Randomized phase III trial of gemcitabine plus docetaxel plus bevacizumab or placebo as first-line treatment for metastatic uterine leiomyosarcoma: an NRG Oncology/Gynecologic Oncology Group study

Abstract

Purpose: Fixed-dose rate gemcitabine plus docetaxel achieves objective response in 35% of patients with uterine leiomyosarcoma (uLMS). This study aimed to determine whether the addition of bevacizumab to gemcitabine-docetaxel increases progression-free survival (PFS) in uLMS.

Patients and methods: In this phase III, double-blind, placebo-controlled trial, patients with chemotherapy-naive, metastatic, unresectable uLMS were randomly assigned to gemcitabine-docetaxel plus bevacizumab or gemcitabine-docetaxel plus placebo. PFS, overall survival (OS), and objective response rates (ORRs) were compared to determine superiority. Target accrual was 130 patients to detect an increase in median PFS from 4 months (gemcitabine-docetaxel plus placebo) to 6.7 months (gemcitabine-docetaxel plus bevacizumab). Treatment effects on PFS and OS were described by hazard ratios (HRs), median times to event, and 95% CIs.

Results: In all, 107 patients were accrued: gemcitabine-docetaxel plus placebo (n = 54) and gemcitabine-docetaxel plus bevacizumab (n = 53). Accrual was stopped early for futility. No statistically significant differences in grade 3 to 4 toxicities were observed. Median PFS was 6.2 months for gemcitabine-docetaxel plus placebo versus 4.2 months for gemcitabine-docetaxel plus bevacizumab (HR, 1.12; P = .58). Median OS was 26.9 months for gemcitabine-docetaxel plus placebo and 23.3 months for gemcitabine-docetaxel plus bevacizumab (HR, 1.07; P = .81). Objective responses were observed in 17 (31.5%) of 54 patients randomly assigned to gemcitabine-docetaxel plus placebo and 19 (35.8%) of 53 patients randomly assigned to gemcitabine-docetaxel plus bevacizumab. Mean duration of response was 8.6 months for gemcitabine-docetaxel plus placebo versus 8.8 months for gemcitabine-docetaxel plus bevacizumab.

Conclusion: The addition of bevacizumab to gemcitabine-docetaxel for first-line treatment of metastatic uLMS failed to improve PFS, OS, or ORR. Gemcitabine-docetaxel remains a standard first-line treatment for uLMS.

Trial registration: ClinicalTrials.gov NCT01012297.

Conflict of interest statement

Authors' disclosures of potential conflicts of interest are found in the article online at www.jco.org. Author contributions are found at the end of this article.

© 2015 by American Society of Clinical Oncology.

Figures

Fig 1.

CONSORT diagram. Patients who received none of the protocol therapy were excluded from the assessment of toxicity. The analysis was done on an intent-to-treat basis. Some patients were deemed to have inadequate pathology, but these patients were not excluded from any of the reported results. ORR, overall response rate; OS, overall survival; PFS, progression-free survival.

Fig 2.

Progression-free survival among patients assigned to gemcitabine-docetaxel (GD) plus placebo (Plac; n = 54) or GD plus bevacizumab (Bev; n = 53). Cens, censored.

Fig 3.

Overall survival among patients assigned to gemcitabine-docetaxel (GD) plus placebo (Plac; n = 54) or GD plus bevacizumab (Bev; n = 53). Cens, censored.