** Shares of Hansoh Pharmaceutical Group 3692.HK fall 8.7% to HK$35.46, on course for the biggest one-day drop since April 7

** Stock hit the lowest level since August 12; third biggest pct loser on healthcare index .HSCIH, which slips 0.6%

** Hansoh plans sales of 108 mln new shares to third party investors in share placement, raising HK$3.92 bln ($502.31 mln)for R&D of new drugs in oncology and autoimmune, among others, and to expand and upgrade laboratories and production facilities

** Says the new shares will be issued at HK$36.30 apiece, representing a 6.5% discount to Tuesday's close of HK$38.82

each

** Hang Seng Biotech Index .HSHKBIO and the benchmark Hang Seng Index .HSI both slip 0.4%

** YTD, stock up 109%

($1 = 7.8039 Hong Kong dollars)

(Reporting by Donny Kwok)

((donny.kwok@thomsonreuters.com))