Treatment of delayed?union fractures of long bones with minimally invasive administration of allogeneic bone?forming cells differentiated from mesenchymal stem cells: a pilot clinical trial

Abstract

Although bone has remarkable intrinsic capacity to repair naturally after fracture, approximatively 5 to 15% of the fractures do not heal appropriately, resulting in delayed?unions (DU) or non?unions. These complications result in impaired quality of life for the patient and high socioeconomic burden. Current approaches for the treatment of an impaired fracture healing involve invasive surgery, which is painful, induces serious complications in up to 20?30% of patients and prolongs rehabilitation time. To address this unmet medical need, we developed ALLOB, an injectable allogeneic cell therapy product constituted of bone?forming cells derived from bone marrow mesenchymal stem cells (MSC). It displays potent bone formation and repair properties in relevant in vivo mouse models. ALLOB can be administered locally by a minimally invasive injection thereby preventing the need for additional surgery. The present first?in?man clinical trial was designed to evaluate the safety and efficacy of ALLOB, given as a single percutaneous administration, in patients diagnosed with noninfected DU fracture of long bones.