ClinicalTrials.gov record NCT06683365

Autologous suraL nervE Grafting to the Substantia nigrA in Patients With Synuclienopathies

Record copied from ClinicalTrials.gov: Oct 10, 2026AI summaries generated: Sep 7, 2026

A Phase I Study of the Feasibility and Safety of SuraL nervE Tissue Grafting to the Substantia nigrA in Patients With Synucleinopathies (LEAP)

StatusRecruitingThe study is currently enrolling participants. Only the study team can say whether a particular person can join.
Study typeInterventionalA study in which researchers assign participants to one or more interventions, such as a drug, procedure, device, behavioural programme or other approach, to measure their effects.
PhasePhase 1An early-stage study, usually small, mainly to check safety, side effects and how much of a treatment can be given. Whether it works is not the main question yet.
Age40 years old to 75 years old
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 Phase I trial tests whether implanting autologous sural (leg) nerve tissue into the brain's substantia nigra is feasible and safe in people with Parkinson's disease or Multiple System Atrophy. The study will enroll seven participants: four will receive the graft procedure and three will receive a sham surgery. Participants are followed for about 12 months after surgery.

What it is studying. The study is measuring feasibility and safety of taking a small piece of a person's sural nerve and placing that tissue into both sides of the substantia nigra (a brain area affected in PD and MSA). It will record surgical outcomes and adverse events, and collect clinical and neuropsychological measures over one year to inform future, larger trials.

What the researchers hope to learn. To determine whether harvesting and implanting a person's own peripheral nerve tissue into the substantia nigra is practical and safe, and to collect clinical and cognitive data that could guide design of larger future trials.

What this study is about

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

This phase I double-blind study focuses on the safety and feasibility of implanting autologous peripheral nerve tissue (PNT) into the substantia nigra area of the brain in persons who have been diagnosed with either Parkinson's disease (PD) or Multiple System Atrophy (MSA). 7 participants will be enrolled, with 4 participants receiving the graft and 3 receiving a sham surgery. Eligible participants will be early in their diagnosis with a lower burden of symptoms. Participants will be followed initially for one year after surgery.

Interventions being studied

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

Procedure
  • Sural Nerve Graft to the Substantia Nigra
  • Sham surgery

Eligibility

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

Inclusion criteria

  • Diagnosis of clinically established or clinically probable PD or MSA as defined by MDS criteria
  • Disease duration greater than 2 years
  • Age 40-75, inclusive
  • MDS-Unified Parkinson's Disease Rating Scale (UPDRS) Part III greater than or equal to 20 points but less than or equal to 35 points, off anti-parkinsonian medication for PD or MDS-Unified Multiple System Atrophy Rating Scale (UMSARS) less than or equal to 30 points off anti-parkinsonian medication
  • No MDS-UPDRS Part III score >3 on items 3.3, 3.4, 3.5, 3.6, 3.7, 3.8, 3.14 while off medication
  • Able and willing to undergo ioflupane/SPECT
  • Able to tolerate the surgical procedure
  • Able to undergo all planned assessments
  • Available access to the sural nerve

Exclusion criteria

  • Previous PD surgery or intracranial surgery
  • Ongoing major medical or psychiatric disorder incl. depression and psychosis
  • Other concomitant treatment with neuroleptics
  • Typical, nonparkinsonian syndrome ioflupane/SPECT signal
  • Unable to undergo an MRI
  • An obstructed trajectory path to the substantia nigra
  • Significant microvascular disease
  • Use of anticoagulants other than aspirin
  • Female who is pregnant, lactating, or of child-bearing potential unwilling to use an adequate birth control method during the period of the study
  • Consent capacity will be assessed and determined during and throughout a participant's neuropsychological exam. A participant who experiences a decline in consent capacity prior to surgery, will be removed from the study by the PI. A decline in consent capacity after surgery will not result in the removal of the participant in the study.

Study description and what participation involves

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

Detailed description from the registry

This phase I double blind clinical trial will be used to plan future, larger clinical trials that would test how autologous cells from the peripheral nerve may help in the repair of damaged brain cells in Parkinson's Disease (PD) or Multiple System Atrophy (MSA) and slow the progression of the diseases. We will be judging the feasibility of implanting a participant's own cells from a nerve in the leg into the substantia nigra area of the brain. Patients eligible for participation will be at an earlier in stage of the disease with symptoms being less severe and therefore would not yet qualify for DBS. The LEAP trial is a study where the first participant will receive an implantation of the cells from their own sural nerve (a nerve near the ankle), into the substantia nigra on both sides of their brain. The 6 participants who follow, will be randomized to one of two arms. The 3 participants assigned to the experimental arm will receive the graft. The 3 participants assigned to the control arm will receive a sham surgical procedure, where the sural nerve will be biopsied, and bilateral scalp incisions will be made. Those who do not receive the cells initially may be eligible to undergo another surgery at the end of the study, after un-blinding has occurred, to receive the cell implants.

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.

You would have a sural nerve biopsy from one ankle. Participants are randomized: some receive the nerve tissue implanted bilaterally into the substantia nigra through scalp incisions and skull burr holes; others receive a sham surgery with scalp incisions but no brain implant (both arms include the ankle biopsy). The procedure requires anesthesia and a hospital admission (the study records how many days you stay), and you will have follow-up visits through about 12 months with brain imaging (ioflupane/SPECT), cognitive testing, Parkinson/MSA rating scales, questionnaires, and other planned assessments. If you are in the sham group, you may be eligible for a second surgery to receive the cell implants after the study is unblinded.

How the study is structured. Phase I interventional surgical trial. After the first participant receives the nerve-graft procedure, the next six are randomized into two parallel groups (graft versus sham). Masking is quadruple (blinded). Procedures include a sural nerve biopsy for all participants; the experimental group receives bilateral brain implantation through skull burr holes, while the control group receives scalp incisions only (no burr holes or brain implantation). Follow-up visits and assessments occur through 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 early-phase study, mainly about safety and dose. What is already known about this treatment?
  • 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 multiple system atrophy

Clinical trials76 trials listed for multiple system atrophyEvery trial the registry lists for multiple system atrophy, with recruitment status, phase and sites, updated from ClinicalTrials.gov.See all trials →Research updatesWhat changed in multiple system atrophy researchLatest monthly update: September 2026. Includes: Tube feeding. New research summarized each month in plain language, with links to every source paper.Read the latest update →

Important dates

Study start
Feb 25, 2025
Primary completion
Dec 2, 2028 (estimated)
Study completion
Dec 2, 2030 (estimated)
Target enrollment
7 participants (estimated)
Last updated on registry
Aug 31, 2026
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
Craig van Horne, MD, PhD
Collaborators
  • University of Kentucky CCTS
  • National Center for Advancing Translational Sciences (NCATS)

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

double-blind
Two types of people involved in the study do not know which intervention a participant is receiving. The ClinicalTrials.gov record specifies who is masked, for example participants, care providers, investigators or outcome assessors.
sham
A procedure designed to resemble the real procedure, for example the same visit and equipment, without its active part. It is the procedure equivalent of a placebo.
concomitant treatment
Other medicines a participant takes during the study. Some must be reported; some are restricted.
MRI
A scan that uses magnets and radio waves, not X-rays, to make detailed pictures of the inside of the body. Some implants and metal objects mean a person cannot have one.
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.
randomized
Participants are assigned to the study groups by chance, like a coin toss, rather than chosen by the doctor or the participant. This is done so the groups are comparable.
experimental arm
One of the groups in a study. Each arm receives a particular intervention, comparator or no intervention, so the groups can be compared.
control arm
The group the study treatment is compared with. It may receive a placebo, an existing treatment (active comparator), a sham procedure, or no intervention.
blinding
Who does not know which intervention a participant is receiving. It can apply to participants, the people giving the treatment, those assessing results, or those analysing the data.

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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