CSL Limited has entered an exclusive agreement with Alentis Therapeutics to co-develop and co-promote lixudebart, a potential first-in-class treatment for rare kidney and liver diseases. The company will pay Alentis an upfront sum of US$355 million, with potential milestone payments of up to US$1.2 billion as the program advances through clinical trials and toward commercialisation. Once approved and generating revenue, CSL and Alentis will split global profits 55 percent and 45 percent respectively.
Lixudebart is an investigational monoclonal antibody that targets claudin-1, a protein central to inflammatory and fibrotic signalling in multiple organs. By addressing both inflammation and fibrosis, two primary drivers of progressive kidney and liver damage, the drug’s design differs from existing standard-of-care options. This dual mechanism positions it as a potential first-in-class solution for patients with limited therapeutic choices.
The treatment is currently being tested in Phase 2 trials for ANCA-associated vasculitis with rapidly progressive glomerulonephritis (AAV-RPGN), a rare autoimmune disease in which the immune system attacks blood vessels in the kidneys. An interim analysis of 26 patients showed improvement in kidney function at 24 weeks, measured by eGFR and proteinuria. Earlier Phase 1b data demonstrated improved liver function in patients with advanced fibrosis, and the drug has shown a favourable safety and tolerability profile across studies. The FDA has granted it Orphan Drug designation for idiopathic pulmonary fibrosis.
CSL’s investment signals its strategic pivot into nephrology. The company has explicitly committed to building a leading global nephrology franchise, and lixudebart is central to that effort. CSL will fund all remaining development activities, including completion of the Phase 2 trial, a planned Phase 3 study in AAV-RPGN, and Phase 2 programs in two additional indications: focal segmental glomerulosclerosis (FSGS) and primary sclerosing cholangitis (PSC), a liver disease currently without approved therapies.
For investors, lixudebart represents a potentially transformative asset in a large, underserved market. AAV-RPGN and related glomerulonephritides affect millions globally, yet many patients progress to end-stage renal disease despite intensive immunosuppressive therapy. A successful first-in-class option could capture substantial commercial value. The 55-45 profit split gives CSL majority upside once commercialised, while the milestone structure provides downside protection if development encounters obstacles.
The key milestone to monitor is the Phase 3 trial in AAV-RPGN, which will determine whether lixudebart meets regulatory standards for approval. Success in the FSGS and PSC indications would unlock further revenue potential. This announcement is price sensitive and has been flagged as material by the ASX.
View the full ASX announcement (PDF)
About CSL Limited (ASX: CSL)
CSL Limited is a global biotechnology company that develops and delivers innovative biotherapies and vaccines. It is a leader in plasma-derived therapies and one of the largest influenza vaccine manufacturers worldwide.
If you would like to discuss this announcement, request a callback or call us on 1300 889 603.
