Oxazyme in Patients With Hyperoxaluria

Mayo Clinic

Status and phase: Completed; Phase 2; Phase 1

Conditions: Hyperoxaluria

Treatments: Drug: Oxazyme

Study type: Interventional

Funder types: Other; Industry

Identifiers

NCT01127087

10-000676

Details and patient eligibility

About

Hypothesis: Oral administration of the oxalate metabolizing enzyme Oxazyme (OC4) will degrade food-borne oxalate and hence prevent its absorption from the gastrointestinal tract. In addition, by reducing oxalate concentrations in the gastrointestinal fluid, oxalate secretion from blood to the intestinal tract may be increased. Both effects would decrease blood levels of oxalate, and hence oxalate excretion in the urine.

Full description

Oxazyme is an oxalate degrading compound that can potentially degrade food-borne oxalate and hence prevent its absorption from the gastrointestinal tract.

We propose a 20-patient open-label trial pilot study of one month of Oxazyme twice daily (1gm Oxazyme sachet dissolved in 150 ml water) among adult subjects with a history of calcium oxalate nephrolithiasis. Patients will be stratified into those with enteric hyperoxaluria after Roux-en-Y Gastric Bypass (RYGB, n=10) and those with idiopathic hyperoxaluria (n=10). The patients will perform two, 24-hour, urine collections immediately before starting Oxazyme and on the last two days of the treatment period.

Enrollment: 22 patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Roux-en-Y gastric bypass hyperoxaluric Calcium oxalate (CaOx) stone subjects or Idiopathic hyperoxaluric CaOx stone subjects
• Patients must have or had radio-opaque stones present on x-ray, or a history consistent with the passage of a stone or stone surgery or Extracorporeal Shock Wave Lithotripsy (ESWL) in the last 5 years.
• Hyperoxaluria Ox/Cr ratio ≥36 mg/g
• The patient must be able to provide written informed consent
• Patients must be able to urinate reliably into a collection vessel to measure urine volume.
• Patients may be taking drugs for the prevention of stone disease, including pyridoxine, thiazides, citrate supplements and allopurinol, as long as there have been no changes in these medications for at least 3 months

Exclusion criteria

• Primary hyperoxaluria patients
• Use of Oxadrop, Oxabsorb, or other therapies affecting oxalate absorption from the gut, other than stable doses of calcium.
• Subjects who are pregnant. Women of childbearing potential must have a negative pregnancy test prior to enrollment and must practice some form of birth control during the trial.
• Patients on an unstable dose of any other drugs for the prevention of stone disease (i.e., pyridoxine, citrate supplements. etc.). Patients should have been on a stable dose for at least 3 months prior to randomization.

Trial design

Primary purpose: Treatment

Allocation: Non-Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

---

22 participants in 2 patient groups

RYGB CaOx Stone Formers

Experimental group

Description:

Subjects with enteric hyperoxaluria after Roux-en-Y Gastric Bypass (RYGB). Dosing: 1gm Oxazyme containing approximately 1600 Units OxDC in a sachet administered BID together with lunch and dinner. Subjects were instructed to open the oxazyme sachets and either sprinkle on food or add to a glass of water or fruit juice and consume the contents with a meal twice daily.

Treatment:

Drug: Oxazyme

Idiopathic Hyperoxaluria CaOx Stone Formers

Experimental group

Description:

Subjects with idiopathic hyperoxaluria. Dosing: 1gm Oxazyme containing approximately 1600 Units OxDC in a sachet administered BID together with lunch and dinner. Subjects were instructed to open the oxazyme sachets and either sprinkle on food or add to a glass of water or fruit juice and consume the contents with a meal twice daily.

Treatment:

Drug: Oxazyme