Here are some things that help me with difficult passages:
Obviously, HS practice and slow practice
HT, think about each 1-bar phrase and play
that phrase, which ends on the downbeat over the bar line. Play only the first one--then the second, then play them in sequence--keep doing this until you have the whole passage.
Observe what seems to trip you up, try to analyze why. HT rapid parallel stuff is difficult, partly because the hands are mirror-images and you are playing the opposite thing in each hand when you play in parallel.
Practice hard one day, and get a good night's sleep. Maybe don't practice that hard part the next day. You may find amazing improvement next time you play it!
Think the passage is actually a breeze! Sometimes just getting over a mental block is all you need.

Good luck and have fun!
Teresa