Bevacizumab adds no value to chemotherapy for metastatic urothelial cancer
medwireNews: Adding bevacizumab to gemcitabine plus cisplatin chemotherapy does not improve overall survival (OS) when used as first-line therapy for metastatic urothelial carcinoma, show results of the phase III CALGB 90601 study.
These findings are in contrast to those of single-arm phase II trials, which suggested that addition of bevacizumab to chemotherapy prolonged OS relative to historic controls, and therefore highlight “the importance of confirming phase II results in phase III randomized trials” because “pretreatment prognostic factors can heavily influence outcomes in advanced urothelial carcinoma,” Jonathan Rosenberg (Memorial Sloan Kettering Cancer Center, New York, USA) told delegates at the 2019 ASCO Annual Meeting in Chicago, Illinois, USA.
Rosenberg reported that median OS was 14.5 months among the 252 patients randomly assigned to receive gemcitabine 1000 mg/m2 on days 1 and 8, cisplatin 70 mg/m2 on day 1, and bevacizumab 15 mg/kg on day 1 of each 21-day cycle (maximum six cycles).
This was not significantly different from the 14.3-month median OS time observed among the 254 patients randomly assigned to receive gemcitabine, cisplatin and placebo. All of the patients had locally advanced or metastatic unresectable urothelial carcinoma and had not received chemotherapy for metastatic disease prior to study entry.
Median progression-free survival was 7.7 months in the bevacizumab group and 6.6 months in the placebo group. And although the difference between the two groups was statistically significant, Rosenberg said that the 1.1-month improvement with bevacizumab “is not clinically significant.”
The researchers also found no significant improvements with bevacizumab versus placebo when they analyzed the data by sex, primary tumor site, prior chemotherapy, performance score, and whether or not there were visceral metastases.
The overall response rate was 40.4% in the bevacizumab group and 33.0% in the placebo group, again a nonsignificant difference.
Rosenberg said that the toxicity profile of gemcitabine, cisplatin plus bevacizumab “was similar to historic data,” with 83.5% experiencing a grade 3 or higher adverse event, compared with 80.7% in the placebo group.
Based on these findings, Rosenberg concluded: “Currently the standard of care [in these patients] remains cisplatin-based chemotherapy without the addition of biologic agents.
“Ongoing correlative work may identify subsets of patients who may benefit from anti-angiogenic therapy.”
By Laura Cowen
medwireNews is an independent medical news service provided by Springer Healthcare. © 2019 Springer Healthcare part of the Springer Nature group