A Phase 3 Clinical Trial of Intravenous Sodium Thiosulfate in Acute Calciphylaxis Patients

Inclusion Criteria: * Informed of the investigational nature of the study and sign written informed consent * Willing and able to adhere to all study-related procedures, including adherence to study medication regimen * Male or female ≥18 years old * End-stage renal disease on chronic hemodialysis * Calciphylaxis with active skin lesion(s) of any morphological appearance (including but not limited to livedo, induration, ulceration, etc.) and tissue histology review consistent with calciphylaxis diagnosis. Histological features consistent with calciphylaxis will include soft tissue calcification, microthrombosis, and/or fibrointimal hyperplasia of dermal arterioles * Acute pain associated with calciphylaxis lesions pain intensity score of ≥ 5 at initial screening on the modified BPI/SF scale * Women of childbearing potential must have a pregnancy test (urine or serum \[if anuric\]) at screening and not be pregnant and willing to use an acceptable method of contraception for the entire duration of the study (3 weeks) Exclusion Criteria: * Peritoneal dialysis patients * Current congestive heart failure exacerbation * Baseline abnormalities related to QT prolongation (corrected QT interval \> 470 ms), hypocalcemia (serum albumin-corrected calcium \< 8 mg/dL ), metabolic acidosis (serum bicarbonate \< 18 mmol/L, hypotension (resting systolic blood pressure while seated \< 80), or interdialytic weight gain ≥ 4.0 kg * History of ventricular arrhythmias including ventricular fibri…