LBA58BAROCCO: A randomized phase II study of weekly paclitaxel vs cediranib-olaparib combination given with continuous or intermittent schedule in patients with recurrent platinum resistant ovarian cancer (PROC)

Abstract Background Hypoxia induced by antiangiogenic agents could cause a functional impairment of homologous recombination, thus sensitizing wild-type (wt) BRCA tumor cells to PARP inhibition. In a phase II study the combination of cediranib-olaparib increased progression free survival (PFS) in women with recurrent platinum sensitive OC with respect to olaparib. Methods 123 patients were allocated in a 1:1:1 ratio to receive: 80 mg/m2 weekly paclitaxel up to 24 weeks (control), olaparib 600 mg tablet (300 mg twice daily) together with 20 mg cediranib daily (continuous schedule) or 20 mg cediranib given 5 days/week (intermittent schedule) until progression. PFS comparison between experimental schedules and the control arm (alpha one-sided 5%; power 80% to detect a HR of 0.5) was the primary objective. Results Median platinum-free interval was 1.8 mos, 59% of patients were pretreated with >3 chemotherapy lines. Median PFS for paclitaxel, the continuous, and the intermittent schedules were 3.1, 5.7, and 3.8 mos. Estimated HR for PFS in continuous arm vs control was 0.76 (90% CI: 0.49-1.17), p = 0.28 by log-rank test. HR for PFS in intermittent arm vs. control was 1.08 (90% CI: 0.71-1.64), p = 0.76 by log-rank test. In the subgroup gBRCA wt (n = 109) the median PFS for paclitaxel, the continuous, and the intermittent schedules were 2.1, 5.8 and 3.8 mos and HR for PFS in continuous arm vs control was 0.63 (95% CI: 0.36 to 1.10; p = 0.10). The toxicity profile of the study arms was as expected and similar between experimental arms. 11%, 18%, and 7% in control, continuous and intermittent arm discontinued treatment for adverse events. Five serious adverse drug reactions occurred and two of these were fatal: one in the control and one in the continuous arm. Conclusions The combination of cediranib and olaparib is effective in heavily pretreated PROC patients with the advantage of an oral administration and good tolerability. The continuous schedule of cediranib-olaparib showed a promising trend towards improved PFS in comparison with weekly paclitaxel particularly in the BRCA wt population. Clinical trial identification IRFMN-OVA-7289, EudraCT: 2016-003964-38, NCT03314740. Legal entity responsible for the study Istituto di Ricerche Farmacologiche Mario Negri IRCCS. Funding AstraZeneca. Disclosure N. Colombo: Honoraria (self), Advisory / Consultancy: Roche/Genentech; Honoraria (self), Advisory / Consultancy: PharmaMar; Honoraria (self), Advisory / Consultancy: AstraZeneca; Honoraria (self), Advisory / Consultancy: Tesaro; Advisory / Consultancy: Clovis Oncology; Advisory / Consultancy: Pfizer; Advisory / Consultancy: MSD Oncology; Advisory / Consultancy: BioCad; Advisory / Consultancy: Takeda. G. Tognon: Advisory / Consultancy: Amgen; Speaker Bureau / Expert testimony, Research grant / Funding (institution): Roche; Speaker Bureau / Expert testimony, Research grant / Funding (institution): AstraZeneca; Speaker Bureau / Expert testimony: Tesaro. M. Ratti: Travel / Accommodation / Expenses: Tesaro Bio. All other authors have declared no conflicts of interest.