A tire which is intended to bear heavy loads and the endurance of which is improved. The tire contains, in the bead region, at least one internal annular insert, the said insert having a rubber composition containing a polyisoprene elastomer, between 45 phr and 60 phr of a reinforcing filler containing from 43 to 55 phr of a reinforcing inorganic filler with a BET specific surface of between 155 and 185 m2/g, and a coupling agent for bonding the reinforcing inorganic filler to the elastomer.