Oral metronomic chemotherapy with vinorelbine, cyclophosphamide, and capecitabine (VEX) appears more effective than paclitaxel monotherapy for patients with estrogen receptor (ER)-positive, HER2-negative metastatic breast cancer, according to results of the METEORA-II trial.
In this phase 2 trial, VEX significantly improved time to treatment failure (TTF) and progression-free survival (PFS). However, the rate of targeted grade 3 or higher adverse events (AEs) was greater with VEX.
These results were presented at ESMO Congress 2022 by Elisabetta Munzone, MD, of Istituto Europeo di Oncologia in Milan, Italy.
The METEORA-II trial (ClinicalTrials.gov Identifier: NCT02954055) randomly assigned 133 patients to receive VEX (n=70) or paclitaxel (n=63) in 4-week cycles. Patients were treated until disease progression or lack of tolerability.
In the VEX arm, vinorelbine was given at 40 mg on days 1, 3, and 5 every week; cyclophosphamide was given at 50 mg daily; and capecitabine was given at 500 mg 3 times per day. Paclitaxel was given at 90 mg/m2 on days 1, 8, and 15 of each cycle.
The median TTF was 8.3 months in the VEX arm and 5.7 months in the paclitaxel arm (hazard ratio [HR], 0.61; 95% CI, 0.42-0.88; P=.008). The 12-month TTF rate was 34.3% with VEX and 8.6% with paclitaxel.
The median PFS was 11.1 months in the VEX arm and 6.9 months in the paclitaxel arm (HR, 0.67; 95% CI, 0.46-0.96). The 12-month PFS rate was 43.5% with VEX and 21.9% with paclitaxel.
There was no significant difference in overall survival (OS). The median OS was 29.5 months in the VEX arm and 33.7 months in the paclitaxel arm (HR, 0.98; 95% CI, 0.59-1.63). The 12-month OS rate was 79.9% with VEX and 79.2% with paclitaxel.
Targeted grade 3 or higher AEs occurred in 42.9% of patients in the VEX arm and 28.6% of patients in the paclitaxel arm. Neutrophil count decrease was the most frequent grade 3/4 AE, occurring in 28.6% of patients in the VEX arm and 14.3% of those in the paclitaxel arm. Grade 5 AEs occurred in 2.9% of patients in the VEX arm and 3.2% of those in the paclitaxel arm.
Disclosures: This research was supported by ETOP IBCSG Partners Foundation. Some study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of disclosures.
Munzone E, Regan MM, Cinieri S, et al. A randomized phase II trial of metronomic oral vinorelbine plus cyclophosphamide and capecitabine (VEX) vs weekly paclitaxel (P) as first- or second-line treatment in patients (pts) with ER+/HER2- metastatic breast cancer (MBC): The METEORA-II trial (IBCSG 54-16). Presented at ESMO 2022; September 9-13, 2022. Abstract 216MO.