Quality of life favors cabazitaxel
Grade 3 or greater adverse events occurred in 42% of patients on cabazitaxel vs. 51% on paclitaxel. Diarrhea, febrile neutropenia, and nausea were the most common grade 3 or greater events in the cabazitaxel arm, whereas grade 3 or greater lung infection and peripheral neuropathy were more common with paclitaxel.
Sensory peripheral neuropathy of any grade occurred in 16% of patients assigned to cabazitaxel, compared with 54% assigned to paclitaxel. The respective rates of alopecia were 27% and 42%.
Over the course of treatment, the mean EuroQuol EQ-5D-5L single index utility score and visual analogue scale score were higher with cabazitaxel arm compared to paclitaxel, suggesting better patient quality of life with cabazitaxel.
In addition, throughout treatment patients in the cabazitaxel arm reported significantly better scores on The Functional Assessment of Cancer Therapy – Breast (FACT-B) breast cancer subscale, Dr. Bahl said.
Second-line may be better
ASCO invited discussant Marleen Kok, MD, PhD, from the Netherlands Cancer Institute in Amsterdam, pointed out that in the phase 2 GENEVIEVE trial comparing the efficacy and safety of cabazitaxel versus weekly paclitaxel as neoadjuvant treatment in patients with triple negative or luminal B/HER2 normal breast cancer the pathologic complete response rate with cabazitaxel was 1.2%, compared with 11% with paclitaxel.
“This GENEVIEVE trial, together with the CONCERT trial, suggests that there is not a big role for cabazitaxel to be used upfront before other taxanes,” she said.
However, in a phase 2 study of cabazitaxel as second-line therapy in patients with HER2-negative metastatic breast cancer who had previously been treated with taxanes, the overall response rate was 23%, “which is still of interest and importance for our patients,” she added.
Dr. Kok did not address quality of life differences between the regimens, however.
In a side note, Dr. Bardia said that “if there were an oral form of paclitaxel, that would certainly be very welcome, in that an oral drug is more convenient for patients, and would require fewer visits to the hospital.”
The CONCERT trial was funded by an investigator-sponsored study grant from Sanofi. Dr. Bahl disclosed honoraria and institutional research funding from Sanofi/Aventis and others, and travel expenses from Bayer and Roche. Dr. Kok disclosed a consulting or advisory role for Bristol Myers Squibb/Medarex, and institutional research funding from that company and others. Dr. Bardia disclosed a consulting or advisory role and research funding to his institution from multiple companies.