GRM3 and Parkinson disease: For instance, POMAGLUMETAD METHIONIL (GRM3) is a metabotropic glutamate receptor 3 agonist that has been tested for SZ (https://clinicaltrials.gov/ct2/show/NCT01452919) and TOPIRAMATE (GRIK1) has been used for BD (NCT00240721, NCT00035230, NCT00237289), cognitive impairment (NCT02884050), and PD (NCT00296959).