Safety has been confirmed in a phase II study with isradipine (which, similar to other dihydropyridines, blocks both Cav1.2 and Cav1.3 channels) in preparation for ongoing trials for neuroprotection in patients with Parkinson’s disease (phase III, ClinicalTrials.gov Identifier: NCT02168842) and as adjunct therapy in patients with bipolar depression (phase II, ClinicalTrials.gov Identifier: NCT01784666). This evidence concerns the gene CACNA1C and bipolar disorder.