Pilot Study of 18F Fluoropaclitaxel (FPAC)
Multidrug resistance (MDR) is a cause of treatment failure in many cancer patients. MDR refers to a phenotype whereby a tumor is resistant to a large number of natural chemotherapeutic drugs. Having prior knowledge of the presence of such resistance would decrease morbidity from unsuccessful therapy and allow for the selection of individuals who may benefit from co-administration of MDR inhibiting drugs. The Tc-99m labeled single photon emitting radiotracers sestamibi and tetrofosmin have shown some predictive value. However, positron-emitting (PET) radiotracers, which allow for dynamic, quantitative imaging, hold the promise of more accurate and specific identification of MDR tumors.
To obtain human safety data, to demonstrate imaging feasibility with FPAC, to obtain human biodistribution and to obtain preliminary evidence of breast tumor uptake concordance with response to therapy.
|Study Design:||Intervention Model: Single Group Assignment
Masking: Open Label
|Official Title:||Pilot Study of 18F Fluoropaclitaxel (FPAC) in Breast Cancer Patients and Normal Volunteers: Dosimetry and Imaging Feasibility|
- Imaging feasibility and dosimetry [ Time Frame: <6months ] [ Designated as safety issue: No ]
|Study Start Date:||May 2005|
|Study Completion Date:||March 2008|
|Primary Completion Date:||March 2008 (Final data collection date for primary outcome measure)|
Drug: 4- [F-18] fluoropaclitaxel
18F flouropaclitaxel (FPAC) distribution in malignant tumors is expected to be similar to that of paclitaxel. It is proposed that by monitoring the influx and efflux of FPAC in vivo using PET imaging, we will be able to determine if a tumor retains the drug (is drug sensitive) or pumps it out (is drug resistant). The efflux rate of FPAC in the tumor should be proportional the amount of Pgp present and therefore should be a predictor of treatment failure. If this method is successful at identifying MDR, patients can be spared a course of ineffective chemotherapy and can be started on alternative drugs or, if available, an effective MDR modulator can be administered prior to treatment.
In order to validate the biodistribution in non-human primate, 3 normal volunteers will be recruited to participate in a dosimetry PET imaging protocol.
Often, patients with breast cancer are treated with chemotherapy prior to definitive surgical removal of the primary tumor. Three patients with breast cancer who are candidates for this neoadjuvant chemotherapy will also be recruited to participate in this study, in order to demonstrate the feasibility of tumor imaging. As these patients will be receiving chemotherapy (likely paclitaxel), a preliminary correlation with FPAC uptake and tumor response can also be attempted in this pilot study.
--To obtain human dosimetry and monitor for potential physiologic effects following 4-[F-18] fluoropaclitaxel (FPAC) administration
- a.To characterize tracer uptake in tumors and normal tissues and develop robust methods for analysis of FPAC kinetics in breast tumors
- b.To optimize the imaging protocol for FPAC, and, if feasible, reduce to 1 or 2 static scans
|United States, Virginia|
|Virginia Commonwealth University|
|Richmond, Virginia, United States, 23298|
|Principal Investigator:||Harry D. Bear, MD, PhD||Virginia Commonwealth University|