Peptide Graded

Balixafortide

Does Balixafortide work?

Partly: some human trials, with gaps: a 56-patient early study looked hopeful, then a 432-patient trial found no benefit.

BSome human evidenceIn clinical trialsas of 2026-10-27

A 56-patient single-arm phase 1 trial with eribulin in metastatic breast cancer suggested a higher response rate than eribulin alone, but the randomized phase 3 FORTRESS trial in 432 patients found no improvement in response rate, progression-free survival or overall survival. A negative randomized trial is grade B evidence against the claimed benefit. 123

A phase 1 trial with a single arm was published in The Lancet Oncology in 2018. Researchers gave balixafortide with eribulin to 56 women. All had HER2-negative metastatic breast cancer and had already had heavy treatment. Of 54 patients who could be evaluated, 16 had partial responses (30%). The investigators saw this as promising against past response rates for eribulin alone. There was no control group. 1

FORTRESS was the phase 3 trial. It was randomized and open-label. It enrolled 432 patients. They got eribulin alone or eribulin plus balixafortide. Response rate and progression-free survival were the two main measures. In June 2021 the main analysis looked at response rate in patients on third-line treatment or later. It found 13.0% with the combination and 13.7% with eribulin alone. The clinical benefit rate was slightly higher without balixafortide (19.6% versus 16.7%). Polyphor reported in August 2021 that progression-free survival had not improved either. An interim analysis of overall survival showed no difference. The study was closed. 23

Evidence checklist

  • Randomised controlled trial FORTRESS phase 3, eribulin with or without it
  • Human study over 100 people FORTRESS 432 patients
  • More than one research group Sponsor trials only; one program
  • Clinical outcomes, not surrogate markers Response, progression-free and overall survival
  • Human safety data beyond case reports Phase 1 and phase 3 adverse event data

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More on Balixafortide

Citations

  1. Pernas 2018, Lancet Oncology: balixafortide plus eribulin in HER2-negative metastatic breast cancer, phase 1 trial pubmed.ncbi.nlm.nih.gov
  2. Clinical Trials Arena: Polyphor's balixafortide fails phase 3 FORTRESS breast cancer study clinicaltrialsarena.com
  3. OncLive, June 2021: balixafortide plus eribulin fails to improve response rate in the FORTRESS trial onclive.com
  4. ClinicalTrials.gov: NCT06981806, balixafortide with cosibelimab in pancreatic cancer clinicaltrials.gov

Reference information only, not medical advice. Drawn from the Balixafortide article, fact-checked against the cited sources. No dosing anywhere on this site.