** Acer Therapeutics ACER.O shares more than double to
$1.47
** Zevra Therapeutics ZVRA.O says it will acquire ACER
for $15 mln to bulk up its rare disease portfolio
** ACER eligible to receive additional $76 mln upon
achievement of certain milestones for Acer's urea cycle disorder
drug Olpruva and its connective tissue disorder drug Edsivo
** Zevra says it will provide Acer with a short-term loan
for up to $16.5 mln subject to certain conditions
** As of last close, shares down 75.7% YTD
(Reporting by Christy Santhosh)
((Christy.Santhosh@thomsonreuters.com))