** Shares of YiChang HEC ChangJiang Pharmaceutical Co Ltd rise as much as 10.9% to HK$7.94, the biggest intraday percentage gain since March 22
** Stock hits its highest since April 30; among the 30 biggest percentage gainers on the Hong Kong bourse
** Company based in central province of Hubei says its newly acquired aripiprazole and rivaroxaban tablets won bid for centralised procurement, and sales volumes are set to increase significantly
** Says improved income structure will have a positive impact on future operating performance
** The Hong Kong Hang Seng Commerce & Industry Index rises 1.5%
** The Hang Seng China Enterprises Index climbs 1.4% and the benchmark index gains 1.1%
** By last close, the stock had fallen 18.9% this year