** Shares of Island Pharmaceuticals ILA.AX rise as much as 13.3% to A$0.170, their biggest intraday pct gain since Nov 27

** The drug company says the United States Patent and Trademark Office has granted a key patent for its drug ISLA-101

** Patent covers a method of reducing severity of one or more symptoms of dengue virus by administering ISLA-101 - co

** ILA stock up 89.5% YTD, as of 1204 GMT

(Reporting by Adwitiya Srivastava in Bengaluru)

((Adwitiya.Srivastava@thomsonreuters.com;))