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:

Is a large-scale clinical trial testing how well it works in patients with PD feasible?
Is allopregnanolone safe and well-tolerated in patients with PD.
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.
- EligibilityCriteria: 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. - HealthyVolunteers: No - Gender: All - MinimumAge: 40 Years - MaximumAge: 85 Years - StdAgeList: Adult, Older Adult