Unfortunately, there’s no stopping the Tyrant in Resident Evil 2. Once he enters the game, he will pursue the player relentlessly until they progress to a certain point in the story. The player only has three options when faced with this invincible beast: fight, flight, and hiding.
Fighting the Tyrant in Resident Evil 2 is the most direct way to deal with him. Pump enough ammo into the beast, and he’ll momentarily yield.