After proving safe in a study funded by The Michael J. Fox Foundation (MJFF), the compound isradipine is moving to Phase III testing of its effect on Parkinson’s disease (PD) thanks to a $23 million grant from the National Institutes of Health (NIH).
When recruitment begins later this year, this trial will be the most advanced, current study into a disease-modifying therapy for Parkinson’s.
Isradipine is a calcium channel blocker currently prescribed to treat high blood pressure. Data from large studies note a lower incidence of PD among people who take this drug.
“In these epidemiological studies there was approximately 30 percent less risk of developing Parkinson’s in the subgroup of patients treated with this class of drugs for blood pressure,” said Tanya Simuni, MD, director of the Parkinson’s Disease and Movement Disorders Program at Northwestern University and principal investigator of this study.
The NIH funding will move the Safety, Tolerability and Efficacy Assessment of Dynacirc® for PD (STEADY-PD) study into Phase III efficacy testing. Dynacirc® is the commercial name of the isradipine hypertension drug. Simuni and the Parkinson Study Group hope to enroll more than 300 participants at 56 clinical sites throughout North America.
MJFF began funding isradipine research in 2007 with support for a project from D. James Surmeier, PhD, also of Northwestern University, looking at the compound’s neuroprotective effects in PD models. The NIH also funded Surmeier’s pre-clinical work into this compound.
In 2008, the Foundation granted STEADY-PD $2.1 million for the Phase II clinical trial, and researchers published results in September 2013 in the Movement Disorders journal showing that isradipine is safe and tolerable in PD patients. They also determined the maximal, tolerable dosage (10 mg daily).
Drug repurposing — studying a small molecule or compound approved to treat one disease for its effect on another — speeds a drug into clinical trials and hastens approval from the U.S. Food and Drug Administration because detailed information on its pharmacology, formulation and safety is already available and has been reviewed.
“The way I think about it is when I get into the city for work, sometimes I wind up on the local train and it stops 20 times before I get into the city and sometimes you get that golden express train and there’s only one stop,” said MJFF CEO Todd Sherer, PhD. "That’s exactly what we’re trying to do here."
Read more about the STEADY-PD Phase II results.
Subscribe to the MJFF Parkinson’s Podcast Series.