A Phase 2a trial of a new Parkinson’s disease drug has passed an interim safety review, allowing researchers to proceed with higher dose testing.
The EXIST study is assessing exidavnemab as a potential treatment for Parkinson’s disease and multiple system atrophy (MSA)—a rare disorder where nerve cells in multiple areas of the brain progressively deteriorate.
The first cohort received a lower dose of exidavnemab or a placebo in patients with Parkinson’s disease.
Following a positive safety review, two additional cohorts will now begin, testing a higher dose in patients with Parkinson’s disease and MSA.
Swedish biotech firm BioArctic, which is developing the drug, confirmed the progression of the trial following the review.
Gunilla Osswald, chief executive at BioArctic, said: “Exidavnemab is BioArctic’s second disease-modifying treatment for severe brain diseases, building on a similar scientific approach as Leqembi.
“Both originate from our antibody platform, selectively targeting aggregated, toxic misfolded proteins.
“I am pleased that the interim safety review of our phase 2a study EXIST of exidavnemab showed a good safety and tolerability profile as expected, supporting progression into higher doses in both Parkinson’s disease and MSA.”
The EXIST study (EXIdavnemab Synucleinopathy Trial) is a randomised, double-blind, placebo-controlled trial evaluating the safety, tolerability and pharmacokinetics—how the drug is processed in the body.
It also includes the measurement of a wide range of biomarkers in plasma, cerebrospinal fluid, and through digital assessments.
Exidavnemab is a monoclonal antibody—a lab-produced protein designed to bind to specific targets in the body.
It selectively targets aggregated forms of alpha-synuclein, a misfolded protein that damages nerve cells in diseases such as Parkinson’s and MSA, while sparing normal forms of the protein.
The drug is being developed as what BioArctic describes as a disease-modifying treatment for synucleinopathies—conditions involving harmful build-up of alpha-synuclein.
By binding to and clearing these toxic aggregates, it aims to help preserve nerve cell function and slow disease progression.
Exidavnemab has recently received orphan drug designation in the US and a positive opinion for orphan medicinal product designation in the EU for the treatment of MSA—designations awarded to drugs intended for rare diseases affecting small patient populations.
