P2X4R, a homotrimericreceptor, is highly expressed on immune cells and neurons, and itssurface expression increases in neuroinflammatory conditions likeneuropathic pain and multiple sclerosis.2 P2X4Rs have been found to be involved also in cancer progressionand agressiveness.3 Despite its importance,there is a limited number of P2X4R antagonists reported in the literature,with few showing high efficacy and/or selectivity. The gene discussed is P2RX4; the disease is multiple sclerosis.