Triphenylacetic acid

TPA helps stabilize vilanterol, a long-acting beta-2 agonist (LABA), allowing for a single daily dose, improving its pharmacological properties, and facilitating the creation of a solid, pure drug form suitable for inhalation. Triphenylacetic acid (TPA) is used to form the trifenatate salt of the drug vilanterol, creating Vilanterol Trifenatate, a crucial component in medications for COPD and asthma, like Breo Ellipta (with fluticasone furoate) and Anoro Ellipta (with umeclidinium).