The Phase 2a study EXIST (EXIdavnemab Synucleinopathy Trial), is a randomized, double-blind, placebo-controlled study in Parkinson's disease patients to evaluate the safety and tolerability of exidavnemab. The study is conducted in Europe and at least 24 patients will be recruited in ,divided into two cohorts of 12 (Cohort 1 and Cohort 2). Participants in Cohort 1 will receive either a lower dose of exidavnemab or placebo and participants in Cohort 2 will receive either a higher dose of exidavnemab or placebo. In addition to the primary endpoints, a broad range of biomarkers will be evaluated, in plasma, cerebrospinal fluid (CSF) and using digital measurements.

"We are very excited that the first patient with Parkinson's disease has now been dosed in the EXIST Phase 2a study with exidavnemab," said Gunilla Osswald, CEO at BioArctic. "It marks an important next step on BioArctic's pioneering journey to broaden our research portfolio and help more patients and families with different neurological disorders to a better life."

Recently, the results of two separate Phase 1 studies of exidavnemab, conducted in collaboration with AbbVie, were published in The Journal of Clinical Pharmacology. The results showed that exidavnemab is generally well-tolerated, with an excellent half-life of approximately 30 days. These data together with the high affinity and selectivity toward the pathological aggregated forms of α-synuclein, key to maintaining a high target binding in the brain, laid the foundation for the Phase 2a study.

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This release discusses investigational uses of an agent in development and is not intended to convey conclusions about efficacy or safety. There is no guarantee that such investigational agents will successfully complete clinical development or gain health authority approval.

The information was released for public disclosure, through the agency of the contact person below, on December 5, 2024, at 08:00 a.m. CET.

For further information, please contact:
Oskar Bosson, Vice President Communications and Investor Relations
E-mail: oskar.bosson@bioarctic.se
Phone: +46 70 410 71 80

About Exidavnemab
Exidavnemab is a monoclonal antibody drug candidate that is designed to selectively bind and eliminate pathological aggregated forms of alpha-synuclein such as oligomers and protofibrils as well as fibrillar forms, all of which are believed to play a role in neurodegenerative disorders including Parkinson's disease. The goal is to develop a disease modifying treatment that stops or slows down the progression of Parkinson's disease or other synucleinopathies. 

About BioArctic AB
BioArctic AB (publ) is a Swedish research-based biopharma company focusing on innovative treatments that can delay or stop the progression of neurodegenerative diseases. The company invented Leqembi® (lecanemab) - the world's first drug proven to slow the progression of the disease and reduce cognitive impairment in early Alzheimer's disease. Leqembi has been developed together with BioArctic's partner Eisai, who are responsible for regulatory interactions and commercialization globally. In addition to Leqembi, BioArctic has a broad research portfolio with antibodies against Parkinson's disease and ALS as well as additional projects against Alzheimer's disease. Several of the projects utilize the company's proprietary BrainTransporter™ technology, which has the potential to actively transport antibodies across the blood-brain barrier to enhance the efficacy of the treatment. BioArctic's B share (BIOA B) is listed on Nasdaq Stockholm Large Cap. For further information, please visit www.bioarctic.com.