Inauguration of UCB’s Genesis gene therapy facility in Braine l’Alleud, delivered by BESIX

On 24 April 2026, the new Genesis gene therapy facility on UCB’s Braine l’Alleud campus was officially inaugurated, in the presence of Her Royal Highness Princess Astrid and Pierre Yves Jeholet, Vice-President of the Walloon Government and Minister for the Economy, Industry and Employment.  

BESIX was appointed to the project in 2022, with a clear mission: build a facility capable of supporting UCB’s ambition to develop and manufacture gene therapies in house, and do it without compromise on quality, safety or timing. The result is a 17,000 m² building that brings together laboratories, clinical manufacturing areas and offices, all designed to work as one coherent whole.

Inside, the Genesis facility reflects the complexity of the work it will host. A 1,200 m² pilot plant supports clinical manufacturing, using flexible single use bioreactors and highly automated fill and finish lines. These production spaces sit alongside advanced analytical and process science laboratories, making it easier to move from research into manufacturing without friction. The facility is supported by a fully integrated digital ecosystem with thousands of automation points, all anticipated and embedded during the construction phase. 

For the BESIX teams, the challenge lay in translating specific pharmaceutical requirements into a building that performs perfectly, day after day. Tight tolerances, controlled environments and smooth integration of structure and technology were non negotiable. Prefabricated concrete elements played a key role in keeping the project on track. 

At peak times, more than 400 people were working on the project, requiring constant coordination and a strong focus on safety. All of this took place on an active campus, which meant construction had to move forward while respecting ongoing operations around it.

Sustainability was another guiding principle from the start. The building has been designed to achieve BREEAM “Excellent” certification, with careful attention to energy use, materials and long term performance. It was also built with the future in mind, with space set aside for additional manufacturing capacity and possible extensions as UCB’s activities grow. 

The inauguration of the Genesis facility marks an important milestone for UCB and for BESIX, reaffirming BESIX’s expertise in delivering complex, high value infrastructure in Belgium and internationally.