[18F]Fluorothymidine PET / CT Imaging for Monitoring Treatment Response in Patients with Metastatic Breast Cancer Undergoing Treatment with Ribociclib and Paclitaxel

Status: Active


This trial studies how well [18F]fluorothymidine PET / CT imaging works in measuring tumor growth and changes in the tumor after the start of treatment in patients with metastatic breast cancer undergoing treatment with ribociclib and paclitaxel. Positron emission tomography / computed tomography (PET / CT) imaging is commonly used in staging cancers. [18F]-fluorothymidine (FLT) is a specialized radioactive drug that is used as an imaging agent for PET / CT scans that uses a small amount of radioactive material to image tissue using a PET / CT scanner which is specialized to detect a small radioactive signal. [18F]FLT is used to detect cell growth. [18F]FLT PET / CT may help determine if the tumor responds to therapy with ribociclib and paclitaxel and what changes occur in the tumor after each drug.

Eligibility Criteria

Inclusion Criteria

  • History of histologically or cytologically confirmed breast cancer, any estrogen receptor (ER), progesterone receptor (PR) or HER2 status is allowed as long as it expresses the Rb protein
  • At least one site of metastatic breast cancer that is outside of the liver and bone that is identified by standard imaging (e.g. CT, magnetic resonance imaging [MRI], fludeoxyglucose F-18 [FDG] PET/CT, ultrasound, x-ray) and is measurable as defined by Response Evaluation Criteria in Solid Tumors (RECIST) 1.1
  • Participants must be informed of the investigational nature of this study and provide written informed consent in accordance with institutional and federal guidelines prior to study-specific procedures
  • Patients must be candidates to receive treatment on the therapeutic trial UPCC06115, a phase I study of ribociclib (LEE011) and weekly paclitaxel

Exclusion Criteria

  • Females who are pregnant at the time of screening will not be eligible for this study, urine pregnancy test will be performed at screening in women of child-bearing potential
  • Inability to tolerate imaging procedures in the opinion of an investigator or treating physician
  • Serious or unstable medical or psychological conditions that, in the opinion of the investigator, would compromise the subject’s safety or successful participation in the study
  • Ineligible for the therapeutic trial UPCC 06115

Locations & Contacts


University of Pennsylvania / Abramson Cancer Center
Status: Active
Contact: David A. Mankoff
Phone: 215-615-3687

Trial Objectives and Outline


I. Measure changes in fluorothymidine F-18 ([18F]FLT) uptake in metastatic tumors before and during treatment with ribociclib (LEE011) only and associate these changes with response to ribociclib (LEE011)/paclitaxel therapy.

II. Measure changes in [18F]FLT uptake in metastatic tumors during and 2 days after treatment with ribociclib (LEE011) only and associate these changes with response to ribociclib (LEE011)/paclitaxel therapy.


Patient receive fluorothymidine F-18 intravenously (IV), and then after approximately 60 minutes undergo PET/CT for up to 3 hours at baseline, after 3 days of ribociclib therapy, and on day 1 of paclitaxel therapy.

Trial Phase & Type

Trial Phase

Phase I

Trial Type


Lead Organization

Lead Organization
University of Pennsylvania / Abramson Cancer Center

Principal Investigator
David A. Mankoff

Trial IDs

Primary ID UPCC 11115
Secondary IDs NCI-2019-06638
Clinicaltrials.gov ID NCT02608216