UniQure paused mid‑ and high‑dose cohorts in its AAV gene‑therapy study for Fabry disease after patients developed dose‑limiting liver toxicities. Company filings and trial updates show two patients at the 4×10^13 gc/kg dose experienced grade‑3 elevations in liver enzymes, prompting an immediate dosing suspension and safety review. The firm cited standard toxicity management steps and protocol amendment planning. The pause follows recent industry scrutiny of systemic AAV vectors and dose‑related hepatotoxicity seen across multiple programs. UniQure’s action will drive a re‑examination of dose selection, monitoring schedules and stopping rules in ongoing rare‑disease gene therapy trials. Regulators and investors will be watching amendments and safety data before enrollment or dose escalation resumes.