Companion Imaging Agents

Providing a current picture of a patient’s disease status

Our technology allows us to create companion imaging agents intended for use with each of our SMDCs. To create our companion imaging agents, we replace the drug payload of the SMDC with an imaging agent (radionuclide) that can be viewed with widely available nuclear imaging equipment.

Because the targeting ligand used on the companion imaging agent is identical to that found on the therapeutic SMDC, our companion imaging agents allow us to obtain real-time images of tumors anywhere in the body that express the target for that particular SMDC. 

Our goal is to identify the patients most likely to benefit from treatment

These companion imaging agents also allow for the screening of large patient populations to select diseases where a high percentage of the patient population have tumors or diseased cells that express the molecular target.

Companion imaging agents may also enable us to expand the use of our SMDCs to cancer indications where the percentage of patients who express a given receptor target of interest may be relatively low and help to identify patients who will most likely benefit from treatment with our SMDCs.

Validating drug development

The information provided by our companion imaging agents is used throughout the development of every new SMDC. In both preclinical and clinical trials, a companion imaging agent is used to evaluate targeting of our SMDC to specific tissues and cells and to identify the most appropriate patient population for clinical testing. The diagnostic images below were obtained following administration of our folate receptor-targeted imaging agent etarfolatide (EC20). The patient on the left shows no etarfolatide-positive tumor (negative profile). The patient on the right shows etarfolatide-positive tumors (positive profile).