Tolerability and Efficacy of Bevacizumab Monotherapy in Older Patients With Recurrent Ovarian Cancer

Platinum-free Interval May Predict Duration of Maintenance Bevacizumab and Survival in Platinum-sensitive Recurrent Ovarian Cancer

BACKGROUND/AIM

We investigated factors affecting the long-term duration of bevacizumab-based maintenance therapy (BMT) and survival in patients with the first platinum-sensitive recurrence of ovarian cancer (PSR).

PATIENTS AND METHODS

We included patients with the first PSR in two tertiary centers from January 2015 till August 2021. All patients received six cycles of paclitaxel, carboplatin, and bevacizumab followed by BMT. We collected data including age at recurrence, histologic types, the status of BRCA mutation, platinum-free interval (PFI), extent of secondary cytoreductive surgery (SCS), presence of extra-abdominal disease, numbers of recurred lesions, cycles of BMT, progression-free survival (PFS), and cancer-specific survival (CSS). The median cycles of BMT were 13 (range=1-108).

RESULTS

A total 103 patients were included, who consisted of the short-term (<13 cycles; n=49; 47.6%) and long-term users of BMT (≥13 cycles; n=54; 52.4%). High-grade serous carcinoma (HGSC), PFI >12 months, and optimal cytoreduction during SCS were favorable factors for the long-term duration of BMT. Moreover, PFI >12 months and the long-term duration of BMT were factors for improved PFS, and HGSC and PFI >12 months were related to improved CSS.

CONCLUSION

PFI >12 months may be associated with the long-term duration of BMT and improved survival in patients with the first PSR.

Randomised phase II trial of weekly ixabepilone ± biweekly bevacizumab for platinum-resistant or refractory ovarian/fallopian tube/primary peritoneal cancer

BACKGROUND

This multi-center RP2 study assessed activity/safety of ixabepilone + bevacizumab compared to ixabepilone in platinum-resistant/refractory ovarian/fallopian tube/primary peritoneal cancer. Additional objectives were to examine the role of prior bevacizumab and taxanes, and explore class III-ß-tubulin (TUBB3) as a predictive biomarker.

METHODS

Participants were randomised 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. Patients were stratified by prior BEV. The primary endpoint was PFS. OS, safety, and ORR served as secondary endpoints.

RESULTS

Among 76 evaluable patients who received IXA + BEV (n = 39) compared to IXA (n = 37), the ORR was 33% (n = 13) versus 8% (n = 3)(P = 0.004), durable at 6 months in 37% (n = 14) and 3% (n = 1) (P < 0.001). BEV significantly improved PFS (median:5.5 vs 2.2 months, HR = 0.33, 95%CI 0.19-0.55, P < 0.001) and OS (median:10.0 vs 6.0 months, HR = 0.52, 95%CI 0.31-0.87, P = 0.006). Both regimens were well-tolerated. TUBB3 expression did not predict response. Subgroup analyses revealed minimal effect of prior BEV or taxane resistant/refractory status on response to IXA + BEV.

CONCLUSIONS

IXA + BEV is a well-tolerated, effective combination for platinum/taxane-resistant ovarian cancer that extends PFS and likely OS relative to IXA monotherapy. Prior receipt of BEV should not preclude the use of IXA + BEV. TUBB3 is not a predictive biomarker.

CLINICAL TRIAL REGISTRATION

NCT3093155.