A Phase III Double Blind, Placebo-Controlled, parallel group study of Isradipine as a disease modifying agent in subjects with early Parkinson disease.
The following medications are restricted or not allowed during subject participation in the study
If any disallowed medications are required and cannot be discontinued, study drug should be stopped and the subject should continue to be followed in the study off of study drug. Please notify the study team immediately regarding initiation of disallowed medications. Once a disallowed medication is stopped, the subject may be restarted on study treatment per the re-titration rules.
Subjects with a history of hypertension treated with no more than 2 other antihypertensive agents (except for calcium channel blockers) will be allowed provided that the dosages of concomitant antihypertensive therapy can be reduced/adjusted during the study based on the BP readings in consultation with the Primary Care Provider and/or cardiologist of the participant. As needed, a UR cardiologist will be available for consultation. Drugs with antihypertensive properties but being used for indications other than hypertension will be allowed.
Dihydropyridine Calcium channel blockers:
The use of Dihydropyridine Calcium channel blockers are not allowed for 6 months prior to baseline and during the study.
Non-Dihydropyridine Calcium Channel Blockers
Non-Dihydropyridine Calcium Channel Blockers are prohibited from screening visit onward and for the duration of study:
Fentanyl Anesthesia use has been associated with hypotension with concomitant use of calcium channel blockers and should be avoided if possible.
Drug Interactions with Isradipine:
Throughout the entirety of the study, grapefruit juice, ginkgo biloba, ginseng, are prohibited because they increase isradipine serum blood levels. Also, St. John’s wort is prohibited because it decreases isradipine serum blood levels. CYP 3A4 inhibitors/inducers affect the metabolism of isradipine and should be monitored for potential adverse events related to an increase or decrease in isradipine serum blood levels.
Clarithromycin, erythromycin and telithromycin antibiotics are prohibited starting from the screening visit and for the duration of the study. There is an associated increased risk of heart and kidney injury. If antibiotic treatment is required, use of antibiotics other than clarithromycin or erythromycin treatment is required. Study drug should be stopped through the duration of treatment and restarted after treatment per re-titration rules.
The use of antipsychotics or other dopamine blocking agents within 6 months before baseline visit and for the duration of the study is prohibited. Note: atypical neuroleptics, clozeapine and quetiapine will be allowed at the discretion of the Investigator.
Antidepressant Medications or Central Nervous System (CNS) acting medications:
A stable regimen of central nervous system acting medications (benzodiazepines, antidepressants, hypnotics) is allowed. The dosage has to be stable for 30 days prior to the baseline visit. The dosage can be adjusted during the study at the discretion of the Investigator. Central nervous system acting medications can be initiated during the study, if needed, at the discretion of the Investigator.