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 kidney, liver and other diseases. Alentis will receive an initial US$355 million payment and up to US$1.2 billion in commercial milestones, while CSL will fund the ongoing Phase 2 RENAL trial, a planned Phase 3 AAV-RPGN trial, Phase 2 studies in FSGS and PSC, and other supporting development. Once commercialized, global profits will be split 55% to CSL and 45% to Alentis. Lixudebart is being evaluated in AAV-RPGN, a rare autoimmune disease involving rapid kidney-function loss, and the companies plan to advance it in focal segmental glomerulosclerosis and primary sclerosing cholangitis. The therapy selectively targets exposed claudin-1, which is involved in inflammatory and fibrotic signaling. An interim analysis of 26 AAV-RPGN patients showed promising kidney-function improvement at 24 weeks, while a Phase 1b study in 41 patients with advanced liver fibrosis reported improved liver function at six weeks. Lixudebart has also received FDA Orphan Drug designation for idiopathic pulmonary fibrosis.