A phase I study of everolimus and docetaxel in patients with castration-resistant prostate cancer. Academic Article uri icon

Overview

abstract

  • BACKGROUND: The PTEN tumor suppressor is frequently lost in CRPC, with activation of Akt-mTOR signaling, driving growth. We conducted a phase I trial of the mTOR inhibitor, everolimus, and docetaxel in CRPC. PATIENTS AND METHODS: Eligible patients had progressive, metastatic, chemotherapy-naive CRPC. Patients received everolimus 10 mg daily for 2 weeks and underwent a restaging FDG-PET/computed tomography scan. Patient cohorts were subsequently treated at 3 dose levels of everolimus with docetaxel: 5 mg to 60 mg/m(2), 10 mg to 60 mg/m(2), and 10 mg to 70 mg/m(2). The primary end point was the safety and tolerability of combination therapy. RESULTS: Accrual was 4 patients at level 1, 3 patients at level 2, and 8 patients at level 3. Common toxicities were hematologic and fatigue. Serum concentrations of everolimus when administered with docetaxel were 1.5 to 14.8 ng/mL in patients receiving 5 mg everolimus and 4.5 to 55.4 ng/mL in patients receiving 10 mg everolimus. Four patients had partial metabolic response (PMR) using FDG-PET, 12 had stable metabolic disease, and 2 had progressive metabolic disease after a 2-week treatment with everolimus alone. Five of 12 evaluable patients experienced a prostate-specific antigen (PSA) reduction ≥ 50% during treatment with everolimus together with docetaxel. All 4 patients with a PMR according to PET imaging experienced a PSA reduction in response to everolimus with docetaxel, and 3 of 4 had PSA declines ≥ 50%. CONCLUSION: Everolimus 10 mg daily and docetaxel 60 mg/m(2) was safe in CRPC patients and these were the recommended doses in combination. FDG-PET response might serve as a biomarker for target inhibition by mTOR inhibitors.

publication date

  • October 22, 2014

Research

keywords

  • Antineoplastic Agents
  • Antineoplastic Combined Chemotherapy Protocols
  • Everolimus
  • Fluorodeoxyglucose F18
  • Prostatic Neoplasms, Castration-Resistant
  • Taxoids

Identity

PubMed Central ID

  • PMC4418946

Scopus Document Identifier

  • 84924580967

Digital Object Identifier (DOI)

  • 10.1016/j.clgc.2014.08.007

PubMed ID

  • 25450031

Additional Document Info

volume

  • 13

issue

  • 2