Inclusion Criteria:

• Calciphylaxis with at least one ulcerated or necrotizing lesion
• End stage renal disease requiring hemodialysis
• Weight superior to 30kg
• Subject affiliated to or beneficiary of a social security system
• Subject having signed written informed consent

A patient with progressing calciphylaxis to ulcerate or necrosis despite conventional treatment may also be included.

Exclusion Criteria:

• KARNOFSKY Performance Status Scale inferior to 30%
• Life expectancy (independently of calciphylaxis) estimated < 6 months according to a referring physician expert in hemodialysis
• Uncontrolled infection (persistence of fever despite appropriate antibiotic therapy)
• Common variable immunodeficiency
• Albumin allergy
• Contra-indication to stop anti-vitamin K treatment
• Severe cognitive or psychiatric disorders, patients unable to give an informed consent or unwilling to participate in the study
• Pregnancy or breastfeeding and all the other categories of people with special protection according to the French Code de la Santé Publique (CSP): patients under legal supervision, patients hospitalized without contentment, patients admitted in social or sanitary structures for care and not research, and patients in emergency situations.