** Shares of drug developer Soleno Therapeutics SLNO.O fall ~6% to $54 premarket

** Co says U.S. FDA has extended review of its experimental drug to treat Prader–Willi syndrome, a rare genetic disorder

** The condition causes affected individuals to develop extreme hunger, which leads to chronic overeating, or hyperphagia, and obesity

** FDA determined that co's responses to recent information requests constituted major amendment to marketing application for the drug, diazoxide choline extended-release tablets

** The health regulator will now give its decision by March 27, 2025, compared with its previous action date of Dec. 27 this year

** FDA did not cite any safety, efficacy or manufacturing concerns, SLNO says

** Up to last close, stock up ~42% YTD

(Reporting by Mariam Sunny in Bengaluru)

((Mariam.ESunny@thomsonreuters.com;))