Imaging Biomarker for Parkinson’s Clinical Trials Gains EMA Support

The Critical Path Institute (C-Path) — part of the Critical Path for Parkinson’s Consortium (CPP) — and Parkinson’s U.K. have garnered the support of the European Medicines Agency (EMA) for the use of an imaging biomarker that will help researchers conduct new treatment clinical trials for patients diagnosed with early-stage Parkinson’s disease .

The neuroimaging biomarker dopamine transporter imaging system is used as an exploratory biomarker for the early stages of Parkinson’s. CPP's ultimate goal is to achieve biomarker qualification with EMA and the US Food and Drug Administration (FDA).

"Parkinson's disease treatments are urgently needed, and shaving off time and cost serves to incentivize companies to invest in more trials,” said CPP's executive director Diane Stephenson. “More shots on goal mean more chances of getting approved drugs past the finish line."

This, in turn, would ultimately relieve trial sponsors of having to convince the regulators that the biomarkers are reliable and reproducible during clinical trials.

Dopamine transporter activity, as measured by single-photon emission computed tomography (SPECT) imaging, looks at the expression of dopamine nerve terminal function in the living brain. Low levels of the binding serve as a marker of the loss of dopamine nerve terminals, which is a hallmark of Parkinson’s. Use of the biomarker in the early stages of Parkinson’s will help identify patients who are likely to show clinical progression of motor symptoms.

Embedding biomarkers in clinical trials, with support from regulatory agencies could facilitate their use as both therapeutic and prognostic indicators. "This will all happen more quickly due to the significant progress we are making in sharing data across several major studies,” said Donald Grosset, a professor at the University of Glasgow, where Parkinson's research that is contributing data to CPP is being conducted. "This action from the EMA is certainly good news for the field."

In 2015, the FDA issued a letter of support for this same biomarker and its application in drug development. These more recent letters of support convey that the FDA and EMA both recognize the potential value of a biomarker and encourage its further evaluation.