Literary town always hosting fine comic play (3,5)
I believe the answer is:
hay fever
'comic play' is the definition.
(play by Noel Coward)
'literary town always hosting fine' is the wordplay.
'literary town' becomes 'hay' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'always' becomes 'ever' (synonyms).
'hosting' is an insertion indicator (inserted letters are welcomed in or hosted).
'fine' becomes 'f' (abbreviation).
'hay'+'ever'='hayever'
'hayever' enclosing 'f' is 'HAY-FEVER'.
Can you help me to learn more?
(Other definitions for hay fever that I've seen before include "Irritation caused by pollen" , "Pollinosis" , "summer glums?" , "Coward created this" , "Allergy caused by pollen, dust etc" .)