A Pilot Study of Oxalate Absorption in Secondary Hyperoxaluria

• ClinicalTrials.gov Identifier: NCT03095885
• Recruitment Status: Completed
• First Posted: March 30, 2017
• Results First Posted: March 24, 2020
• Last Update Posted: October 28, 2021
• Sponsor: Allena Pharmaceuticals
• Information provided by (Responsible Party): Allena Pharmaceuticals

Study Description

Brief Summary:

Identify individuals with greater absorption of oxalate based on increase in urinary oxalate excretion in response to a controlled oxalate-rich test meal.

Condition or disease	Intervention/treatment	Phase
Secondary Hyperoxaluria; Nephrolithiasis; Hyperoxaluria; Kidney Stones	Other: Test Meal	Not Applicable

Detailed Description:

This was a prospective 4-day study of oxalate absorption in subjects with secondary hyperoxaluria. Subjects visited the research center three times for outpatient visits (Screening, Test Day 3, Day 4).

Subjects were instructed to follow a low-oxalate diet, consuming only study-specified food choices that had low or no oxalate and controlled calcium content Days 1 through 4 (Baseline Period through the Day 4 clinic visit) and, on Test Day 3, consumed an oxalate-rich test meal.

Subjects performed three 24-hour urine collections during Screening, Baseline Day 2, and Test Day 3. Test Day 3 included the oxalate-rich test meal and the subject collected a 24-hour urine separated into 4 urine collection intervals. (Pre-test meal, post-test meal to 4 hours, 4-6 hours post test meal and remaining time to complete 24 hours).

Study Design

• Study Type: Interventional (Clinical Trial)
• Actual Enrollment: 22 participants
• Allocation: N/A
• Intervention Model: Single Group Assignment
• Masking: None (Open Label)
• Primary Purpose: Basic Science
• Official Title: A Pilot Study of Oxalate Absorption in Secondary Hyperoxaluria
• Actual Study Start Date: November 2016
• Actual Primary Completion Date: January 2017
• Actual Study Completion Date: March 2017

Arms and Interventions

Arm	Intervention/treatment
Test Meal; controlled oxalate-rich test meal	Other: Test Meal

Outcome Measures

Primary Outcome Measures :

1. Percent of Oxalate Absorption Normalized by Baseline Urinary Oxalate Excretion Over a 24 Hour Test Period [ Time Frame: 24 hours during baseline and test day following oxalate-rich meal ]
   Percent of oxalate absorption normalized by baseline was calculated by 100*[UOx/test - UOx/baseline]/Ox intake from the test meal.

Secondary Outcome Measures :

1. Percent of Oxalate Absorption By Test Interval [ Time Frame: 0-4 hours post test meal, 0-6 hours post test meal, 0-24 hours post test meal ]
   Percent of Oxalate absorption by test interval was calculated as the urinary oxalate excretions (mg) during the test interval divided by the amount of oxalate in the test meal.
2. Percent Change From Baseline for Urinary Oxalate to Creatinine Ratio by Test Interval [ Time Frame: 24 hours during baseline, 0 to 4 hours post test meal, 0-6 hours post test meal, 6-24 hours post test meal, 0-24 hours post test meal ]
   Urinary oxalate (UOx) excretion was normalized to units of mg/g creatinine by dividing the UOx in mg by the creatinine value in g from the same collection. Percent change from baseline for UOx/Cr from Baseline was calculated by 100 * [UOx/Cr for the test interval - UOx/Cr at Baseline] / UOx/Cr at Baseline.

Eligibility Criteria

• Ages Eligible for Study: 18 Years and older (Adult, Older Adult)
• Sexes Eligible for Study: All
• Accepts Healthy Volunteers: No

Criteria

Inclusion Criteria:

• Males or non-pregnant and non-lactating females
• History of hyperoxaluria secondary to a known underlying enteric disease (e.g., Crohn's disease, bariatric surgery, and others) or without a known underlying cause (idiopathic), and kidney stones.
• Urinary oxalate ≥ 40 mg of oxalate/24 hr at screening.
• If taking drugs for the prevention of stone disease, including pyridoxine, thiazides (chlorthalidone, hydrochlorothiazide, and indapamide), citrate supplements, and allopurinol, there must have been no changes in these medications for at least one month prior to screening and no changes are anticipated for the duration of the study.
• Able to understand and provide written informed consent.

Exclusion Criteria:

• Under or over-collection on screening 24-hour urine collection (mg creatinine/kg body weight outside of gender-specific range).
• Estimated glomerular filtration rate (eGFR) <40 mL/minute/1.73 m^2 or acute renal failure.
• Primary hyperoxaluria.
• Allergy, intolerance, or any other factors limiting ability to consume the study foods or adhere to the study meal schedule.
• Positive pregnancy test during Screening.
• Clinically significant findings (including acute renal colic), an ongoing clinically significant illness requiring changes in management, or any planned medical/surgical procedure during the study.
• Malignancy undergoing active therapy; patients in remission on chronic suppressive or maintenance therapies are not excluded.
• Investigational compound within 30 days prior to screening.
• Investigator determined that the subject would not be able to adhere or to complete the study procedures , or could not discontinue Vitamin C supplements, calcium supplements, or other medications that could interfere with oxalate absorption and/or excretion.

Contacts and Locations

Locations

United States, Arizona

Urological Associates of Southern Arizona, PC

Tucson, Arizona, United States, 85741

United States, Arkansas

Applied Research Center of Arkansas, Inc.

Little Rock, Arkansas, United States, 72212

United States, Louisiana

Regional Urology, LLC

Shreveport, Louisiana, United States, 71106

United States, Rhode Island

Omega Medical Research

Warwick, Rhode Island, United States, 02886

United States, Virginia

Urology of Virginia

Virginia Beach, Virginia, United States, 23462

Sponsors and Collaborators

Allena Pharmaceuticals

Investigators

• Study Director: Annamaria Kausz, MD, MS; Allena Pharmaceuticals

More Information

• Responsible Party: Allena Pharmaceuticals
• ClinicalTrials.gov Identifier: NCT03095885
• Other Study ID Numbers: ALLN-177-204
• First Posted: March 30, 2017
• Results First Posted: March 24, 2020
• Last Update Posted: October 28, 2021
• Last Verified: October 2021

Individual Participant Data (IPD) Sharing Statement:

• Plan to Share IPD: No

Keywords provided by Allena Pharmaceuticals:

Urine Oxalate; Nephrolithiasis; Kidney Stones; Hyperoxaluria; Enteric Hyperoxaluria; urological Diseases; Kidney Diseases; Dietary Oxalate; Idiopathic Hyperoxaluria; Oxalate Absorption

Additional relevant MeSH terms:

Neoplasm Metastasis; Kidney Calculi; Nephrolithiasis; Hyperoxaluria; Neoplastic Processes; Neoplasms; Pathologic Processes; Kidney Diseases; Urologic Diseases; Urolithiasis; Urinary Calculi; Calculi; Pathological Conditions, Anatomical