UNASSIGNED: 140 Background: Eribulin mesylate, a nontaxane microtubule dynamics inhibitor, has demonstrated an overall survival benefit relative to other commonly used agents in @entity1 (pts) with at least 2 prior MBC cytotoxic therapies. Primary data presented from 2 phase 2 trials, Study 206 (eribulin in @entity1722 - @entity0 pts) and Study 208 (combination eribulin + trastuzumab [TRAS] in @entity1722 + @entity0 pts), showed clinical activity and acceptable tolerability profiles as first-line cytotoxic therapy (tx). Here we present prespecified efficacy data for both trials based on prior @entity5948 (A) and @entity3907 (T) use. METHODS: In both studies, pts received eribulin mesylate 1.4 mg/m(2) IV on days 1 and 8 of each 21-day cycle. Pts in Study 208 ( @entity1722 +) also received initial TRAS (8 mg/kg IV/Day 1), followed by 6 mg/kg/day 1 of each subsequent cycle. Objective response rate (ORR), progression-free survival (PFS), and tolerability were assessed. RESULTS: In Study 206 (N=56), 48% and 46% received prior A and T, and in Study 208 (N=52), 21% and 44% received prior A and T, respectively. ORR, the primary endpoint, was similar in pts, regardless of prior A or T, except in pts w/o prior T in Study 208 whose ORR trended higher (table). Clinical benefit rate (CBR), PFS, and duration of response (DOR) were either similar or trended higher in pts w/o prior A or T. PFS was higher in @entity1722 + @entity0 @entity1 receiving @entity69287 + TRAS who had not received prior A or T compared with those who had. Grade (G) 3-5 adverse event rates were similar or lower in pts who had not received prior A or T. CONCLUSIONS: As first-line therapy, eribulin in @entity1722 - @entity0 pts and eribulin + TRAS in @entity1722 + @entity0 pts were effective and well tolerated, regardless of prior A or T tx. However, in @entity1722 + @entity0 pts receiving eribulin + TRAS, the lack of prior A or T tx may be a lead to longer median PFS. CLINICAL TRIAL INFORMATION: NCT01268150/NCT01269346. [Table: see text].

Clinical effects of prior @entity5948 or @entity3907 use on eribulin as first-line treatment for HER+/- locally recurrent or metastatic @entity0 ( XXXX ): Results from 2 phase 2, multicenter, single-arm studies.

@entity1 :: ('9606', 'Species') :: ['patients'] @entity0 :: ('MESH:D001943', 'Disease') :: ['BC'] @entity5948 :: ('D018943', 'Chemical') :: ['anthracycline'] @entity3907 :: ('MESH:C080625', 'Chemical') :: ['taxane'] @entity69287 :: ('MESH:C490954', 'Chemical') :: ['eribulin'] @entity1722 :: ('2064', 'Gene') :: ['HER2']
@entity0 :: (MESH:D001943,Disease) :: ['BC']
