Sentence: The combination of rituximab , bendamustine , and cytarabine ( R-BAC ) was highly active in a pilot trial of mantle cell lymphoma , but its use was restricted by high haematological toxicity .
Drug combination annotation:
[{'class': 'POS', 'spans': ['rituximab', 'bendamustine', 'cytarabine'], 'is_context_needed': False}]