Culmination of attempt to pursue secretary brought about by drugs (6)
I believe the answer is:
apogee
'culmination' is the definition.
(synonyms)
'secretary brought about by drugs' is the wordplay.
'secretary' becomes 'pa' (I've seen this in other clues).
'brought about' is a reversal indicator.
'by drugs' becomes 'ogee' (I can't justify this - if you can you should give a lot more credence to this answer).
'pa' written backwards gives 'ap'.
'ap'+'ogee'='APOGEE'
'of attempt to pursue' acts as a link.
This may not be correct. Some or all of it may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for apogee that I've seen before include "Culmination, climax" , "Point at which a satellite is furthest from the Earth" , "Outermost orbital point" , "Culminating point or pinnacle" , "Point in the orbit of the moon that's furthest from the earth" .)