** Shares of drug developer Eiger BioPharmaceuticals Inc
EIGR.O fall 31% to $5.88 - biggest pct loss in more than 4 yrs
** U.S. FDA says unsure that EIGR's experimental drug,
peginterferon lambda, meets criteria for emergency use
authorization (EUA) in treatment of patients with
mild-to-moderate COVID-19 urn:newsml:reuters.com:*:nPn9p2TmHa
** Drug is in ongoing late-stage trial to treat patients
with severe form of viral hepatitis
** FDA adds it is open to consider any new information that
will support an EUA
** Co says it will provide additional data
** Including session losses, stock up ~13% YTD
(Reporting by Khushi Mandowara)
((Khushi.Mandowara@thomsonreuters.com;))