Multicenter, randomised, open-label, non-comparative phase 2 trial on the efficacy and safety of the combination of bevacizumab and trabectedin with or without carboplatin in women with partially platinum-sensitive recurrent ovarian cancer

Background: Trabectedin, in addition to its antiproliferative effect, can modify the tumour microenvironment and this could be synergistic with bevacizumab. The efficacy and safety of trabectedin and bevacizumab ± carboplatin have never been investigated. Methods: In this phase 2 study, women progressing between 6 and 12 months since their last platinum-based therapy were randomised to Arm BT: bevacizumab, trabectedin every 21 days, or Arm BT+C: bevacizumab, trabectedin and carboplatin every 28 days, from cycles 1 to 6, then trabectedin and bevacizumab as in Arm BT. Primary endpoints were progression-free survival rate (PFS-6) and severe toxicity rate (ST-6) at 6 months, assuming a PFS-6 ≤35% for BT and ≤40% for BT+C as not of therapeutic interest and, for both arms, a ST-6 ≥ 30% as unacceptable. Results: BT+C (21 patients) did not meet the safety criteria for the second stage (ST-6 45%; 95%CI: 23%–69%) but PFS-6 was 85% (95%CI: 62%–97%). BT (50 patients) had 75% PFS-6 (95%CI: 60%–87%) and 16% ST-6 (95%CI 7%–30%). Conclusions: BT compared favourably with other platinum- and non-platinum-based regimens. The combination with carboplatin needs to be assessed further in a re-modulated safer schedule to confirm its apparent strong activity. Clinical Trial Registration: NCT01735071 (Clinicaltrials.gov)