of 1 evaluable PG ulcer (other than peristomal) which qualifies as thetarget ulcer by meeting the following criteria (Orfaly, Reese et al. 2022): area of ≥ 5 cm 2 at screening and baseline

• circulated by intact skin

• evaluable by at least 2-dimensional measurement

Main Exclusion Criteria:

1. Patients with target ulcers exceeding 80 cm 2 .

2. Patients with target ulcer in transplanted skin.

3. Surgical wound debridement or negative pressure wound therapy (NPWT) for the targetulcer within 4 weeks before baseline (i.e., start of treatment with IMP).

4. Patient with previous exposure to vilobelimab (IFX-1) prior to baseline (i.e., startof treatment with IMP).

5. Patient receives/has received a vaccine within 2 weeks prior to baseline (i.e.,start of treatment with IMP).

6. Any active infection requiring systemic antibiotic or other systemic treatment orsuppressive anti-infective therapy within 2 weeks prior to baseline (i.e., start oftreatment with IMP).

7. Patients received any systemic medical treatment for PG within 4 weeks prior tobaseline

8. Patients received any biological or immunomodulatory therapy for PG within 4 weeksprior to baseline (i.e., start of treatment with IMP), except existing biologic orimmunomodulatory therapy used for an underlying disease (other than PG at a stabletherapy with no dose adjustments for at least two maintenance doses prior toscreening this is allowed to be continued.

9. Patients receiving corticosteroids treatment for PG of more than 10 mg/day ofprednisone or equivalent within 4 weeks prior to baseline (i.e., start of treatmentwith IMP).