**Shares of clinical-stage immune-oncology co Imugene

rise as much as 14.6% to A$0.055; biggest intraday pct gain since Sept. 2

** U.S. FDA gives orphan drug status to co's VAXINA treatment, aimed at treating cholangiocarcinoma, a form of bile tract cancer

** FDA grants orphan drug status to promote drug development for rare diseases affecting fewer than 200,000 people in the U.S.

** Co says orphan status gives it range of incentives including tax credits, potential grant funding and 7-year market exclusivity

** About 56.7 mln shares change hands vs 30-day avg volume of about 23.7 mln shares

**Stock down 54.5% YTD

(Reporting by Nikita Jino in Bengaluru)

((Nikita.Jino@thomsonreuters.com;))