Malaria treatment for friend (5)

I believe the answer is:

china

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'for friend' is the definition.
(cockney rhyming slang, mate is china plate)

I don't understand the rest of the clue.

(Other definitions for china that I've seen before include "Make a chain in the country" , "Ceramic ware" , "service" , "Variety of rose" , "friend or companion" .)

I've seen this clue in The Telegraph.

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