** Shares of Sihuan Pharmaceutical Holdings Group 0460.HK jump 9.3% to HK$1.64, their highest level since February 2022

** Stock marks its biggest intraday pct rise since July 14, and is second-biggest pct gainer in the healthcare index .HSCIH, which rises 1.6%

** Company said it had on September 2 repurchased 13.1 million shares in the open market at an average price of HK$1.4945 apiece for HK$19.6 million ($2.51 million)

** Sihuan says it has made positive progresses in new businesses of medical aesthetics and innovative pharmaceuticals and it expects launch of a large number of flagship new products to bring strong momentum to future revenue and profit growth

** Hang Seng Biotech Index .HSHKBIO rises 1.7%, benchmark Hang Seng Index .HSI adds 0.03%

** YTD, Sihuan stock up 143.9%, Hang Seng Index up 27.2%

($1 = 7.8113 Hong Kong dollars)

(Reporting by Donny Kwok)

((donny.kwok@thomsonreuters.com))