CPT is a synthetic chemical developed as a selective inhibitor against CaV1.3 channels for therapy in Parkinson’s disease (Kang et al., 2012, 2013), which is now identified as a selective negative allosteric modulator of Cav1.3 by binding to dihydropyridine (DHP) binding pocket on CaV1.3 subunits (Cooper et al., 2020). This evidence concerns the gene CACNA1D and Parkinson disease.