Note 9 – Subsequent Events

On November 9, 2025, the Company presented new data and analyses from the Phase 2 ALXN1840-WD-204 copper balance study at the American Association for the Study of Liver Diseases (AASLD) - The Liver Meeting® 2025. In an oral presentation titled “Rapidly Improved Cu Balance in Wilson Disease Patients on Tiomolybdate Choline,” Professor Aftab Ala, MBBS, M.D., FRCP, Ph.D., Professor of Hepatology and Consultant Hepatologist at the Institute of Liver Studies at King’s College Hospital in London, shared results showing that treatment with ALXN1840 (tiomolybdate choline) led to a rapid and sustained improvement in daily copper balance in patients with Wilson disease, primarily through increased fecal copper excretion.

The mean daily copper balance among patients treated with ALXN1840 in the study (n=8) was significantly lower - indicating improvement - compared with their pre-treatment baseline. Copper balance improved both during the initial 15 mg once-daily dosing period (days 1-28) and over the entire treatment duration (days 1-39), which included patients receiving either 15 mg every other day or 30 mg once daily.