High target affinity and specificity makes antibodies very suitable tumor-targeting vehicles for imaging and therapeutic applications. This enables a theranostic approach of imaging targeted drug delivery in oncology and opens the way for personalized medicine, predicting drug delivery, response, and treatment outcome in the individual patient.

In an article published in the October 29, 2014 edition of Current Drug Targets, Mark Rijpkema, Otto Boerman and Wim Oyen of the Department of Radiology and Nuclear Medicine at the Radboud University Medical Center, Nijmegen, The Netherlands, conclude that of the currently available molecular imaging techniques, single-photon emission computed tomography (SPECT) and positron emission tomography (PET) are the best suited imaging techniques to visualize and determine drug delivery to the target tissue quantitatively.

The scientists suggest that using the same antibody for imaging and targeted therapy may eliminate some limitations of antibody-based molecular imaging and therapy, including heterogeneous antigen expression and poor accessibility. However observe that the challenges of this approach remain in the pharmacokinetic behavior of radiolabeled antibodies and antibody-drug-conjugates.

MabPlex
 

Despite these challenges, Boerman, et al, believe that by using antibodies as multimodal vehicles carrying both a diagnostic agent and a therapeutic agent, novel opportunities are at the horizon.

In their review, the authors discuss both the challenges and the opportunities of using radiolabeled antibodies for image-guided drug delivery.