I had a tire with a screw impregnation like that one, it didn't leak air, so I just drove it. After a few thousand miles the screw head had worn off and the remaining portion of the screw was flush with the tread. Three years later I replaced it with a new tire as part of a set of four, it never gave me any grief. If you don't want to keep running it, that's fine, but as long as you carry a spare, I say wear it out.