Phase II evaluation of eribulin mesylate (E7389, NSC 707389) in patients with metastatic or recurrent squamous cell carcinoma of the head and neck: Southwest Oncology Group trial S0618.

PURPOSE: Eribulin mesylate, an halichondrin B analog, binds to tubulin and microtubules and possesses broad anti-cancer activity. We conducted a multi-institutional Phase II trial to evaluate the response rate of eribulin mesylate in patients with metastatic or recurrent squamous cell carcinoma of the head and neck (SCCHN). EXPERIMENTAL
DESIGN: Forty eligible patients who had not received prior chemotherapy for metastatic or recurrent SCCHN were enrolled with the following characteristics: 29 male, 11 female; median age 61.2 years; Zubrod Performance Status of 0 (48%) and 1 (53%). Thirty-three patients (83%) had metastatic disease. Primary tumor sites included: 38% oropharynx, 30% lip/oral cavity, 15% larynx, 10% hypopharynx, 5% other/unknown and 3% nasopharynx. Patients received eribulin mesylate at 1.4 mg/m² on Days 1 and 8 of an every 21-day cycle.
RESULTS: Common Grade 3 and 4 toxicities included: lymphopenia (15%), leukocytopenia (13%), neutropenia (10%), hyponatremia (5%), fatigue (5%), diarrhea (5%) and dyspnea (5%), with one treatment-related death due to pulmonary hemorrhage. Among 40 assessable patients, two confirmed partial responses were observed, for an estimated confirmed response rate of 5% (95% confidence interval: 1-17%). The estimated median progression-free survival is 3 months (95% confidence interval: 1-3 months) and estimated median overall survival is 7 months (95% confidence interval: 5-10 months).
CONCLUSIONS: Eribulin mesylate given on Days 1 and 8 of a twenty-one day cycle in metastatic or recurrent SCCHN was well tolerated, but did not result in a clinically significant median PFS. Studies of other agents should be considered in this setting.