Sentence: A Phase II Randomized Study of Neoadjuvant Letrozole Plus Alpelisib for Hormone Receptor-Positive , Human Epidermal Growth Factor Receptor 2-Negative Breast Cancer ( NEO-ORB ) .
Drug combination annotation:
[{'class': 'NEG', 'spans': ['Letrozole', 'Alpelisib'], 'is_context_needed': True}]