If you're curious whether you can save Vlad in Blood of Dawnwalker, chances are you've probably just killed him. Unable to resist your newly-gained vampiric urges, you chomped his neck and drank his blood, and the game didn't give you a choice in the matter.
Well, there is a way Vlad can survive your encounter after he leaves the burning house, towards the end of the prologue. Obviously, this will contain spoilers for this final section of the prologue, so leave 10 seconds ago if you're here by accident.