** Shares of gene therapy developer Regenxbio RGNX.O rise 23.6% to $8.59 premarket
** RGNX says it has partnered with Japan's Nippon Shinyaku Co 4516.T to develop and commercialize two gene therapies, RGX-121 and RGX-111, to treat Mucopolysaccharidoses (MPS) Diseases
** MPS is a group of inherited metabolic diseases where the body lacks specific enzymes needed to break down complex sugars
** RGNX will receive $110 mln as upfront payment and up to $700 mln as milestone payments from Nippon Shinyaku
** Deal expected to close by the end of Q1 2025
** All 11 brokerages rate the stock "buy" or higher; their median PT is $38 - LSEG
** RGNX fell ~60 in 2024
(Reporting by Kamal Choudhury in Bengaluru)
((Kamal.Choudhury@thomsonreuters.com;))