16304
Synthetic inhibitors of matrix metalloproteinases ( MMPs ) , designed previously , as well as tissue inhibitors of metalloproteinases ( TIMPs ) lack enzyme selectivity , which has been a major obstacle for developing inhibitors into safe and effective MMP - targeted drugs .
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Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
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