A pneumatic run-flat tire, the tire comprising at least one carcass reinforcing ply, at least one pair of sidewall wedge inserts, and a belt reinforcing structure, the belt reinforcing structure comprising at least a pair of cross cord belt reinforcing plies, the tire being characterized by at least one pair of elastomeric layers each located radially inward of the at least one carcass reinforcing ply and radially outward of each of the sidewall wedge inserts; the elastomeric layers extending from axially inward of an edge of the belt reinforcing structure to at least a midpoint of a sidewall, the elastomeric layers comprising a rubber composition comprising: 100 parts by weight of natural rubber; from 20 to 30 phr of silica and exclusive of carbon black; and from 0 to 20 phr of polyoctenamer.