Korsana Biosciences has emerged from stealth with US$175m to develop an Alzheimer’s antibody designed to boost amyloid plaque clearance.
The Waltham, Massachusetts-based biotech is focused on neurodegenerative disease.
Its lead programme, KRSA-028, is a next-generation shuttled monoclonal antibody targeting amyloid beta, a protein that can build up into plaques in Alzheimer’s.
The treatment uses the company’s THETA platform, which incorporates transferrin receptor (TfR1) and Fc engineering to improve delivery across the blood-brain barrier, the protective layer that controls what enters the brain from the bloodstream.
The company says KRSA-028 is designed to increase plaque clearance, lower the rate of amyloid-related imaging abnormalities (ARIA), changes seen on brain scans, and support low-volume subcutaneous dosing, given under the skin, rather than intravenous infusions.
The company was founded in 2024 with a US$25m seed investment and closed a US$150m Series A financing round in September 2025.
It has appointed Jonathan Violin as president and chief executive. Dr Violin has been a venture partner at Fairmount since 2023 and previously served as founding chief executive of Viridian Therapeutics from 2020 to 2023.
He was also founding chief executive of Dianthus Therapeutics and Quellis Biosciences, which merged into Astria Therapeutics.
Dr Violin said: “We are thrilled to announce the launch of Korsana with a mission to elevate expectations for patients suffering from devastating neurodegenerative diseases.
“In particular, Alzheimer’s disease represents a massive and growing unmet need, with the US patient population projected to double to approximately 13m by 2050.
“Only two disease-modifying therapies have been approved to treat Alzheimer’s, and both carry safety warnings, offer only modest efficacy, and impose a high burden of care.
“Patients deserve better options than what is currently available, and we believe our lead programme KRSA-028 can deliver a best-in-class product to treat Alzheimer’s.
“I am thrilled with the robust support of our mission by Korsana’s investors, and excited to build another leading biotechnology company in partnership with the team at Paragon Therapeutics.”
The Series A was co-led by Wellington Management and TCGX, with participation from J.P. Morgan Life Sciences Private Capital, Janus Henderson Investors, Sanofi Ventures, Foresite Capital and others.
The seed round came from Fairmount and Venrock Healthcare Capital Partners.
KRSA-028 was discovered in partnership with Paragon Therapeutics. The company is also advancing a pipeline of THETA-enabled therapies for other undisclosed neurodegenerative diseases.
The financing is expected to fund activities into 2028, including pharmacokinetics, CNS penetration and safety data from healthy volunteers expected in mid-2027, and initial proof-of-concept data showing amyloid plaque clearance in Alzheimer’s patients expected by the end of 2027.
Andrew Gottesdiener, partner at Venrock and co-founder and member of the board of directors of Korsana, said: “We believe Korsana is well positioned to overcome the limitations of not just first-generation Alzheimer’s therapies, but also of earlier shuttle technologies.
“Leveraging a well-established regulatory pathway, Korsana is advancing the next generation of therapies for Alzheimer’s disease and other neurodegenerative disorders, with a clear path to creating value for patients.
“We are thrilled to work with Korsana to build what I believe will become an important and valuable company. Together, we are committed to delivering better medicines to patients suffering from neurodegenerative diseases.”
