ClinicalTrials.gg
RecruitingNCT02890342Updated Nov 9, 2026

Natural History, Physiology, Microbiome and Biochemistry Studies of Propionic Acidemia

An observational study in Metabolic Disease, Propionic Acidemia and Organic Acidemia, sponsored by National Human Genome Research Institute (NHGRI). Recruiting at 2 sites in United States. Open to participants aged 1 Month to 100 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-11-09.

Primary conditionPropionic AcidemiaRegistry: Metabolic DiseasesReclassifiedWhy we changed it
Registry
Metabolic Diseases — the first condition term the registry derived for this study.
ClinicalTrials.gg
Propionic Acidemia
Why
  1. The study's listed conditions name Propionic Acidemia, a narrower term within Metabolic Diseases.
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 National Human Genome Research Institute (NHGRI) · Observational

From the registry’s dates

  • Started Nov 2016; still recruiting 9 years 11 months later.
Study type
Observational
Model
Cohort
Time perspective
Prospective
Enrollment
1,045
Ages
1 Month to 100 Years
Sex
All
01

Study summary

Background:

People s bodies need to break down food into the chemicals. These chemicals are used for energy and growth. Some people cannot process all chemicals very well. Too much of some chemicals can cause diseases. One of these diseases is called propionic acidemia (PA). People with PA can have problems with growth, learning heart, abdomen, and other organs. Researchers want to better understand how these problems happen.

Objective:

To learn more about propionic acidemia and the genes that might contribute to it.

Eligibility:

People at least 2 years old with PA who can travel to the clinic

Some unaffected family members

Design:

Participants will have a 3 to 5-day hospital visit every year or every few years. Family members may have just 1 visit.

During the family member visit, they may have:

Medical history

Physical exam

Samples of blood and urine

Questions about diet and a food diary

Doctors and nurses may do additional studies:

Samples of saliva, skin and stool

Fluid from a gastronomy tube, if participants have one

Dental and eye evaluations

A kidney test - a small amount of dye will be injected and blood will be collected.

Consultations with specialists

A test of calories needed at rest. A clear plastic tent is placed over the participant to measure breathing.

Stable isotope study. Participants will take a nonradioactive substance then blow into a bag.

Photos taken of the face and body with underwear on

Ultrasound of the abdomen

Heart tests

Hand x-ray

Brain scan

Participants may have other tests if study doctors recommend them. They will get the results of standard medical tests and genetic tests.

...

Read the detailed description

Propionic acidemia (PA) is one of the most common inborn errors of organic acid metabolism. Although this disorder is now routinely detected in the immediate neonatal period on the US newborn screen, clinical outcomes are poor despite timely and aggressive medical intervention. Worldwide, the incidence of PA varies widely. The estimated live-birth incidence of PA is 1:243,000 in the US, 1:166,000 in Italy and 1:250,000 in Germany. Affected patients are medically fragile and can suffer from complications such as failure to thrive, intellectual disability, basal ganglia strokes, seizures, cardiomyopathy, cardiac arrhythmias, pancreatitis, impaired gut motility, osteoporosis and hematological complications. The frequency of these complications in the US patients and their precipitants remain poorly understood. Furthermore, current treatment outcomes have continued to demonstrate substantial morbidity and mortality in the patient population. Specific treatments include dietary modification to reduce propiogenic precursor load, levocarnitine to facilitate excretion of propionate, and oral antibiotics to suppress propionogenic gut flora. More recently, solid organ transplantation (liver and/or kidney) has been used to treat PA patients experiencing frequent and severe episodes of metabolic instability. However, optimal transplant strategy and post-transplant management have not been delineated. Several survey-based and retrospective studies describing the natural history of propionic acidemia have been published in the last decade. While these publications added to our understanding of the clinical course of this disease, these studies have not systematically focused on the US population using prospective analysis and reflect largely European experience, where many developed countries do not routinely screen for PA using newborn screen. Thus, the benefits of newborn screening on the PA outcomes require further clarification.

Under proposed NIH protocol, we will prospectively evaluate patients with propionic acidemia with special emphasis on the US population. Typical inpatient admissions and outpatient evaluations will last up to 4-5 days and may involve blood drawing, urine collection, stool collections, genomic studies, ophthalmological examination, cardiology evaluation, radiological procedures, brain and cardiac MRI/MRS, dietary assessment and neurobehavioral evaluation. In some patient s skin biopsies will be pursued.

The study objectives will be to describe the natural history of propionic acidemia in the US patients by delineating the spectrum of phenotypes and querying for genotype, enzymology, microbiome, and phenotype correlations. The population will consist of patients previously evaluated at NIH, physician referrals, and families directed to the study from clinicaltrials.gov, Organic Acidemia Association and Propionic Acidemia Foundation. Patients will be evaluated at the NIH Clinical Center or via telehealth platforms supported by NIH. Outcome measures will largely be descriptive and encompass correlations between clinical, microbiological, biochemical and molecular parameters.

02

Conditions studied

  • Metabolic Disease
  • Propionic Acidemia
  • Organic Acidemia

Browse trials for

Keywords

  • Organic Acidemia
  • Inborn Errors of Metabolism
  • Natural History
03

In context

Propionic Acidemia Reclassified

23 studies on the registry are indexed under Propionic Acidemia; 8 are open to participants now.

This study's planned enrollment of 1,045 is above the median of 78 across 10 observational studies indexed under Propionic Acidemia.

Browse Propionic Acidemia studies →

Lead sponsor

National Human Genome Research Institute (NHGRI) is the lead sponsor of 203 studies on the registry; 33 are open to participants now.

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

04

Who can participate

Ages eligible
1 Month to 100 Years
Sexes eligible
All
Accepts healthy volunteers
Yes
Sampling method
Non-probability sample

Study population

Patients with Propionic Acidemia

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

  • Patients 2 years of age or older, of any gender and ethnicity, with propionic acidemia are eligible to enroll in this protocol. Patients diagnosis will be confirmed based on biochemical and/or molecular and enzymatic testing. Participants of any gender and ethnicity over 1 month of age are eligible to enroll remotely for collection of outside records and natural history data. They will be eligible to enroll in the full study for in-person evaluation at 2 years of age.
  • Unaffected family members over 1 month of age, of any ethnicity or race, may be included in the study as household controls for microbiome studies and/or for genetic analysis. Studies in unaffected family members may include collection of medical and family history; if necessary completion of physical examination; drawing of blood for research purposes include testing of DNA; collection of stool samples for microbiome studies; collection of dietary history using pen-and-paper or electronic food diary and questionnaires; collection of saliva for metabolite and DNA analysis. In some unaffected family members without a known familial cause of propionic acidemia, exome sequencing or genome sequencing could be performed. Unaffected family members will not receive direct benefit from taking part in the study.
  • If a participant becomes pregnant while on study, the participant can remain on study. The only way to learn more about the critical biological differences in those who affected with propionic acidemia who are pregnant is to continue to follow pregnant women on study.

However, no tests or procedures that are greater then minimal risk will be performed. Affected subjects who are pregnant may undergo procedures as part of their clinical care, including blood draws, genetic studies, and consultations, according to the clinical judgement of the clinical team. However, pregnant participants will be excluded from procedures such as organ tissue collection, stable isotope studies, testing, and brain or cardiac MRI until the pregnancy is concluded.

  • Healthy volunteers may be eligible to participate in the study if they are between 12 - 40 years of age, must meet specific criteria (similar to affected individuals studied).
  • Patients with propionic acidemia over 1 month of age, of any gender and ethnicity, undergoing a transplantation surgery at Children s Hospital of Pittsburgh, are eligible to participate in the tissue collection arm of the study.

Exclusion criteria

EXCLUSION CRITERIA:

  • The PI/AI may decline to enroll a patient because of poor metabolic control, lack of a primary metabolic/genetics physician, and intercurrent infection are exclusion criteria for this protocol, the likelihood that an acutely ill or poorly controlled patient will enroll will be minimized.
  • A subset of participants may be enrolled in the tissue collection part of the study only (i.e. if they are too sick to travel). We can may also arrange limited remote consultation with our research team and NIH consultants, the participants referring physician and the participant/their legal guardian through the telephone or an NIH supported telehealth platform for participants who are unable to safely travel to NIH. This would not replace a study visit but would be used when travel isn t possible due to extenuating circumstances (e.g. pandemic). Participants would be encouraged to follow-up for a more thorough in-person evaluation when they are able to travel to NIH.
  • For the healthy volunteers, they will be excluded if they have halitosis, cavities, dental or gingival problems, respiratory diseases (for example, asthma or recent history of COVID19), use tobacco products (for example, cigarette smoking or chewing tobacco), or use electronic nicotine delivery systems (for example, use of e-cigarettes or vaping devices), as this may interfere with accurate measurement of their volatile organic compounds. NIH staff and their family members will be eligible to participate in the healthy volunteer portion of the study.
Terms in these criteria, in plain language(2)

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.

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.

BMI (body mass index)

Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.

What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.

05

Study design

Observational model
Cohort
Time perspective
Prospective
Enrollment
1,045 participants (estimated)

Groups and cohorts

  • Affected Patients with Propionic Acidemia

    Patients with Propionic Acidemia, standard adult, parental permission

  • Healthy Volunteers

    Healthy Volunteers, standard adult, parental permission

  • Unaffected Family Members

    Unaffected family members

06

What researchers measure

Primary outcomes

  1. Natural history to asess long term complications of Propionic Acidemia

    assessing the long term complications of Propionic Acidemia during a week long evaluation with imaging, labs, and consultations.

    Time frame: Ongoing

07

Study locations

2 of 2 sites recruiting
  • National Institutes of Health Clinical Center
    Bethesda, Maryland 20892, United States
    Recruiting
    • For more information at the NIH Clinical Center contact Office of Patient Recruitment (OPR) · Contactprpl@cc.nih.gov · 800-411-1222
  • Children's Hospital of Pittsburgh
    Pittsburgh, Pennsylvania 15224, United States
    Recruiting
08

References and documents

Publications

  • Shchelochkov OA, Davies H, Mohney RP, Hatch A, Birch O, Ferry S, Van Ryzin C, Hall C, McCoy S, Vockley J, Kuo MJM, Manoli I, Sloan JL, Venditti CP. Breath biopsy in inborn errors of metabolism: A proof-of-principle study in propionic acidemia. Mol Genet Metab. 2025 Mar;144(3):109005. doi: 10.1016/j.ymgme.2024.109005. Epub 2024 Dec 21. PubMed 39787887 ↗
  • Shchelochkov OA, Manoli I, Juneau P, Sloan JL, Ferry S, Myles J, Schoenfeld M, Pass A, McCoy S, Van Ryzin C, Wenger O, Levin M, Zein W, Huryn L, Snow J, Chlebowski C, Thurm A, Kopp JB, Chen KY, Venditti CP. Severity modeling of propionic acidemia using clinical and laboratory biomarkers. Genet Med. 2021 Aug;23(8):1534-1542. doi: 10.1038/s41436-021-01173-2. Epub 2021 May 18. PubMed 34007002 ↗
  • Shchelochkov OA, Manoli I, Sloan JL, Ferry S, Pass A, Van Ryzin C, Myles J, Schoenfeld M, McGuire P, Rosing DR, Levin MD, Kopp JB, Venditti CP. Chronic kidney disease in propionic acidemia. Genet Med. 2019 Dec;21(12):2830-2835. doi: 10.1038/s41436-019-0593-z. Epub 2019 Jun 28. PubMed 31249402 ↗

Individual participant data

Plan to share: No — Study is observational natural history study that is ongoing with no defined endpoints

09

Timeline

6 registry updates since Sep 25, 2026
ElapsedEstimatedEstimated, not yet reached

Started Nov 2016 (actual). Primary completion is estimated for Aug 2036, 237 months after the start.

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

Registered
Sep 3, 2016
First posted
Sep 7, 2016
StartActual
Nov 29, 2016
Primary completionEst.
Aug 31, 2036
CompletionEst.
Aug 31, 2036
Last update
Nov 9, 2026
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.
Minor edits
Nothing that changes what the study is or who can join. Edited: description
6 updates, last Nov 9, 2026
Show all 6 updates
  1. Nov 9, 2026
    Minor edits only
    + 1 other change: description
  2. Nov 5, 2026
    Minor edits only
    + 1 other change: description
  3. Oct 29, 2026
    Minor edits only
    + 1 other change: description
  4. Oct 26, 2026
    Minor edits only
    + 1 other change: description
  5. Oct 16, 2026
    Minor edits only
    + 1 other change: description
  6. Sep 28, 2026
    Minor edits only
    + 1 other change: description

From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗

10

Registry details

Key details

Study ID
NCT02890342
Responsible party
Sponsor
First posted
Sep 7, 2016
Start date
Nov 29, 2016
Primary completion
Aug 31, 2036 (estimated)
Completion
Aug 31, 2036 (estimated)
Last update
Nov 9, 2026

Study contacts

Susan C Ferry, R.N.
Contact
pastudy@mail.nih.gov
(301) 496-6213
Charles P Venditti, M.D.
Contact
venditti@mail.nih.gov
(301) 496-6213
Charles P Venditti, M.D.
principal investigator · National Human Genome Research Institute (NHGRI)

Oversight

FDA-regulated drug
No
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

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