REthinking Clinical Trials



De-escalation of bone drugs (zoledronate infusion every 6 months for 3 years vs 1 zoledronate infusion) for patients with early stage breast cancer.

Principal Investigator(s): Dr. Mark Clemons NCT03664687
Patients with breast cancer are treated with an intravenous medication called zoledronate which helps keeps the bone strong, reduces the risk of fractures and has a small benefit in preventing breast cancer cells from going to the bone. This medication is associated with side effects such as feelings similar to a flu, bone pains and may rarely effect the kidneys and healing of the jaw bone. Previous clinical trials have shown that 7 doses of this medication is as effective as 19. We also know that these medications stay in the body/bone for a number of years even with a single dose. Based on this, we designed a clinical trial to assess whether 1 dose of this medication maybe as effective as 7 doses in which 211 patients have participated. We are currently following these patients.

Sites: Cancer Centre of Southeastern Ontario (Kingston, Juravinski Cancer Centre (Hamilton)) Southlake Regional Health Centre (Newmarket) The Ottawa Hospital William Osler Health Centre (Brampton)

Tags: Early stage Breast Cancer


  • Adjuvant bisphosphonate use in patients with early stage breast cancer: Patient perspectives on treatment acceptability and potential de-escalation. McGee et al, 2021.
  • Adjuvant bisphosphonate use in patients with early stage breast cancer: A physician survey. McGee et al, 2021.


  • Feasibility outcomes of a randomised, multicentre, pilot trial comparing standard 6-monthly dosing of adjuvant zoledronate with a single one-time dose in patients with early stage breast cancer. Awan et al, 2020. PMID: 33425673