MT-ND4 and Leber hereditary optic neuropathy: A review of primary endpoints for completed and ongoing phase 2, 2/3, and 3 trials in gene therapy through July 2024 revealed trials across eight indications: biallelic RPE65-associated retinal dystrophy, CEP290-mediated LCA10, USH2A-mediated RP, RPGR-mediated XLRP, RP (unspecified), Stargardt, MT-ND4-mediated LHON, and choroideremia.