** Shares of Anatara Lifesciences rise as much as 8.7% to A$0.05, their highest since Aug. 22

** Stock marks biggest intraday pct gain since Sept. 11

** Gastrointestinal health products maker says granted European patent for Gastrointestinal ReProgramming product(GaRP)

** Co says patent is being validated in 19 major European countries and the UK until March 2039

** Stock has more than doubled in value YTD as of 0350 GMT, vs the ASX 200 benchmark , which rose 8.3%

(Reporting by Sneha Kumar in Bengaluru)

((Sneha.Kumar@thomsonreuters.com;))