Phase 3 Study of SNF472 for Calciphylaxis

Inclusion Criteria: * Female or male subjects, 18 years of age or older * Receiving maintenance HD in a clinical setting for at least 2 weeks prior to screening * Clinical diagnosis of CUA by the Investigator including ≥1 CUA lesion with ulceration of the epithelial surface * CUA wound-related pain shown by a Pain VAS score ≥50 out of 100 * Primary lesion that can be clearly photographed for the purpose of protocol-specified wound healing assessments. * Willing and able to understand and sign the informed consent form and willing to comply with all aspects of the protocol Exclusion Criteria: * History of treatment with bisphosphonates within 3 months of baseline * Severely ill subjects without a reasonable expectation of survival for at least 6 months * Subjects with a scheduled parathyroidectomy during the study period * Expectation for kidney transplant within the next 6 months based on Investigator assessment or identification of a known living donor * Pregnant or trying to become pregnant, currently breastfeeding, or of childbearing potential (including perimenopausal women who have had a menstrual period within one year) and not willing to comply with protocol required contraception criteria * Significant noncompliance with dialysis * History of active malignancy within the last year with the exception of localized basal cell or squamous cell carcinoma * Clinically significant illness other than CUA within 30 days * Participation in an investigational study and receipt of an investigational drug or investigational use of a licensed drug within 30 days prior to screening. * History or presence of active alcoholism or drug abuse as determined by the Investigator within 6 months * Mental impairment, current significant psychiatric disease, or other conditions or circumstances that would make the subject unlikely to complete the study or comply with the study procedures. * Subjects whose CUA lesions exhibit significant improvement, in the opinion of the Investigator, between the first and second screening visit