Expanding Options

Session: Randomized phase II trial of weekly ixabepilone with or without biweekly bevacizumab for platinum-resistant or refractory ovarian, fallopian tube, primary peritoneal cancer (NCT3093155)

Presenter: Dana M. Roque, MD, Greenebaum Comprehensive Cancer Center, University of Maryland Medical Center, Baltimore, MD

A new phase II trial may hold promise for heavily pretreated, platinum resistant or refractory ovarian cancer patients

A recent randomized phase II trial introduces Ixabepilone + bevacizumab as a well-tolerated, effective combination for treatment of platinum/taxane resistant ovarian cancer that extends both progression-free and overall survival relative to ixabepilone monotherapy. As an added note to trial results, the authors state that prior receipt of bevacizumab should not preclude use of ixabepilone + bevacizumab.

Dana M. Roque, MD, Greenebaum Comprehensive Cancer Center, University of Maryland Medical Center, Baltimore, MD, delivered these study results as part of SGO 2021’s final presentation: Scientific Plenary VI: Late Breaking Abstracts – Part 2 & Closing Ceremony.

“We had previously reported encouraging activity in the AURELIA trial, our retrospective experience, with ixabepilone ± bevacizumab ovarian and uterine cancers. In the present trial we sought to study the regimens prospective as fashioned after the AURELIA trial,” Dr. Roque explained.

The objective of this multi-center, randomized, phase II study was to assess the activity and safety of ixabepilone (IXA), a microtubule-stabilizing agent that may retain activity in paclitaxel-treated patients, with bevacizumab (BEV) compared to ixabepilone alone in patients with platinum resistant/refractory ovarian, fallopian tube, or primary peritoneal cancer.

An exploratory objective was to examine the role of prior treatment with bevacizumab and tumor expression of class III ß-tubulin (TUBB3) by immunohistochemistry as a predictive biomarker.

On a grander scale, the study authors were intent on expanding action plans for heavily pretreated, platinum resistant or refractory ovarian cancer patients—as these patients, “lack therapeutic options,” Dr. Roque noted,

Participants for this trial were randomly assigned to receive ixabepilone 20 mg/m2 days 1, 8, 15 with (IXA+BEV) or without (IXA) bevacizumab 10 mg/kg days 1, 15 every 28 days, with patients stratified by receipt of prior BEV.

The primary endpoint was progression-free survival. Secondary endpoints included overall survival, safety, and response rates.

Results, as noted in the presentation, are as follows:

  • 78 patients were randomized from March 2017 to July 2020.
  • Among 76 evaluable patients who received IXA+BEV compared to IXA, the objective response rate was 33 percent versus 8 percent, with clinical benefit durable at 6 months in 37 percent and 3 percent.
  • The addition of BEV significantly improved both progression-free survival and overall survival.
  • Both regimens were well tolerated.
  • TUBB3 expression did not predict response in either arm.
  • Subgroup analyses revealed minimal effect of prior BEV on response to IXA+.