21155
To date , there have been several phase II and phase III studies that have examined the efficacy of first - line single - agent EGFR TKIs in unselected , clinically selected or molecularly selected populations .
 None
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
 Entities:  
Answer:
 None