Cytopharmaceuticals: An emerging paradigm for drug delivery

Cytopharmaceuticals, in which drugs/nanomedicines are loaded into/onto autologous patient- or allogeneic donor-derived living cells ex vivo, have displayed great promise for targeted drug delivery in terms of improved biocompatibility, superior targeting, and prolonged circulation. Despite certain impressive therapeutic benefits in preclinical studies, several obstacles retard their clinical application, such as the lack of facile and convenient methods of carrier cell acquisition, technologies for preparing cytopharmaceuticals at scale with undisturbed carrier cell viability, and modalities for monitoring the in vivo fate of cytopharmaceuticals. To comprehensively understand cytopharmaceuticals and thereby accelerate their clinical translation, this review covers the main sources of various cytopharmaceuticals, technologies for preparing cytopharmaceuticals, the in vivo fate of cytopharmaceuticals including carrier cells and loaded drugs/nanomedicines, and the application prospects of cytopharmaceuticals. It is our hope that this review will elucidate the bottlenecks associated with cytopharmaceutical preparation, leading to the acceleration of future industrialization of cell-based formulations.