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OpenTrials
Completed

NCT Number: NCT06263010

Allopregnanolone as a Regenerative Treatment for Parkinson's Disease

The goal of this open-label, pilot clinical trial is to test allopregnanolone as a regenerative treatment in patients with Parkinson's disease (PD). The main questions this study aims to answer are:

1. Is a large-scale clinical trial testing how well it works in patients with PD feasible? 2. Is allopregnanolone safe and well-tolerated in patients with PD. 3. Can we see any signals of changes in imaging and clinical scales?

Participants will receive a weekly infusion in their vein of allopregnanolone for a total of 12 weeks. There is no placebo so everyone receives allopregnanolone and "Open-label" means the study is not blinded so both the participant and investigators know the assigned treatment.

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Key information

Conditions

Parkinson Disease Basal Ganglia Diseases Brain Diseases Central Nervous System Diseases Movement Disorders Nervous System Diseases Neurodegenerative Diseases Parkinsonian Disorders Synucleinopathies

Age range

40 year–85 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Phase 1

Primary location

The University of Arizona Clinical & Translational Science Research Center

Tucson, Arizona, 85721, United States

About this study

This is an open-label, pilot clinical trial of allopregnanolone (Allo) as a regenerative treatment for Parkinson's disease. A total of 10 study participants will receive weekly infusions of Allo for 12 weeks. Participants will be male and female, age 40-80 years with a history of idiopathic, sporadic PD who have a Hoehn & Yahr stage 1-4. Allo is a potent neuroregenerative agent that promotes proliferation of human neural stem cells and has the potential to function as a regenerative therapeutic to restore motor function in persons with PD. Results from several preclinical studies in rodent models of PD confirm improved motor function after Allo treatment.

Primary Objective: To assess the feasibility of a large-scale trial to determine the efficacy of weekly infusions of Allo in in patients with Idiopathic sporadic PD.

Secondary Objectives: To evaluate the safety and tolerability of weekly infusions of Allo in participants with idiopathic sporadic PD, and assess single-dose pharmacokinetics of allopregnanolone.

Tertiary / Exploratory Objectives: To assess efficacy signals of weekly infusions of Allo in participants with idiopathic sporadic PD.

  • Determine target engagement of Allo using dopamine transporter (DaT) imaging and magnetic resonance imaging (MRI).
  • Evaluate effect of Allo on motor function tests.
  • Evaluate the effect of Allo on cognitive function tests and clinical ratings.
  • Compare response to Allo administration between APOE4 carriers and non-carriers.

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • History of Idiopathic sporadic Parkinson disease
  • Hoehn & Yahr stage 1-4
  • Have been on stable doses of all anti-Parkinson's medications for 30 days prior to screening
  • Provision of signed and dated informed consent form

Exclusion criteria

  • Evidence of Parkinsonian syndrome.
  • Any conditions that would contraindicate MRI studies.
  • Undergone deep brain stimulation (DBS) surgery as treatment for PD.
  • Iodine allergy, known serious hypersensitivity to ioflupane I-123, or other inability to undergo DaTscan.
  • Clinically significant abnormal laboratory value and/or clinically significant unstable medical or psychiatric illness.
  • History within the last 5 years of a primary or recurrent malignant disease, with the exception of resected cutaneous squamous cell carcinoma in situ, basal cell carcinoma, cervical carcinoma in situ, or prostate cancer in situ with a post-treatment prostatic-specific antigen within normal range.
  • Serious or unstable illnesses including cardiovascular, hepatic, renal, gastroenterologic, respiratory, endocrinologic, neurologic (other than PD), psychiatric, immunologic, or hematologic disease, and any other conditions that, in the investigator's opinion, could interfere with the safety and efficacy analyses in this study.
  • History of chronic alcohol or substance abuse/dependence within the past 3 years.
  • Current use of benzodiazepines, anticonvulsants, antipsychotics, or other drugs that might interact with the gamma-aminobutyric acid-A (GABA-A) receptor complex; use of calcium-channel blockers (e.g., amlodipine); use of dietary supplements containing Pregnenolone.
  • Treatment with another investigational drug within 3 months of screening.

Treatment and study plan

Allopregnanolone

Drug

Allopregnanolone is a neurosteroid ( 3α,5α-tetrahydroprogesterone, 3α-hydroxy-5α-pregnan-20-one) and by-product of the metabolism of the hormone progesterone.

Primary outcomes

  1. Study completion

    Time frame: Week 13

    Proportion of participant progression to study completion.

Secondary outcomes

  1. Adverse Events

    Time frame: Weekly from Baseline to Week 16

    Proportion of participants with adverse events to assess safety.

  2. Infusion Reactions

    Time frame: Weekly from Week 1 to Week 16

    Proportion of participants with infusion reactions to assess tolerability.

  3. Pharmacokinetics: Peak Plasma Concentration (Cmax)

    Time frame: Week 1

    The highest concentration in plasma of allopregnanolone after an IV dose.

  4. Pharmacokinetics: Time of peak concentration (tmax)

    Time frame: Week 1

    Time required to achieve peak plasma levels

  5. Pharmacokinetics: Half-life (t1/2)

    Time frame: Week 1

    The time required for plasma concentration of Allopregnanolone to decrease by 50%.

  6. Pharmacokinetics: Area under the plasma concentration versus time curve (AUC)

    Time frame: Week 1

    The concentration of phytoSERMs in blood plasma as a function of time. Gives insight into the extent of exposure to phytoSERM and its clearance rate from the body.

Other outcomes

  1. Dopamine transporter (DaT) SPECT imaging

    Time frame: Baseline to week 13

    Change from baseline in DaT imaging z-scores.

  2. MRI: Regional brain volumes

    Time frame: Screening to week 13

    T1-weighted volumetric MRI (mm3).

  3. MRI: Fractional Anisotropy

    Time frame: Screening to week 13

    Multi-band multi-shell Diffusion Tensor Imaging (DTI) to measure changes in white matter tract integrity.

  4. MRI: Quantitative anisotropy

    Time frame: Screening to week 13

    DTI to measure changes in white matter tract integrity. The amount of anisotropic spins that diffuse along the fiber orientation.

  5. MRI: Functional connectivity

    Time frame: Screening to week 13

    Resting state functional MRI (rs-fMRI) to measure changes in intrinsic connectivity, which also correlates to neuronal function.

  6. Mean rate of change in the Movement Disorder Society Unified Parkinson's Disease Rating Scale (MDS-UPDRS) score part I (non-motor EDL)

    Time frame: Baseline to week 13

    MDS-UPDRS part I will evaluate non-motor Experiences of Daily Living (cognition, behavior, mood, etc.).

  7. Mean rate of change in the Movement Disorder Society Unified Parkinson's Disease Rating Scale (MDS-UPDRS) score part II (motor EDL)

    Time frame: Baseline to week 13

    MDS-UPDRS part II will evaluate motor Experiences of Daily Living (speech, eating, grooming, walking, etc.).

    The UPDRS Part II consists of 13 items scored between 0 and 4. The sum score ranges from 0 to 52, higher scores denote greater disability.

  8. Mean rate of change in the Movement Disorder Society Unified Parkinson's Disease Rating Scale (MDS-UPDRS) score part III (motor examination)

    Time frame: Baseline to week 13

    MDS-UPDRS part III (motor subscale) assesses the motor signs of PD. It consists of 27 items and sub items scored between 0 and 4. The sum score ranges from 0 to 108, higher scores denote greater disability.

  9. Mean rate of change in the Movement Disorder Society Unified Parkinson's Disease Rating Scale (MDS-UPDRS) score part IV (motor complications)

    Time frame: Baseline to week 13

    MDS-UPDRS part IV of the scale assesses two motor complications, dyskinesias and motor fluctuations that include OFF-state dystonia.

    Score ranges from 0-44, higher scores denote greater disability. The UPDRS Part III (motor subscale) consists of 27 items and sub items scored between 0 and 4. The sum score ranges from 0 to 108, higher scores denote greater disability.

  10. Mean rate of change in the Unified Dyskinesia Rating Scale (UDysRS) total score

    Time frame: Baseline to week 13

    Scale designed to capture the essential features of dyskinesia in PD. Score range is 0-104, higher scores denote greater disability.

  11. Change from baseline in Montreal Cognitive Assessment (MoCA) score

    Time frame: Baseline to week 13

    Test used to detect cognitive impairment, measuring executive functions and multiple cognitive domains. Score ranges from 0-30, with higher scores denoting better performance.

  12. Change from baseline in Parkinson's disease Questionnaire (PDQ-39).

    Time frame: Baseline to week 13

    PD specific health status questionnaire comprising 39 items. Items are grouped into eight scales that are scored by expressing summed item scores as a percentage score ranging between 0 and 100.

  13. Change from baseline in Hamilton Depression Rating Scale (HAM-D)

    Time frame: Baseline to week 13

    Scale used to measure depression severity. Score ranges from 0-52, with higher scores indicating worst outcome.

  14. Cambridge Cognition's Paired Associates Learning (PAL) Test

    Time frame: Baseline to week 13

    Total errors score (adjusted) - number of errors made by the participant (range: 0 to ~120). Higher scores indicate poor performance.

  15. Cambridge Cognition's Motor Screening Task (MOT)

    Time frame: Baseline to week 13

    Outcome measures cover accuracy and difficulty speed adjustment. The mean latency for a subject to correctly respond to the stimulus on screen during assessed trials, measured in milliseconds. Range from 0 to 6000ms.

  16. Cambridge Cognition's One Touch Stockings of Cambridge (OTS)

    Time frame: Baseline to week 13

    It assesses both the spatial planning and the working memory subdomains. Outcome measure is the total number of assessed trials where the subject chose the correct answer on their first attempt. Range 0 to 15.

Sponsors and collaborators

Lead sponsor

Roberta Brinton

Other

Registry information

Official study title

Allopregnanolone as a Regenerative Treatment for Parkinson's Disease: An Open-label, Pilot Clinical Trial

Acronym: Allo-PD

Important dates

Study start
2024
Primary completion
2025
Study completion
2025
First posted
Feb 16, 2024
Registry last updated
Mar 13, 2026

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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