Patients who rely on a Sanofi drug for Pompe disease — a rare, progressive muscle-wasting disorder — are being unsettled by reports of delays in getting their medicine.
The drug, Nexviazyme (also sold as Nexviadyme), is an enzyme replacement therapy that supplies an enzyme people with Pompe disease cannot make on their own; missed or delayed doses are a serious concern for a condition that steadily damages muscles, including those used for breathing. Patient advocates have reported shipment delays for some Nexviazyme deliveries and urged patients to confirm their upcoming shipments; it has not been confirmed whether Sanofi’s older Pompe drug, Lumizyme, is affected.
The manufacturing backdrop
The delays follow an FDA warning letter, issued in mid-2026 after a January inspection of a Sanofi facility in Waterford, Ireland. Based on available information, the situation appears to be a product-release and distribution-timing issue rather than a safety or quality problem with medicine that has already been released — but the scope and duration remain uncertain as the situation develops.
Why it matters
For rare-disease patients, supply interruptions carry outsized stakes: there are few or no alternatives, and consistent dosing is essential. Nexviazyme is a growing product for Sanofi — it generated €426 million in the first half of 2026, up about 14.5% — which makes reliable supply all the more important. Affected patients should contact their care team and Sanofi’s patient-support channels about their specific shipments.
This is a developing story and general information, not medical advice. Patients should not change treatment on their own — contact your healthcare provider about your medication supply.