Allergan has announced the acquisition of all the assets of RetroSense Therapeutics, a private, clinical-stage biotechnology company specializing in innovative gene therapy approaches to restore vision. RetroSense's lead development program, RST-001, is a novel gene therapy for the potential treatment of retinitis pigmentosa (RP). Under the terms of the agreement, Allergan has paid RetroSense a $60 million upfront payment, and has agreed to milestone payments related to RST-001. Retinitis pigmentosa is a group of rare, inherited genetic disorders that lead to progressive peripheral vision loss and night vision difficulties, followed by central vision loss and often blindness. This disorder affects around 100,000 people in the U.S. alone and 14 to 33 per 100,000 people worldwide. RST-001 is a gene therapy application of optogenetics, a therapeutic approach that gives light sensitivity to cells which were not previously or natively light sensitive. RST-001 employs the photosensitivity gene to create new photosensors in retinal ganglion cells in order to potentially restore vision to retinas in which rod and cone photoreceptors have degenerated. In 2014, RST-001 received an Orphan Drug Designation by the U.S. Food and Drug Administration (FDA) for the treatment of retinitis pigmentosa. In August 2015, RetroSense's Investigational New Drug application for RST-001 received clearance from the U.S. FDA. In 2016, RetroSense initiated a clinical trial to evaluate the safety of RST-001 in patients being dosed, and in August, the low dose cohort of patients had been safely dosed, Allergan said.