HYR-PB21-LA, a potential extended-release bupivacaine formulation, produces long-lasting local anesthesia in rats and guinea pigs

The results demonstrated that the HYR-PB21-LA produced longer local anesthesia effect than current clinical preparations of bupivacaine in two animal models. These findings raise the potential clinical value of HYR-PB21-LA as a long-lasting local anesthesia for controlling postsurgical pain in humans.