1. Chimie ParisTech, PSL University, CNRS, Institute of Chemistry for Life and Health Sciences, Laboratory for Inorganic Chemical Biology, 75005 Paris, France.
2. Institute of Inorganic Chemistry, Faculty of Chemistry, University of Vienna, Währingerstraße 42, 1090 Vienna, Austria.
3. Vienna Doctoral School in Chemistry, University of Vienna, Währingerstraße 42, 1090 Vienna, Austria.
4. Division of Nuclear Medicine, Department of Biomedical Imaging and Image Guided Therapy, Medical University of Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria.
5. Joint Applied Medicinal Radiochemistry Facility, University of Vienna, Währingerstraße 42, and Medical University of Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria.
† Have contributed equally to the work.
Photodynamic Therapy (PDT) is an approved treatment modality, which is presently receiving great attention due to its limited invasiveness, high selectivity and limited susceptibility to drug resistance. Another related research area currently expanding rapidly is the development of novel theranostic agents based on the combination of PDT with different imaging technologies, which allows for both therapy and diagnosis. This combination can help to address issues of suboptimal biodistribution and selectivity through regional imaging, while therapeutic agents enable an effective and personalized therapy. In this review, we describe compounds, whose structures combine PDT photosensitizers with different imaging probes - including examples for near-infrared optical imaging, magnetic resonance imaging (MRI) and nuclear imaging (PET or SPECT), generating novel theranostic drug candidates. We have intentionally focused our attention on novel compounds, which have already been investigated preclinically in vivo in order to demonstrate the potential of such theranostic agents for clinical applications.
Keywords: Magnetic Resonance Imaging (MRI), Nuclear Imaging (PET, SPECT), Optical Imaging, Photodynamic Therapy (PDT), Theranostics