what type of biting ?is it dog agression/attacking ? if yes best way is to lower down the energy by giving good exercise... a simple trick that i use personally is purchase a green laser torch and let your brute follow it..ensure that he follows the ray point of laser torch and than let him run behind the ray which should be just before the brute.. If he is fully concentrated on the ray, make sure he is tired down by giving him a good run.. He will not run away from you even if he is not leashed.....If you have a big terrace try to practice there with the ray on floor else the brute may jump off following the laser torch ray..Ensure not to panic he is in open and tries to bite strangers ..Keep cool and point the laser torch just in front of him.. He will just forget his surroundings..If he is biting/teething a good chow/smoked bone for his teeth exercise will do