Bortezomib (VELCADE) in metastatic breast cancer: pharmacodynamics, biological effects, and prediction of clinical benefits

Ann Oncol. 2006 May;17(5):813-7. doi: 10.1093/annonc/mdj131. Epub 2006 Jan 10.


Background: Bortezomib (VELCADE) is a potent inhibitor of the 26S proteasome with broad antitumor activity. We performed a phase II study of bortezomib to evaluate its clinical effects in patients with metastatic breast cancer.

Patients and methods: Twelve patients with metastatic breast cancer were treated with bortezomib (VELCADE) at a dosage of 1.5 mg/m(2) administered biweekly for 2 weeks with 1 week of rest in a 21-day cycle. The primary objective was clinical response rate. Toxicity and pharmacodynamics data were also obtained.

Results: No objective responses were observed. One patient had stable disease, and 11 others experienced disease progression. The median survival time was 4.3 months (range, 0.9-37 months). The most common grade 3 or 4 toxicities included fatigue (58%; n = 7) and skin rash (33%; n = 4). The mean inhibition of specific chymotryptic activity was 53.1% (+/- 13.33%). A statistically significant reduction in the plasma interleukin-6 level was seen (P = 0.0354).

Conclusion: Bortezomib was well tolerated but showed limited clinical activity against metastatic breast cancer when used as a single agent. The future development of this agent for the treatment of breast cancer should be guided by in vivo models that optimize activity in combination with other antitumor agents.

Publication types

  • Clinical Trial, Phase II

MeSH terms

  • Adult
  • Aged
  • Bone Neoplasms / drug therapy*
  • Bone Neoplasms / secondary
  • Boronic Acids / pharmacology
  • Boronic Acids / therapeutic use*
  • Bortezomib
  • Breast Neoplasms / drug therapy*
  • Breast Neoplasms / pathology
  • Disease Progression
  • Disease-Free Survival
  • Female
  • Humans
  • Male
  • Maximum Tolerated Dose
  • Middle Aged
  • Pleural Neoplasms / drug therapy*
  • Pleural Neoplasms / secondary
  • Protease Inhibitors / pharmacology
  • Protease Inhibitors / therapeutic use*
  • Pyrazines / pharmacology
  • Pyrazines / therapeutic use*
  • Receptors, Estrogen / metabolism
  • Receptors, Progesterone / metabolism
  • Soft Tissue Neoplasms / drug therapy*
  • Soft Tissue Neoplasms / secondary
  • Survival Rate
  • Treatment Outcome


  • Boronic Acids
  • Protease Inhibitors
  • Pyrazines
  • Receptors, Estrogen
  • Receptors, Progesterone
  • Bortezomib