Sentence: Cohort 7 ( gemcitabine 600 mg/m/wk and carboplatin 2 AUC ) showed 4 dose limiting toxicities : 2 grade 3 esophagitis ; one grade 3 febrile neutropenia ; and one grade 4 neutropenia .
Drug combination annotation:
[{'class': 'COMB', 'spans': ['gemcitabine', 'carboplatin'], 'is_context_needed': True}]