New aid in coma — it’s found in proteins (5,4)
I believe the answer is:
amino acid
'it's found in proteins' is the definition.
(compound found in proteins)
'new aid in coma' is the wordplay.
'new' indicates anagramming the letters.
'aid'+'in'+'coma'='aidincoma'
'aidincoma' with letters rearranged gives 'AMINO-ACID'.
(Other definitions for amino acid that I've seen before include "compound for life" , "Chemical" , "Organic compound in proteins" , "source of protein required?" , "Basic protein constituent" .)