Alaunos Therapeutics' indibulin breast cancer trial terminated after Phase 1 only

A Phase I/II trial testing a novel dosing schedule of indibulin in metastatic breast cancer has been marked as terminated, according to its ClinicalTrials.gov record (NCT01113970). The study, sponsored by Alaunos Therapeutics with Memorial Sloan Kettering Cancer Center as a collaborator, was stopped due to a sponsor business decision that closed enrollment after the Phase 1 dose escalation, before a maximum tolerated dose was reached¹. The Phase 2 portion of the trial was not conducted.¹

The trial began on April 6, 2010, with a primary completion date of September 3, 2012, and study completion on May 21, 2013¹. The design called for up to 20 patients in the Phase I portion and up to 45 patients in Phase II¹, but actual enrollment reached 35 participants¹.

The trial enrolled patients with measurable or non-measurable, metastatic or unresectable, locally advanced breast cancer who may have received any number of prior therapies¹. Treatment involved indibulin, also known as ZIO-301 or Zybulin, given orally once a day for 5 days followed by a 9 day rest¹.

The Phase I objective was determining the maximum tolerated dose using a standard 3+3 dose escalation scheme¹, while the planned Phase II primary endpoint was the proportion of patients progression free at 4 months when treated with indibulin at the MTD established in Phase I¹. Because the MTD was never established, this endpoint was not pursued.

The study ran at four sites in the United States: Memorial Sloan-Kettering Cancer Center in New York, The West Clinic in Memphis, Evergreen Hematology Oncology in Spokane, and Northwest Cancer Specialists in Vancouver, Washington¹. The record's last update was posted October 2, 2026.