Sentence: Raloxifene , an anti-osteoporotic drug , is recently approved for prevention of breast cancer in postmenopausal women and thus the drug may be employed to combat the bony adverse effects of letrozole , another anticancer drug .
Drug combination annotation:
[{'class': 'POS', 'spans': ['Raloxifene', 'letrozole'], 'is_context_needed': True}]