A Phase 1 interventional study of Sural Nerve Graft to the Substantia Nigra and Sham surgery in Multiple System Atrophy and Parkinsons Disease, sponsored by Craig van Horne, MD, PhD. Recruiting at 1 site in United States. Open to participants aged 40 Years to 75 Years. Per ClinicalTrials.gov, last updated 2026-08-31.
Sponsored by Craig van Horne, MD, PhD · Phase 1, Interventional, and Treatment
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.
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.
Exclusion Criteria:
Procedure: Sural Nerve Graft to the Substantia Nigra
Procedure: Sham surgery
Participants assigned to this arm will have the sural nerve biopsied from one of their ankles. This cellular tissue will be deposited bilaterally into the substantia nigra area of their brain by a specialized cannula via bilateral scalp incisions and skull burr holes.
Participants assigned to this arm will have the sural nerve from one of their ankles biopsied in the same fashion as the experimental arm. Bilateral incisions will be made on the participants scalp but no burr holes into the skull and no cannula passes into the brain will occur.
Meet recruitment goal
Ability to recruit, enroll, and assign participants to the trial within 12 months of the trial opening.
Time frame: Trial opening through 12 months
Study-related serious adverse events as assessed by MedDRA v.27
Total number of serious adverse events associated with bilateral PNT collection and deployment to the substantia nigra. Serious adverse events will be defined as an abscess, tumor, infection of the bed of the graft, altered mental state, seizure, ankle or foot infection, wound dehiscence at the ankle incision, spread of neuropathy of the ankle or foot on the ipsilateral side of the nerve biopsy, or other event determined by the PI/investigators to be important.
Time frame: Enrollment through 12 months
Study-related adverse events as assessed by MedDRA v27
Total number of adverse events experienced by participants categorized by System Organ Class and/or High Level Group Term using MedDRA v27 for designation.
Time frame: Enrollment through 6 month study visit
Number of deployment attempts required to deliver bilateral PNT
Per protocol, the surgeon has two chances to successfully deploy 60% of the PNT tissue loaded in the guide-tube into the brain per hemisphere. The number of attempted deployments will be documented and if \<60% of the tissue is deployed after two attempts, a failed delivery will be documented and no other attempts will be made.
Time frame: During the procedure
Duration of procedure
Number of minutes it takes for the procedure to be completed. This will be defined by the anesthesia start time and anesthesia end time.
Time frame: During the procedure
Length of hospital admission
The number of days each participant is admitted to the inpatient hospital for the procedure and acute post-operative care.
Time frame: Admission for the procedure through hospital discharge
Percent of study visit completed by participants
The number of designated study visits completed compared to the total number of study visits that are scheduled to occur.
Time frame: Enrollement through 12 month study visit
Change in Neuropsychological diagnosis
Changes in participant neuropsychological diagnoses during scheduled evaluations will be reported. e.g. No cognitive diagnosis progressing to mild neurocognitive disorder.
Time frame: Baseline and 12 months
Mean change in Neuropsychological assessment scores
Participants complete a neuropsychological assessment battery that meets the MDS guidelines for determining mild cognitive impairment/mild neurocognitive disorder. Domains include attention and working memory, executive functioning, memory (verbal and visual), language, and visuospatial skills. Participants' raw scores will be converted to standardized scores based on appropriate norms (e.g., age-based norms). Participants' 12 month re-evaluation will be compared to their baseline pre-surgical assessment to determine change from baseline on each measure. A change that exceeds 1.5 standard deviation from their baseline performance will be considered notable.
Time frame: Baseline to 12 months
Mean change in Montreal Cognitive Assessment (MoCA) scores
Mean change in MoCA scores for participants at study visits compared to baseline by group allocation. Assessment is scored from 0-30 with a score of 26 or better indicating normal cognition. A score less than 26 indicates a cognitive deficit.
Time frame: Baseline, 4 weeks, 6 months, and 12 months
Mean change of the Movement Disorder Society - Unified Parkinsons Disease Rating Scale (MDS-UPDRS) Part I scores
MDS-UPDRS Part I scores non-motor symptoms effecting activities of daily living in those with Parkinson's Disease. Scores range from 0-52 with higher scores indicating greater symptom severity.
Time frame: 4 weeks, 6 and 12 months as compared to baseline
Mean change of the MDS-UPDRS Part II scores
MDS-UPDRS Part II scores motor symptoms effecting activities of daily living in those with Parkinson's Disease. Scores range from 0-52 with higher scores indicating greater symptom severity.
Time frame: 4 weeks, 6 months, and 12 months compared to baseline
Mean change in MDS-UPDRS Part III scores
MDS-UPDRS Part III scores motor symptoms associated with Parkinson's Disease. Part III scores range from 0-132 with higher scores indicating higher symptom severity.
Time frame: 4 weeks, 6 and 12 months compared to baseline
Mean change in MDS-UPDRS Part IV scores
MDS-UPDRS Part IV scores motor complications such as fluctuations and dyskinesia's associated with anti-Parkinson's medications. Scores range from 0-24 with higher scores indicating greater severity in motor complications.
Time frame: 4 weeks, 6 and 12 months compared to baseline
Mean change of the Movement Disorder Society - Unified Multiple System Atrophy Rating Scale (MDS-UMSARS) Part I scores
MDS-UMSARS Part I rates patient reported functional disabilities. Scores for this section range from 0-48 with higher scores indicating greater disability
Time frame: 4 weeks, 6 and 12 months as compared to baseline
Mean change of the MDS-UMSARS Part II scores
MDS-UMSARS Part II scores motor symptoms associated with multiple system atrophy. Scores range from 0-56 with higher scores indicating greater symptom severity.
Time frame: 4 weeks, 6 months, and 12 months compared to baseline
Mean change in MDS-UMSARS Part III scores
MDS-UMSARS Part III assesses orthostatic hypertension symptoms. This part examines blood pressure changes when a participant stands up after laying down for two minutes. It is scored as either a "Yes" the participant experiences orthostatic hypertension, or a "No" the participant does not don't experience orthostatic hypertension.
Time frame: 4 weeks, 6 and 12 months compared to baseline
Mean change in MDS-UMSARS Part IV scores
MDS-UMSARS Part IV assess the participants global disability. Scores range from 1-5 with 1 being completely independent and 5 being totally dependent/bedridden.
Time frame: 4 weeks, 6 and 12 months compared to baseline
Mean change in Parkinson's Disease Questionnaire-8 (PDQ-8) quality of life scores
Assess changes in participant's quality of life. Questionnaire is scored from 0-32 with higher scores indicating poorer quality of life.
Time frame: Monthly through 12 month study visit compared to baseline
Mean change in Modified Schwab and England Scale of Activities of Daily Living scores
Mean change participant independence levels as measured in Schwab and England Scale of Activities of Daily Living scores. 100% = completed independent and 0% being completely dependent.
Time frame: At 6 and 12 months compared to baseline
Mean change in Non-motor symptom scale scores
Assessment used to identify Parkinson's disease related non-motor symptoms experienced by participants. The scale measures the frequency and severity of symptoms and is scored from 0-360 with higher scores indicating more frequent and severe symptoms.
Time frame: Baseline and 12 months
Participants electing to receive Deep Brain Stimulator (DBS)
Number of study participants who elect to have DBS implanted prior to completing the 12 month study visit.
Time frame: Enrollment through 12 month study visit
Plan to share: Yes — Images and results may be made available to other researchers by asking participants, at the time of consent, their willingness to permit sharing of data and bio-specimens.
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Craig van Horne, MD, PhD