RQ-00000010 for Gastroparesis and Constipation in Parkinson's Disease

Inclusion Criteria: For both the Single Ascending Dose and Multiple Ascending Dose studies: Idiopathic Parkinson's Disease (UK Brain Bank Criteria), Hoehn \& Yahr stages 1-3, participants may be on oral levodopa, dopamine agonists, monoamine oxidase-B inhibitors, catechol-O-methyltransferase inhibitors, and amantadine, but doses must have remained stable for 28 days prior to enrollment and should be anticipated to remain stable throughout the study, participants may have deep brain stimulation (though stimulator settings must be expected to remain constant throughout the study) or ablative surgery for Parkinson's Disease. Additional Inclusion criteria for the Multiple Ascending Dose study only: Must have symptoms suggestive of current gastroparesis or constipation as shown by any one or more of the following: 1. Need for regular use of prokinetics, laxatives, or stool softeners of any kind, 2. A total score of 2 or higher on the Gastroparesis Cardinal Symptoms Index (total score equals average of scores on the 3 subscales), 3. A score of 5 or higher on the gastroparesis subscale or 5 or higher on the constipation subscale of the Gastrointestinal Symptoms in Neurodegenerative Disease Scale. \- Exclusion Criteria: Dementia (Mini Mental Status Exam \< 25), active psychosis, severe depression (score of 4 on question 1.3 of the Movement Disorder Society-United Parkinson Disease Rating Scale), active suicidality as measured by a most severe suicide ideation score of 4 or 5 on the Columbia-Suicide Severity Rating Scale (C-SSRS), or patients who answer "Yes" on any of the 5 C-SSRS Suicidal Behavior Items if the attempt or acts were performed within 1 year of screening, or patients who, in the opinion of the investigator, present a risk of suicide, any chronic gastrointestinal diseases except gastroesophageal reflux disease, history of any gastrointestinal surgery that might impact drug absorption (e.g. gastrectomy), use of apomorphine, anticholinergics, or carbidopa/levodopa intestinal gel for Parkinson's Disease, female participants who are pregnant or lactating, male or female participants of childbearing age who are not willing, or whose partners are not willing, to use contraception during the study, diabetes, symptomatic anemia, abnormal liver or kidney function, cardiac arrhythmia (past or present) or abnormal QT interval on entrance electrocardiogram, positive drug screen at screening visit, allergy to spirulina, egg, milk, or wheat, pulmonary dysfunction (e.g. Chronic Obstructive Pulmonary Disease), small bowel malabsorption, use of any medications affecting gastric emptying (macrolides, metoclopramide, domperidone, opiates, anticholinergics) within 3 days of visits 2 and 3, prisoners, and individuals with limited English proficiency. \-