Evaluating ALLN-177 for Reducing Urinary Oxalate Excretion in Calcium Oxalate Kidney Stone Formers With Hyperoxaluria

Inclusion Criteria: * Able to provide informed consent * Able to comply with study procedures * History of enteric or idiopathic hyperoxaluria and at least one calcium oxalate kidney stone * Hyperoxaluria \>36mg of oxalate/24-hr * May be taking drugs for the prevention of stone disease as long as there have been no changes in these medications for at least 3 months Exclusion Criteria: * Uric acid ≥1.5g/24-hr * Estimated glomerular filtration rate of \< 60 mL/min * Positive results from drug urine screen * Requires daily vitamin C (defined as \>10 days of \>300 mg/day) * Diagnosis of hypercalcemia or hypothyroidism * Obstructive uropathy, chronic urosepsis, renal failure, renal tubular acidosis, primary hyperparathyroidism, primary hyperoxaluria, pure uric acid and cystine stones, and/or medullary sponge kidney. * Auto-immune disorder requiring high dose steroids or other immunosuppressant drugs. * Subjects who are pregnant. Women of childbearing potential must have a negative pregnancy test prior to enrollment and must practice approved methods of birth control during the trial * History of cancer diagnosis except for within the past 5 years excluding dermal squamous and/or basal cell carcinoma or cervical carcinoma in situ. * Taken investigational compound within 30 days prior to the first day of the study * Treatment with cholestyramine * Average daily dietary intake of \<75 mg oxalate per day calculated from diet recalls