Simvastatin Fails to Slow Parkinson’s Progression, Trial Data Shows

Simvastatin, a widely-used cholesterol-lowering medication, failed to slow the progression of Parkinson’s disease, according to data from a Phase 2 trial.

Based on these findings, it was decided that a future Phase 3 study assessing the safety and efficacy of simvastatin in these patients would not be justified.

Data from the study, called PD-STAT (NCT02787590), were presented at the Movement Disorder Society (MDS) Virtual Congress 2020, in a poster titled “Simvastatin as a neuroprotective treatment for Parkinson’s disease (PD STAT): results of a double-blind, randomised, placebo-controlled futility study.”

The use of statins — a class of drugs normally prescribed to lower the levels of cholesterol in the blood — has been associated with a lower incidence of Parkinson’s. Moreover, studies in cellular and animal models have shown that statins can influence some of the signaling cascades that are thought to be involved in the development of Parkinson’s.

Simvastatin in particular also has been shown to lower the rate of brain shrinkage (brain atrophy) in patients with secondary progressive multiple sclerosis (MS), another type of neurodegenerative disease.

For these reasons, simvastatin was selected by The Cure Parkinson’s Trust’s International Linked Clinical Trials initiative to be tested in a clinical study. The initiative was created to identify new compounds with biochemical properties that have the potential to slow, halt, or even reverse Parkinson’s progression.

PD-STAT was launched in 2015 to investigate whether simvastatin would be superior to a placebo at slowing the neurological and physical decline of people with moderate Parkinson’s, as measured by the MDS-Unified Parkinson’s Disease Rating Scale (MDS-UPDRS), over a period of two years. At its start, it was the largest academic study in the U.K. investigating neuroprotective medicines in Parkinson’s.

During the study, which recruited a total of 235 participants (median age 62 years) from 23 hospitals across England, patients were randomly assigned to receive simvastatin — at a dose of 40 mg in the first month, followed by 80 mg thereafter — or a placebo, both given orally, for a period of 24 months (two years). Participants also had a final study visit at month 26.

Among the patients enrolled, 216 progressed to the higher dose; a total of 52 of those participants (24%) discontinued the study medication before 24 months.

Data from PD-STAT showed that, compared with a placebo, simvastatin was “futile” at slowing disease progression in patients with moderate Parkinson’s. Based on these findings, the researchers determined that a subsequent Phase 3 trial assessing the safety and efficacy of simvastatin in these patients would not be justified.

“Although the result of PD-STAT did not show that simvastatin has promise as a protective therapy in Parkinson’s, it is very helpful to be able to present robust data and a definitive answer on this important question,” Camille Carroll, MD, PhD, who led PD-STAT, said in a press release. Carroll, an associate professor at the University of Plymouth’s Faculty of Health, is an honorary consultant neurologist at the University Hospitals Plymouth NHS Trust.

“There are lots of positives to come out of this study, particularly the extent to which we were able to involve participants across the country, and the very positive feedback received from them and staff in the hospitals involved,” Carroll said.

“PD-STAT has taught us a huge amount about how to improve the way we design and deliver clinical trials in Parkinson’s and this knowledge will be very useful in designing future trials,” she added.

According to Katherine Bewsey, one of the patients in PD-STAT, it overall was a positive experience to participate in a clinical trial attempting to validate a well-known medication to slow Parkinson’s progression.

“Taking part in this trial was very easy, all the people I dealt with were pleasant and keen to make sure I was always comfortable. I also received a few extra check-ups as a result of taking part, which was a plus,” Bewsey said. “All in all, I’d be very happy to recommend taking part in a similar trial to other people.”

The importance of PD-STAT, despite its negative findings, also was shared by Richard Wyse, director of research and development at The Cure Parkinson’s Trust, who highlighted that this study could provide the foundation for future trials investigating the therapeutic potential of new medications for Parkinson’s.

“This has been an important trial as we have not only tested a study medication and evaluated novel outcomes, but we have also used this as an opportunity to understand the impact of involvement in clinical trials on participants and their loved ones,” Wyse said. “As a result of this trial we now have motivated an active network of researchers who are keen to participate in running future studies of drugs of interest, evaluated and prioritized through the International Linked Clinical Trials process.”