Addition of the vascular-targeted bevacizumab to gemcitabine-docetaxel in patients with chemotherapy-naive metastatic uterine leiomyosarcoma did not improve progression-free survival, overall survival, overall response rate, or response duration, according to a report published online Feb. 23 in the Journal of Clinical Oncology.
The phase III trial found similar outcomes between the 54 patients who took gemcitabine-docetaxel plus placebo and the 53 women who took gemcitabine-docetaxel plus bevacizumab. Progression-free survival was 6.2 months (95% CI, 2.9 to 9.9) vs. 4.2 months (3.1 to 8.4) for gemcitabine-docetaxel plus placebo vs. gemcitabine-docetaxel plus bevacizumab, respectively; the proportion of patients progression free after 12 months was 26.4% vs. 25%, respectively; and the proportion of patients alive after 12 months was 74.7% and 71%, respectively. Safety profiles were similar for the two groups, reported Dr. Martee L. Hensley and associates (J. Clin. Oncol. 2015 Feb. 23 [doi:10.1200/JCO.2014.58.3781]).
Notable in this study was that docetaxel was used at a lower dose, 75 mg/m2, than in previous phase II studies of docetaxel-gemcitabine fixed-dose combinations that used docetaxel at 100 mg/m2. These results show similar overall response rates and response durations for the docetaxel-gemcitabine plus placebo arm and suggest that the lower dose will likely yield similar outcomes with less toxicity.
Few chemotherapy agents have shown activity against metastatic uterine leiomyosarcoma (mLMS). “The failure of bevacizumab to improve any clinical outcome in uLMS raises the question of whether there is any role for antivascular-directed therapy in this disease. Phase II single-agent studies of vascular-targeted agents have mostly yielded negative results,” wrote Dr. Hensley of Memorial Sloan-Kettering Cancer Center and Weill Cornell Medical College, New York, and associates.