- The most frequently reported eribulin-related AEs were asthenia/fatigue (65%), alopecia (60%), neutropenia (60%), nausea (44%), anemia (28%), pyrexia (23%), leucopenia (22%), anorexia (21%), constipation (19%), vomiting (18%), and peripheral neuropathy (5.5%; only grade 3). Grade 4 neutropenia occurred in 32% of patients, and febrile neutropenia occurred in 5.5% of patients. The frequency of all other grade 3/4 AEs was less than 3%. This toxicity profile does not overlap with that of lapatinib.