ClinicalTrials.gov record NCT05848271

Natural History Study of Patients with HPDL Mutations

Record copied from ClinicalTrials.gov: Oct 10, 2026AI summaries generated: Jul 27, 2026

A Patient Registry and Natural History Study of Patients with Biallelic HPDL Mutations

StatusRecruitingThe study is currently enrolling participants. Only the study team can say whether a particular person can join.
Study typeObservationalA study in which researchers do not assign participants to a treatment or other intervention. They observe or measure what happens, which may include study visits, tests, questionnaires or a review of medical records.
SexAll
LocationUnited States
AI summaryWhat this study is about, in plain languageShow ▾Hide ▴

AI-written from the registry record, not the study's own wording. May contain errors or omissions. Check the registry text on this page and the original record ↗ before acting on it.

This observational study creates a patient registry of people with HPDL gene variants. It uses past medical records and clinician questionnaires and collects dry blood spots. The study aims to describe how HPDL-related conditions change over time and to explore genotype–phenotype links and biomarkers.

What it is studying. The study is gathering and analyzing clinical records, clinician-reported information, and dry blood spot samples to define the natural history of HPDL-related disorders, study genotype–phenotype correlations, and develop biomarkers.

What the researchers hope to learn. To build a patient registry of people with HPDL mutations; to describe the clinical course (natural history) of HPDL-related conditions; to investigate connections between specific HPDL variants and clinical features; and to develop biomarkers using dry blood spot samples.

What this study is about

The study's own summary, as published on ClinicalTrials.gov. Underlined terms have a short explanation.

This study uses medical records that allow retrospective data extraction of clinical manifestation to assess the natural history of HPDL mutations

Interventions being studied

Being studied in this trial does not mean the treatment or procedure is approved or available for this condition.

Other
  • Patient Registry
  • Dry blood spots sampling

Eligibility

The criteria exactly as listed on ClinicalTrials.gov. Only the study team can say whether they apply to you.

Inclusion criteria

  • Any individuals diagnosed with HPDL variants
  • Clinical diagnosis can include:
  • HPDL-related hereditary spastic paraplegia (HSP)
  • HPDL-related neonatal mitochondrial encephalopathy
  • Spastic paraplegia -83 (SPG83)
  • Neurodevelopmental disorder with progressive spasticity and brain white matter abnormalities (NEDSWMA)

Exclusion criteria

  • Any known genetic abnormality (other than HPDL mutation)
  • Any condition that, in the opinion of the Site Investigator, could put the participant at undue risk and/or would ultimately prevent the completion of study procedures

Study description and what participation involves

The study's detailed description, as published on ClinicalTrials.gov.

Detailed description from the registry

A novel mitochondrial disease arises from mutations in HPDL, which codes for 4-hydroxyphenylpyruvate dioxygenase-like protein. The main purpose of this study is to establish a patient registry to gather medical data from consenting HPDL mutation patients worldwide. From longitudinal data, we will be able to figure out the natural history of the disease, and genotype-phenotype correlation. Dry blood spots will be collected to develop biomarkers to understand the disease better.

AI summaryWhat participation may involve, in plain languageShow ▾Hide ▴

AI-written from the registry record, not the study's own wording. May contain errors or omissions. Check the registry text on this page and the original record ↗ before acting on it.

If you join, the study team will collect medical record information for retrospective data extraction and ask your clinician to complete a questionnaire to confirm clinical and genetic details (the registry lists this clinician questionnaire with a 12‑month time frame). The study also involves submitting a dry blood spot sample (the record specifies 500 nL of blood). These are the procedures described in the registry; no other participant services or procedures are specified.

How the study is structured. A retrospective observational cohort registry: participants with HPDL variants are enrolled into a registry; researchers extract past clinical data from medical records, collect a dry blood spot sample (record states 500nl of blood), and obtain clinician questionnaires (primary outcome measured at 12 months).

Questions you could ask

These questions are suggestions for a conversation with the study team or your own clinician, not advice.

  • This is an observational study, so the study itself gives no treatment. What would taking part involve for me, and would it change my usual care?
  • The listed sites are in United States. Is any of them reachable for me, and does the study help with travel?
  • Which of the eligibility criteria would need to be checked with tests before I could join?

More on hereditary spastic paraplegia

Clinical trials21 trials listed for hereditary spastic paraplegiaEvery trial the registry lists for hereditary spastic paraplegia, with recruitment status, phase and sites, updated from ClinicalTrials.gov.See all trials →Research updatesWhat changed in hereditary spastic paraplegia researchLatest monthly update: September 2026. Includes: SPTSSA treatment signal. New research summarized each month in plain language, with links to every source paper.Read the latest update →

Important dates

Study start
May 18, 2023
Primary completion
Dec 31, 2026 (estimated)
Study completion
Dec 31, 2027 (estimated)
Target enrollment
50 participants (estimated)
Last updated on registry
Mar 30, 2025
Data verified
Oct 10, 2026

Sponsor and research team

The lead sponsor funds and oversees the trial. A pharmaceutical or biotech company sponsor typically means the study is testing that company's drug or device; a hospital, university, or government agency usually indicates investigator-initiated or publicly funded research.

Lead sponsor
University of California, San Diego
Principal investigator
Joseph Gleeson, professor, neuroscience
University of California, San Diego
Collaborators
  • New York University
  • Universität Tübingen
  • Heinrich-Heine University, Duesseldorf

Central study contact

If you're interested in participating, the central contact can answer general questions about the study — including eligibility requirements and how to find a recruiting site near you. Actual eligibility is determined by the site's medical team.

Participating sites (1)

Terms used on this page · explanations by MedicalUpdates.ai

natural history
A study that follows how a condition changes over time without assigning an experimental treatment. It may involve study visits and tests, and is often used to plan future trials.
Inclusion Criteria
The conditions a person must meet to be considered for the study, for example a confirmed diagnosis, an age range or a test result.
Exclusion Criteria
The conditions that rule a person out even if they meet the inclusion criteria, for example other illnesses, certain medicines or pregnancy.
patient registry
An organised collection of information about people with a particular condition, gathered over time for research. Joining a registry usually means sharing medical information, not receiving a treatment.
biomarkers
Something measurable in the body, such as a blood test result or an imaging finding, that indicates how a condition or treatment is behaving.

The study record on this page is reproduced from ClinicalTrials.gov, a database of the U.S. National Library of Medicine, where it was submitted by the study sponsor. MedicalUpdates.ai does not own this content, is not affiliated with or endorsed by ClinicalTrials.gov, NIH, or the U.S. Government, and does not verify the record. Plain-language notes, the glossary and the questions above are added by this site; text in the boxes marked "AI summary" was written by an AI model and may contain errors. Registry records change over time. Check the original record for the current version and discuss eligibility or participation with a qualified healthcare professional.

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