– P2X3 antagonist 34, a potent, selective, and orally active antagonist, targets the P2X3 homotrimeric receptor, exhibiting IC50s of 25 nM, 92 nM, and 126 nM for human, rat, and guinea pig P2X3 receptors respectively. It shows reduced activity against P2X2/3 heterotrimeric receptors across human, rat, and guinea pig models. Notably, this compound demonstrates a significant anti-tussive effect without altering taste[1].