Kysse is a hyaluronic acid filler, which places it in categories similar to Juvéderm and other Restylane products. The innovation here is that Kysse uses Galderma's proprietary XpresHAn (aka "expression") Technology. As Melanie Palm, a San Diego-based board-certified dermatologist and clinical investigator in the phase three trials of the new drug, explained to Allure, the new filler changes the way that hyaluronic acid binds inside your lips. "[The hyaluronic acid] is bound to itself, so it stretches, and then goes back to its prior space," she says. "When you're talking, smiling, kissing, it has the ability to integrate into the tissue where it's injected and mold to your tissue. It becomes one with [your lips]."