This open-label, multicenter, randomized study will consist of a Phase Ib portion: a safety run-in period with 3 ascending doses of eribulin; and a Phase II portion: a randomized 3-arm design. .
Phase Ib-Patients will be recruited into cohorts, into one of two parallel arms evaluating different eribulin dosing schedules (Arm 1: eribulin on Day 1; Arm 2: eribulin on Days 1 and 8), with a minimum of 3 and a maximum of 6 patients per cohort. All patients will receive pemetrexed (500 mg/m2) in combination with eribulin. All patients in a cohort will receive the same dose level of eribulin and there will not be any intra-patient dose escalation.
The dose level of eribulin will be escalated for additional cohorts in each of the two arms unless greater than or equal to 2 dose limiting toxicities (DLTs) are reported at the lower dose level(s) prior to enrollment of the next dose level.
Phase II- Patients will be randomized in a 1:1:1 ratio to receive either eribulin in combination with pemetrexed, in each of two dosing schedules (Arms 1 and 2), or pemetrexed alone (Arm 3). For both the Phase Ib and II portions, 1 cycle of therapy will last 21 days, with an estimated number of 6 cycles. Radiologic examinations including a computed tomography (CT) scan of the chest, abdomen, and pelvis as appropriate (and CT or magnetic resonance imaging [MRI] as appropriate), will be performed during Screening and thereafter every 2 cycles until disease progression.