16587
The decrease in serum TB12 during treatment was greater with increasing treatment duration in metformin - treated ( p < 0 . 001 ) , but not in insulin - treated women .
 Chemical: metformin
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
 Chemical: metformin