** Shares of Cyclerion Therapeutics CYCN.O fall 8.7% to
$2.27 in afternoon trade
** Drug developer says CEO Peter Hecht will step from his
role after CYCN appoints Regina Graul as president
** Hecht's departure is part of his transition as CEO of a
new company Tisento Therapeutics, which in May bought 2
experimental drugs from CYCN
** CYCN's new president most recently served as vice
president at another drug developer EQRx that was acquired by
Revolution Medicines RVMD.O in early November
** Including session's loss, CYCN's stock down 82.7% YTD
(Reporting by Puyaan Singh)
((Puyaan.Singh@thomsonreuters.com;))