Protego Biopharma closed an oversubscribed $130 million Series B to advance PROT-001, an oral small-molecule kinetic stabilizer aimed at amyloid light-chain (AL) amyloidosis, into a pivotal trial planned for H2 2026. The financing will support clinical, CMC and expanded pipeline work on small-molecule pharmacological chaperones intended to stabilize misfolded immunoglobulin light chains and prevent amyloid deposition. Protego positions PROT-001 as a disease-modifying approach that stabilizes lambda light chains rather than relying solely on plasma-cell–directed therapies. CEO Brent Warner described the drug as designed to work in tandem with standard-of-care plasma-cell eradication strategies and to address residual toxic light-chain production that contributes to cardiac and systemic amyloid burden. Investors and industry players will watch whether Protego’s small-molecule stabilizer can reproduce the clinical benefits of transthyretin stabilizers in an AL indication and how the company manages CMC and regulatory expectations for an oral therapy intended for a rare, complex protein-misfolding disease.