ADIPOA-2 will build on the work of ADIPOA to deliver a large-scale clinical trial in regenerative medicine for Osteoarthritis. The purpose of the project is to design and implement a phase IIb study to assess the safety and efficacy of Autologous adipose-derived mesenchymal stromal cells (ASCs) in the treatment of advanced OA of the knee. The cells will be prepared from samples of adipose tissue harvested from patients by lipoaspiration.