CSL Strikes Up to $1.6 Billion Deal with Alentis to Co-Develop Rare Disease DrugHealth

<h2>A potential first-in-class treatment</h2> The agreement gives CSL the right to jointly develop and commercialise lixudebart, previously known as ALE.F02, a potential first-in-class therapy being studied for rare kidney and liver diseases.

Lixudebart is currently in a Phase 2 trial for a rare autoimmune kidney disease that can cause irreversible kidney damage and end-stage renal disease. In 2024, the US Food and Drug Administration granted the drug orphan drug designation — a special status for investigational therapies intended to prevent, diagnose or treat rare diseases or conditions — for idiopathic pulmonary fibrosis, a chronic lung disease.

The two companies also plan to advance the treatment as a potential therapy for focal segmental glomerulosclerosis, known as FSGS, a chronic kidney disease, and for primary sclerosing cholangitis, or PSC, a chronic liver disease for which there is currently no approved treatment.

<h2>Shared profits after launch</h2> Once the drug is commercialised, global profits will be shared 55 per cent to CSL and 45 per cent to Alentis, the companies said.

The milestone payments, worth up to $1.2 billion, are tied to commercial achievements rather than development steps, meaning they would be paid as the drug reaches defined sales or commercial targets following any approval. The upfront payment of $355 million secures CSL&#8217;s position in the co-development and co-promotion arrangement.

Rare-disease therapies target small patient populations, but such medicines often address conditions with few or no existing treatment options. The agreement comes as lixudebart moves through mid-stage clinical testing, a point at which biotech partnerships are commonly structured around shared development costs and shared commercial rights.

For Alentis, the deal pairs its research programme with CSL&#8217;s global development and commercial scale, while giving the Australian company access to a potential first-in-class asset in a therapeutic area where new options remain urgently needed.