Valbenazine Tosylate

Valbenazine and its active metabolites bind to vesicular monoamine transporter 2 (VMAT2) and block it. They do this with high selectivity, and they don't bind in any significant way to VMAT1. With VMAT2 blocked, the monoamine neurotransmitters noradrenaline, dopamine and serotonin can't be taken back up and stored in synaptic vesicles, so they are left open to being broken down by cytosolic enzymes. There are then fewer vesicles carrying packaged neurotransmitter ready for release into the synapse, and the presynaptic release of these monoamines falls. Neither valbenazine nor its active metabolite shows significant off-target binding at dopamine, serotonin or adrenaline receptors.