exec sp_rename 'AKUZ.T_VACCINATION_IMMUNITY.TitrAntitel', 'TitrAntitelOld', 'COLUMN'
go

ALTER TABLE [AKUZ].[T_VACCINATION_IMMUNITY] ADD [TitrAntitel] int NULL
GO

update AKUZ.T_VACCINATION_IMMUNITY
set TitrAntitel = cast(substring(cast(TitrAntitelOld as varchar(5)), 3, 3) as int)

exec dbo.sp_AlterDropColumn '[AKUZ].[T_VACCINATION_IMMUNITY]' , 'TitrAntitelOld', 0
GO