25239225
BACKGROUND	The purpose of this study was to assess the efficacy and safety of trabectedin for advanced breast cancer .
METHODS	In an open-label , phase II , multicenter study , women with advanced breast cancer previously treated with 2 lines of chemotherapy for advanced disease , including both anthracyclines and taxanes , were randomized ( 1:1 ) to 3-hour infusions of trabectedin 1.3 mg/m ( 2 ) once every 3 weeks ( 1/3 treatment arm ) or 0.58 mg/m ( 2 ) every week for 3 of 4 weeks ( 3/4 treatment arm ) .
METHODS	The primary end point was objective response .
METHODS	Secondary end points included time to progression ( TTP ) , progression-free survival ( PFS ) , and overall survival ( OS ) .
RESULTS	Fifty-two women ( median age , 50 years ; median chemotherapy agents , 4 ) were enrolled .
RESULTS	Relative trabectedin dose intensities were 81 % and 76 % in the 1/3 and 3/4 treatment arms , respectively .
RESULTS	Objective response rates were 12 % ( 3 of 25 ) and 4 % ( 1 of 27 ) , respectively .
RESULTS	Stable disease was observed in 14 ( 56 % ) and 11 ( 41 % ) patients in the 1/3 and 3/4 treatment arms , respectively , with median durations of 3.5 and 3.7 months .
RESULTS	Median TTP and PFS were higher in the 1/3 treatment arm ( 3.1 months each ) than in the 3/4 treatment arm ( 2.0 months each ) .
RESULTS	At a median follow-up of 7 months in both treatment arms , median OS was not reached in the 1/3 treatment arm and was 9.4 months in the 3/4 treatment arm .
RESULTS	The most frequent drug-related adverse events in the 1/3 and 3/4 treatment arms , respectively , were alanine aminotransferase ( ALT ) level increases ( 68 % vs. 63 % ) , nausea ( 56 % vs. 59 % ) , and asthenia ( 56 % vs. 48 % ) .
RESULTS	Neutropenia and increases in ALT levels were the most frequent grade 3/4 events .
RESULTS	Both types of events were usually transient and reversible .
CONCLUSIONS	In the population studied , trabectedin showed a manageable safety profile for both regimens analyzed .
CONCLUSIONS	There were higher objective response rates and a longer PFS in the 1/3 treatment arm compared with the 3/4 treatment arm .

