Updates
** Applied Therapeutics' APLT.O shares fall 72.1% to $2.39, set for a record single-day drop
** The U.S. FDA on Wednesday declined to approve APLT's drug to treat galactosemia, a rare genetic metabolic disease
** The FDA's letter cited "deficiencies in the clinical application" for the drug, called govorestat, APLT says
** Brokerage William Blair says the letter was "unexpected and disappointing" but believes it does not increase the regulatory risk for govorestat's approval for SORD deficiency, another rare genetic metabolic condition
** Including session's losses, stock down 28.4% YTD
(Reporting by Kamal Choudhury)
((Kamal.Choudhury@thomsonreuters.com;))