The European Medicines Agency’s (EMA) Committee for Medicinal Products for Human Use (CHMP) has recommended granting a marketing authorization in the EU for Waskyra to treat people aged 6 months or older with Wiskott-Aldrich syndrome (WAS) who have a mutation in the WAS gene.

WAS is a rare genetic immunodeficiency, seen almost exclusively in males, that prevents a child’s immune system from functioning properly. It is caused by abnormalities in the gene that produces the WAS protein found in blood cells and certain immune cells. Without normal immune cells, patients are at constant risk for a range of infections, including pneumonia and cytomegalovirus, and eczema. They also bruise and bleed easily and are at higher risk of developing some types of cancer, such as lymphoma. 

Waskyra (etuvetidigene autotemcel) is used to treat patients for whom a hematopoietic stem cell transplantation is appropriate, but no suitable stem cell donor is available, making it an unmet medical need. 

It is a gene therapy medicine that is made from stem cells that are collected from the patient’s blood. The cells are genetically modified in the laboratory so that they can produce a functional WAS protein. It is given once by infusion into a vein.

EMA’s recommendation is based on data from a clinical development program involving 27 patients with WAS. The primary study was a single-arm clinical trial in 10 children aged 1-9 years that was supported by data from another clinical trial and an expanded access program comprising 17 patients aged 1-35 years. The data indicated that the annual rate of severe infections decreased from two events in the 12 months prior to treatment to 0.15 event 1-2 years post-treatment and to 0.12 event 2-3 years post-treatment. In addition, the rate of moderate and severe bleeding episodes decreased from two events in the 12 months prior to treatment to 0.16 event 2-3 years post-treatment. 

The most common side effects reported were due to the procedures and medications required to receive the treatment, such as the conditioning regimen and pretreatment, and administration site conditions.

The opinion adopted by the CHMP marks an important milestone in potentially expanding available treatment options for children with WAS. The opinion will now be sent to the European Commission for the adoption of a decision on an EU-wide marketing authorization.

Waskyra was supported through an EMA pilot offering support to academic and nonprofit developers of advanced therapy medicinal products addressing unmet medical needs.