Oyster Therapeutics, a London-based startup focused on tau-targeting degraders, has raised an extension of its Series A round, bringing in $60 million. The funding is intended to support development of oral drugs designed to eliminate disease-causing forms of tau while sparing healthy tau. The company’s lead program uses a targeting moiety for tau paired with an enzyme that tags the protein for intracellular destruction. Oyster says it incorporates a linker strategy engineered to split into two small molecules after entering the body to improve brain penetration, addressing limitations seen with earlier tau degraders and biologics. In the competitive tau landscape, Oyster’s financing arrives amid ongoing efforts and setbacks across the field. For investors, the round highlights continued appetite for differentiated delivery and molecular-selection strategies in neurodegeneration even after prior clinical disappointments.