The European Medicines Agency (EMA) has blocked the approval of donanemab (Kisunla), a drug for Alzheimer's patients, despite its approval in the US and UK. Concerns over potentially fatal side effects, particularly amyloid-related imaging abnormalities (ARIA), led to this decision. The drug showed promise in slowing dementia progression but poses risks, especially for certain genetic carriers. Experts express disappointment but emphasize patient safety. Eli Lilly plans to appeal the EMA's decision, hoping to provide access to the treatment for early-stage Alzheimer's patients in Europe.