ClinicalTrials.gg
CompletedNCT03095885Updated Oct 28, 2021Results posted

A Pilot Study of Oxalate Absorption in Secondary Hyperoxaluria

An interventional study of Test Meal in Secondary Hyperoxaluria, Nephrolithiasis and Hyperoxaluria, sponsored by Allena Pharmaceuticals. Completed at 5 sites in United States. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2021-10-28.

Primary conditionKidney CalculiRegistry: NephrolithiasisReclassifiedWhy we changed it
Registry
Nephrolithiasis — the first condition term the registry derived for this study.
ClinicalTrials.gg
Kidney Calculi
Why
  1. The study's listed conditions name Kidney Calculi, a narrower term within Nephrolithiasis.
Confidence
High: the new condition is named in the study's own listed conditions. Of 351 hand-checked studies reclassified this way, 68% were exactly right and 84% in the right disease family; the registry's first term was right for 5% (measured 2026-10-21). How we classify →
Wrong?
Tell us the study's main condition →

Sponsored by Allena Pharmaceuticals · Not applicable, Interventional, and Basic science

From the registry’s dates

  • Registered 4 months after the study started (first participant enrolled Nov 2016, registered Mar 2017).
Phase
Not applicable
Study type
Interventional
Enrollment
22
Allocation
Not applicable
Ages
18 Years and older
Sex
All
01

Study summary

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

Read the 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).

02

Conditions studied

  • Secondary Hyperoxaluria
  • Nephrolithiasis
  • Hyperoxaluria
  • Kidney Stones

Keywords

  • Urine Oxalate
  • Nephrolithiasis
  • Kidney Stones
  • Hyperoxaluria
  • Enteric Hyperoxaluria
  • urological Diseases
  • Kidney Diseases
  • Dietary Oxalate
  • Idiopathic Hyperoxaluria
  • Oxalate Absorption
03

In context

Kidney Calculi Reclassified

509 studies on the registry are indexed under Kidney Calculi; 146 are open to participants now.

This study's enrollment of 22 is below the median of 86 across 391 interventional studies indexed under Kidney Calculi.

Browse Kidney Calculi studies →

Lead sponsor

Allena Pharmaceuticals is the lead sponsor of 12 studies on the registry; none are open to participants now.

Of its 9 completed or terminated interventional studies of FDA-regulated products, 0 (0%) have results posted.

Compared within Kidney Calculi, this study's primary condition as ClinicalTrials.gg classifies it; the registry's first condition term is Nephrolithiasis. The counts are of registry records indexed under each term, refreshed daily. How we classify →

04

Who can participate

Ages eligible
18 Years and older
Sexes eligible
All
Accepts healthy volunteers
No

Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.

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 .

Exclusion criteria

Exclusion Criteria:

  • Under or over-collection on screening 24-hour urine collection (mg creatinine/kg body weight outside of gender-specific range).
  • Estimated (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.
  • findings (including acute renal colic), an ongoing clinically significant illness requiring changes in management, or any planned medical/surgical procedure during the study.
  • undergoing active therapy; patients in remission on chronic suppressive or maintenance therapies are not excluded.
  • 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.
Terms in these criteria, in plain language(5)

Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.

Informed consent

Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.

You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.

GFR and eGFR (kidney filtering)

GFR (glomerular filtration rate) is how much blood the kidneys filter each minute. It is usually estimated from a blood test — eGFR, by formulas such as CKD-EPI or MDRD — and some studies ask for it to be measured directly instead. Usually given in mL/min/1.73 m².

Check the method, the units and the minimum the study states. A value of 90 or above is in the normal-or-high range, but kidney damage can show in other tests too.

Clinically significant

Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.

Cancer (malignancy)

Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.

Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.

Investigational drug or device

A drug or device being studied in a clinical trial.

It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.

05

Study design

Phase
Not applicable
Primary purpose
Basic science
Allocation
Not applicable
Intervention model
Single group
Masking
None (open label)
Enrollment
22 participants (actual)

Study arms

  • Other
    Test Meal

    controlled oxalate-rich test meal

    Other: Test Meal

Interventions

  • OtherTest Meal
06

What researchers measure

Primary outcomes

  1. Percent of Oxalate Absorption Normalized by Baseline Urinary Oxalate Excretion Over a 24 Hour Test Period

    Percent of oxalate absorption normalized by baseline was calculated by 100\*\[UOx/test - UOx/baseline\]/Ox intake from the test meal.

    Time frame: 24 hours during baseline and test day following oxalate-rich meal

Secondary outcomes

  1. Percent of Oxalate Absorption By Test Interval

    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.

    Time frame: 0-4 hours post test meal, 0-6 hours post test meal, 0-24 hours post test meal

  2. Percent Change From Baseline for Urinary Oxalate to Creatinine Ratio by Test Interval

    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.

    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

07

Results

Posted Mar 24, 2020

Participant flow

Participant flow — Overall Study
MilestoneTest Meal
Started22
Completed22
Not completed0

Outcome measures

PrimaryPercent of Oxalate Absorption Normalized by Baseline Urinary Oxalate Excretion Over a 24 Hour Test Period

Percent of oxalate absorption normalized by baseline was calculated by 100\*\[UOx/test - UOx/baseline\]/Ox intake from the test meal.

Time frame:
24 hours during baseline and test day following oxalate-rich meal
Reported as:
Mean · percentage of oxalate absorption
Percent of Oxalate Absorption Normalized by Baseline Urinary Oxalate Excretion Over a 24 Hour Test Period
percentage of oxalate absorptionTest Meal
Percent of Oxalate Absorption Normalized by Baseline Urinary Oxalate Excretion Over a 24 Hour Test Period2.84 ± 2.36
SecondaryPercent of Oxalate Absorption By Test Interval

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.

Time frame:
0-4 hours post test meal, 0-6 hours post test meal, 0-24 hours post test meal
Reported as:
Mean · percentage of oxalate absorption
Percent of Oxalate Absorption By Test Interval
percentage of oxalate absorptionTest Meal
0-4 Hours post test meal2.11 ± 0.52
0-6 hours post test meal3.55 ± 0.88
0-24 hours post test meal10.83 ± 3.04
SecondaryPercent Change From Baseline for Urinary Oxalate to Creatinine Ratio by Test Interval

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.

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
Reported as:
Mean · Percentage of change of UOx/Cr
Percent Change From Baseline for Urinary Oxalate to Creatinine Ratio by Test Interval
Percentage of change of UOx/CrTest Meal
0-4 hours post test meal68.17 ± 93.05
0-6 hours post test meal84.73 ± 100.05
6-24 hours post test meal45.39 ± 62
0-24 hours post test meal47.14 ± 64.82

Adverse events

Collected over 34 days (adverse events were recorded from the time of informed consent until the last study visit, and the screening period was approximately 30 days). Non-serious events are listed at a 5% frequency threshold.

Adverse event summary by group
GroupDeathsSeriousOther
Test Meal0/22 (0%)0/22 (0%)3/22 (13.6%)
Most frequent other events
Most frequent other events
EventTest Meal
ArthritisMusculoskeletal and connective tissue disorders1/22
Trigger fingerMusculoskeletal and connective tissue disorders1/22
HeadacheNervous system disorders1/22

Baseline characteristics

Age, Continuous
Age, Continuous(years)Enrolled Set
Mean57.3 ± 11.6
Sex: Female, Male
Sex: Female, Male(Participants)Enrolled Set
Female12
Male10
Race (NIH/OMB)
Race (NIH/OMB)(Participants)Enrolled Set
American Indian or Alaska Native0
Asian0
Native Hawaiian or Other Pacific Islander0
Black or African American2
White20
More than one race0
Unknown or Not Reported0
BMI (kg/m^2)
BMI (kg/m^2)(kg/m^2)Enrolled Set
Mean33.45 ± 8.04
Estimated glomerular filtration rate
Estimated glomerular filtration rate(mL/minute/1.73 /m^2)Enrolled Set
Mean80.7 ± 17.4
Hyperoxaluria Classification
Hyperoxaluria Classification(Participants)Enrolled Set
Idiopathic Hyperoxaluria17
Enteric Hyperoxaluria5
Number of Kidney Stone Episodes at Study Entry
Number of Kidney Stone Episodes at Study Entry(Episodes)Enrolled Set
Mean5 ± 5.37
08

Study locations

5 sites
  • Urological Associates of Southern Arizona, PC
    Tucson, Arizona 85741, United States
  • Applied Research Center of Arkansas, Inc.
    Little Rock, Arkansas 72212, United States
  • Regional Urology, LLC
    Shreveport, Louisiana 71106, United States
  • Omega Medical Research
    Warwick, Rhode Island 02886, United States
  • Urology of Virginia
    Virginia Beach, Virginia 23462, United States
09

References and documents

Individual participant data

Plan to share: No

No publications or documents are linked to this record.

10

Timeline

Tracking since Sep 25, 2026
ElapsedEstimatedEstimated, not yet reachedSimilar studies: half by the dot; the band is the middle halfHalf of similar studies reached it by the dot; the band is the middle half, from a quarter to three quarters

Ran from Nov 2016 to primary completion in Jan 2017, 2 months.

Results were first posted in Mar 2020, 3 years 2 months after primary completion.

Of 199 interventional studies with no phase under Kidney Calculi, half reached primary completion within 26 months of starting (the median), counting those still running; a quarter within 12 and three quarters within 51. This study's 2 months is below that.

How these figures are worked out, and which studies are left out of them.

Registered
Mar 20, 2017
First posted
Mar 30, 2017
StartActual
Nov 2016
Primary completionActual
Jan 2017
CompletionActual
Mar 2017
Results first posted
Mar 24, 2020
Last update
Oct 28, 2021
What these dates mean
Start.
When the first participant enrolled; while estimated, when the study expects to open to recruitment.
Primary completion.
When the last participant was examined or treated to collect data for the study's main question, its primary outcome. A study that stopped early gives the date its data collection stopped.
Completion.
When the last participant's last visit took place, for every outcome, secondary ones and side effects included: the end of the study. Often later than primary completion, sometimes the same day.
Actual and Est.
Actual means the registry says the date has happened. Est. (estimated) is a date the sponsor plans or expects. It can still move, and the sponsor is expected to change it to actual once it has passed.
No changes since tracking began. The registry record was last updated on Oct 28, 2021, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
11

Registry details

Key details

Study ID
NCT03095885
Lead sponsor
Allena Pharmaceuticals
Responsible party
Sponsor
First posted
Mar 30, 2017
Start date
Nov 2016
Primary completion
Jan 2017
Completion
Mar 2017
Results posted
Mar 24, 2020
Last update
Oct 28, 2021

Study contacts

Annamaria Kausz, MD, MS
study director · Allena Pharmaceuticals

Oversight

Data monitoring committee
No
View the source record on ClinicalTrials.gov ↗

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