** Shares of drug developer GRI Bio GRI.O rise 18% to $1.43 in after-hours trading

** Co says its experimental drug, GRI-0621, showed promising results in a mid-stage clinical trial for idiopathic pulmonary fibrosis

** IPF is a chronic lung disease with limited treatment options, co says

** Nearly 40% of treated patients saw better lung capacity vs 80% decline on placebo — GRI

** Trial enrolled 35 patients, most on existing IPF drugs; blood tests suggest reduced lung scarring — GRI

** Including session's move, stock down ~91% YTD

(Reporting by Sahil Pandey in Bengaluru)

((Sahil.Pandey@thomsonreuters.com))