Dosing Intervals of Vinorelbine Under Study in HER2-Negative Breast Cancer
Posted: Tuesday, December 21, 2021
Administration of first-line weekly vinorelbine to patients with hormone receptor–positive/HER2-negative advanced breast cancer leads to prolonged survival, although metronomic dosing seems to lead to better patient tolerance. These results were presented by Marina E. Cazzaniga, MD, of Ospedale San Gerardo in Monza, Italy, during the European Society for Medical Oncology (ESMO) Congress 2021 (Abstract 203P) and published in the Annals of Oncology.
“Awaiting the results of other ongoing randomized studies in combination or later lines, weekly single-agent vinorelbine should be preferred over metronomic single-agent vinorelbine in first-line chemotherapy after progression on endocrine therapy in hormone receptor–positive advanced breast cancer patients,” concluded the authors.
This phase II study recruited 163 patients with advanced breast cancer who had either not received prior therapy or had been pretreated with endocrine therapy and were no longer candidates for further endocrine therapy. Patients were randomly assigned to receive either metronomic vinorelbine at a dose of 50 mg three times a week orally or a weekly dose of 60 mg/m2 orally for cycle 1, increasing to 80 mg/m2 orally for subsequent cycles.
The disease control rate was 63.4% among the metronomic-dosing group and 72.8% in the weekly-dosing group. The median progression-free survival among the groups given metronomic and weekly dosing were 4.0 and 5.6 months, respectively. Median overall survival was 22.3 months in the group receiving metronomic vinorelbine and 26.7 months in the group receiving weekly treatment.
Grade 3 or higher adverse events were noted among 31% of patients in the metronomic-dosing group, whereas 60% of patients in the weekly-dosing group experienced adverse events, including neutropenia (24% vs. 51%, respectively) and febrile neutropenia (0% vs. 2.5%). There was similarly less gastrointestinal toxicity with metronomic dosing (46%) compared with weekly dosing (73%). There were four total toxic deaths reported, two in each group; two deaths were from sepsis, one was from enterocolitis, and one was from cardiac failure.
Disclosure: For a full list of authors’ disclosures, visit oncologypro.esmo.org.