A Study of the Effects of Inhibiting Platelet Function on Circulating Cancer Cells in Breast Cancer Patients

The Impact Of Platelet Function Inhibition On Circulating Cancer Cells In Metastatic Breast Cancer Patients

The purpose of this study is to determine the effects of Plavix and aspirin in women with metastatic breast cancer.

Study Overview

• Status: Terminated
• Conditions: Breast Neoplasms
• Intervention / Treatment: Drug: Aspirin; Drug: Plavix

• Study Type: Interventional
• Enrollment (Actual): 48
• Phase: Phase 2

Contacts and Locations

Study Locations

• United States
  • Missouri
    • St. Louis, Missouri, United States, 63110
      • Washington University School of Medicine

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: Female

Description

Inclusion Criteria:

• Women with metastatic breast cancer who are completing planned course of chemotherapy with planned treatment break
• On stable hormone therapy for at least 2 months are also eligible for the study
• Estimated survival of at least 3 months
• No platelet inhibitor therapy within 1 month of study entry
• Platelets ≥ 100,000
• Coagulation screening tests within normal range (INR between 0.81 and 1.20)

• Normal kidney and liver function as defined by:

  • Aspartate aminotransferase(AST)/serum glutamic oxaloacetic transaminase (SGOT))/alanine aminotransferase(ALT) ≤ 2 x Institutional Normal
  • Creatinine ≤ 2 x Institutional Normal
• Able to provide signed, informed consent.

Exclusion Criteria:

• Patients going on to surgery
• Patients with a serious bleeding disorder that make them inappropriate candidates for NSAID therapy
• Patients with history of significant bleeding related to peptic ulcer disease
• Patients on standing doses of NSAIDS or platelet function inhibitors
• Patients on standing doses of anti-coagulants

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Plavix and Aspirin; Patients will receive a 300 mg loading dose of Plavix on day 1, followed by 75 mg/day, and aspirin 81 mg per day starting day 1. Treatment will be continued until the treating physician elects to resume systemic therapy for the treatment of breast cancer or until unacceptable toxicity is observed. A pill diary will be collected monthly to monitor patients' compliance with the medication regimen.	Drug: Aspirin; Other Names: acetylsalicylic acid; Drug: Plavix; Other Names: Clopidogrel Bisulfate
No Intervention: Observation only; Observation by treating physician

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Platelet Inhibition of Circulating Tumor Cells (CTCs) Measured by the Number of Patients With Detectable CTCs	Measured by number of patients who have detectable circulating tumor cells	Week 4
Safety and Tolerability of Aspirin and Plavix Measured by the Number of Patients Who Discontinue the Study Drug	Measured by number of patients who discontinue administration of study drug because of toxicity and the incidence categorized by type.	Maximum of 6 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Percentage of Patients With a Given Absolute Number of Circulating Tumor Cells (Broken Into Categories) Plotted Against Time	Percent of patients with a given number/range of CTCs ( 0, 1-5 >+ 5) vs. time baseline 2-weeks and 1 month for plavix & Aspirin arm and observation only	Baseline, 2 weeks and 1 month
Mean Aspirin-Mediated Platelet Inhibition vs. Time Plotted for Plavix and Aspirin and Observation Groups	Mean platelet inhibition vs. time plotted for Plavix & Aspirin Arm and Observation group. Citrated whole blood is added to a test carriage containing fibrinogen-coated beads and a platelet activator (arachidonic acid to synthesize thromboxane A2). Using a turbidimetric-based optical detection system, aggregation of activated platelets to fibrinogen-coated beads increase light transmittance which is reported in Aspirin Reaction Units (ARU).	Baseline, 2 weeks and 1 month
Clopidogrel-Mediated Percent of Platelet Inhibition vs. Time Plotted for Aspirin and Plavix and Observation Groups	Mean Clopidogrel-Mediated platelet inhibition (% inhibition) vs. time for Aspirin and Plavix and Observation groups	Baseline, 2 weeks and 1 month
Progression Free Survival		Maximum of 6 months

Collaborators and Investigators

• Sponsor: Washington University School of Medicine
• Collaborators: Barnes-Jewish Hospital
• Investigators: Principal Investigator: Katherine N Weilbaecher, M.D., Washington University School of Medicine

Publications and helpful links

Helpful Links

• Alvin J. Siteman Cancer Center at Barnes-Jewish Hospital and Washington University School of Medicine

Study record dates

Study Major Dates

• Study Start: January 1, 2006
• Primary Completion (Actual): September 1, 2009
• Study Completion (Actual): September 1, 2009

Study Registration Dates

• First Submitted: December 6, 2005
• First Submitted That Met QC Criteria: December 6, 2005
• First Posted (Estimate): December 7, 2005

Study Record Updates

• Last Update Posted (Actual): March 15, 2017
• Last Update Submitted That Met QC Criteria: January 24, 2017
• Last Verified: January 1, 2017

More Information

Terms related to this study

• Keywords: Breast Cancer; Metastatic; Platelet
• Additional Relevant MeSH Terms: Skin Diseases; Neoplasms; Neoplasms by Site; Breast Diseases; Breast Neoplasms; Physiological Effects of Drugs; Neurotransmitter Agents; Molecular Mechanisms of Pharmacological Action; Peripheral Nervous System Agents; Enzyme Inhibitors; Analgesics; Sensory System Agents; Anti-Inflammatory Agents, Non-Steroidal; Analgesics, Non-Narcotic; Anti-Inflammatory Agents; Antirheumatic Agents; Fibrinolytic Agents; Fibrin Modulating Agents; Platelet Aggregation Inhibitors; Cyclooxygenase Inhibitors; Antipyretics; Purinergic P2Y Receptor Antagonists; Purinergic P2 Receptor Antagonists; Purinergic Antagonists; Purinergic Agents; Aspirin; Clopidogrel
• Other Study ID Numbers: 05-0427 / 201107340