Cx621 is an allogeneic expanded adipose-derived stem cell (eASC) product candidate for the treatment of autoimmune diseases via a proprietary technique of intralymphatic administration. The promise of the intralymphatic route is that the systemic effect of the eASC’s occurs at the secondary lymphoid organs: draining lymph nodes and spleen. Recent preclinical and clinical experience with vaccines and antitumour agents indicates that intralymphatic administration is feasible and safe. Indeed, the subcutaneous lymph nodes are readily visible by ultrasound, as their paracortical area is hypoechoic. Injection of a superficial lymph node in the groin area can be performed very quickly, within minutes, even by doctors who have little experience with ultrasound. Furthermore, intralymphatic injection is relatively painless as lymph nodes are poorly innervated.
Phase I clinical trial
After obtaining positive results from toxicology, biodistribution and efficacy models in mice using human eASC’s via the intralymphatic route, TiGenix conducted a Phase I clinical study in 10 healthy volunteers, which was concluded in July 2012. The results of the Phase I study confirmed the safety, tolerance and the feasibility of injection into the inguinal ganglia. The confirmation of the safety of intra-lymphatic administration of expanded adipose-derived stem cells (eASCs) has potentially important clinical and commercial implications. It opens up the possibility of achieving efficacy at lower dosages which would further increase the safety profile of TiGenix’s eASCs, while also reducing the cost and improving margins. An additional benefit is that subcutaneous lymph nodes are superficial and readily visible by ultrasound, thus allowing for a rapid and easy injection.
The development of Cx621 is currently on hold while TiGenix focuses its resources on the development of Cx601 and Cx611.