Alexion Pharmaceuticals Inc. / Wilson Therapeutics AB

Wilson Disease

Disease Overview

Wilson disease is an autosomal recessive disorder of copper metabolism caused by mutations in ATP7B, leading to toxic copper accumulation in the liver, brain and other organs. Patients typically present in adolescence or young adulthood with hepatic, neurologic or psychiatric manifestations and require lifelong chelation or zinc therapy; untreated disease is uniformly fatal from liver failure or neurologic decline. It is a textbook ultra-rare metabolic disorder with a stable, identifiable patient population.

Competitive Landscape

At deal time the Wilson disease standard of care was decades old: D-penicillamine (Cuprimine, Depen), trientine hydrochloride (Syprine, marketed by Valeant/Bausch and notorious for ~$300K/yr pricing controversy), and zinc acetate (Galzin) — all chelators with significant tolerability and adherence issues. Wilson Therapeutics' WTX101 (bis-choline tetrathiomolybdate) was positioned as a first-in-class de-coppering agent with faster control of free copper and a cleaner neurologic safety profile than penicillamine, supported by a 28-patient Phase 2 in which ~80% of patients hit the primary endpoint at 24 weeks. Piper Jaffray called the deal a strong fit, noting unmet need despite two approved-but-marginally-effective therapies. Post-deal, AstraZeneca (which acquired Alexion in 2021) ultimately walked away from WTX101/ALXN1840 in 2023 after FDA pushback, ceding the field — Orphalan's Cuvrior (trientine tetrahydrochloride, FDA approved May 2022) became the most recent advance, and Alexion-acquired ALXN1840 was discontinued, validating the difficulty of disrupting decades-old chelators.