CSL and Alentis Therapeutics have entered an exclusive global collaboration to co-develop and co-promote lixudebart, an investigational monoclonal antibody targeting claudin-1 for rare kidney, liver and other diseases. CSL shares rose after the deal was announced. CSL will pay Alentis US$355 million upfront and fund ongoing and planned clinical development, while Alentis is eligible for up to US$1.2 billion in commercial milestone payments. The agreement is valued at up to US$1.6 billion before development funding, and global profits after commercialization will be split 55% to CSL and 45% to Alentis. Formerly known as ALE.F02, lixudebart is in a Phase 2 trial for AAV-RPGN, a rare autoimmune kidney disease that can cause irreversible damage and end-stage renal disease, with planned development in FSGS and PSC. The FDA granted the drug orphan drug designation for idiopathic pulmonary fibrosis in 2024.