Validation of Uptake of a VEGF-targeted Optical Fluorescent Imaging Tracer in Surgical Specimens of Breast Cancer and Application of Pre- and Intra-operative Human Molecular Fluorescence Imaging Techniques. A multicenter feasibility study

To improve breast cancer management, there is a need for better visualization
of presence and extent of breast cancer. Molecular imaging of breast cancer
associated targets is a promising technique to accommodate this need. Vascular
Endothelial Growth Factor (VEGF), which is differentially expressed in normal
versus (pre)malignant breast tissue, has proven to be a valid target for
molecular imaging. Fluorescent labeling of bevacizumab (a VEGF targeting
humanized monoclonal antibody currently used in therapy) has potential
advantages over radioactive labeling in view of radiation safety,
infrastructure, costs and stability. Therefore, the fluorescent tracer
bevacizumab-IRDye 800CW has been developed and was recently approved to be
administered to patients in a tracer dose. To detect this tracer in vivo,
intra-operative Multispectral Fluorescence Reflectance Imaging (MFRI) cameras
are available at both institutions. Advanced optical imaging systems are
operational at both centers for pre-operative imaging. These systems can be
evaluated in clinical studies with this new fluorescent tracer.

The primary objectives of this study are (1) to assess uptake of
bevacizumab-IRDye 800CW in breast cancer, surrounding tissue and lymph nodes as
measured in surgical specimens after a single intravenous administration of 4.5
mg and (2) to evaluate safety aspects of the tracer.
Secondary objectives are to assess the ability of pre- and intra-operative
optical fluorescence imaging systems to detect a fluorescent signal from
bevacizumab-IRDye 800CW in vivo and explore their potential utility.

In this non randomized, non blinded, prospective, multicenter feasibility
study, the new VEGF-targeting fluorescent tracer (bevacizumab-IRDye800CW) will
be administered to patients with proven breast cancer. In both centers, a part
of the surgical specimen will be investigated extensively to determine uptake
of bevacizumab-IRDye800CW in tumor and surrounding tissue (localization,
(semi-) quantification). Also, the MFRI camera will be used in both centers
during the surgical procedure to visualize a fluorescent signal of the tumor,
surrounding tissue and lymph nodes (localization, semi-quantification). In both
centers, optical imaging modalities will be used to image patients at several
time points after administration and before surgery to visualize, localize and
semi-quantify a fluorescent signal in tumor tissue, tumor margins, healthy
tissue and lymph nodes to explore pharmacokinetics and optimal imaging time
points.

All included patients receive an injection with fluorescently labeled
bevacizumab (5mg) once.
Blood samples will be taken at 4 time points. The first and second time, 4mL
blood will be drawn. The 3rd time, 12 mL will be drawn. The 4th time 8 mL will
be drawn.

In this study, safety data related to (the administration of) the tracer will
be collected and evaluated. Based on pre-clinical experiments, toxicity studies
and the low administered dose, no adverse events are expected. Given the first
application of this tracer in man all safety precautions will be taken into
account. To do so, the first 3 patients will be treated with a time interval of
two weeks and the first 5 patients will be treated in one center only (UMC
Groningen). Also, immunogenicity will be determined in blood samples.
The risks related to the blood withdrawal are considered minimal, only 12 ml of
blood is withdrawn (in comparison, 500ml of blood is withdrawn during a blood
donation), divided over four visits.
The risks related to the use of the MFRI camera are considered minimal. A small
increase in surgical procedure time is expected. Trained personnel to work with
the camera are available in the operating room. Risks related to the use of the
pre-operative imaging systems are considered minimal, as the systems are
approved to be used in clinical research studies.
The time investment of the subjects is considered reasonable. The procedures
at the screening visit will take about 1 hour, at the tracer administration
visit about 6 hours, at the tracer uptake visit about 1 hour and before surgery
about 1 hour.