The affected creature suffers from a continuous '_confusion_':spells/players-handbook-v35--6/confusion--2538/ effect, as the spell.
Remove curse does not remove insanity. '_Greater restoration_':spells/players-handbook-v35--6/restoration-greater--2431/, '_heal_':spells/players-handbook-v35--6/heal--2398/, '_limited wish_':spells/players-handbook-v35--6/limited-wish--2899/, '_miracle_':spells/players-handbook-v35--6/miracle--2633/, or '_wish_':spells/players-handbook-v35--6/wish--2902/ can restore the creature.