** U.S.-listed shares of Calliditas Therapeutics CALT.O
gain 71% at $38.31 in premarket trading after Japan's Asahi
Kasei 3407.T offered to buy co for around $1.1 bln
** Stockholm-listed shares CALTX.ST also up 78.2%
** Asahi's offer of 208 crowns per share for CALT represents
an 83% premium on its closing price of 113.6 crowns on Monday
** With the deal, Asahi gets access to CALT's kidney disease
drug Tarpeyo as well as a mid-stage development candidate which
is being developed for treating a liver disease
** As of last close, U.S.-listed shares are down ~13% YTD
(Reporting by Bhanvi Satija in Bengaluru)
((Bhanvi.Satija@thomsonreuters.com; Outside U.S. +91
9873062788;))