A Study To Compare The Putative Anxiolytic Effect Of 2 New Drugs In Subjects With Social Anxiety Disorder

GSK561679 tablets are white film-coated tablets, containing 200 (milligrams) mg of the free base, GSK561679A.

GW876008 tablets are white to off-white round film-coated tablets, containing 100 mg of GW876008X (free base).

Alprazolam capsules 0.25 mg are hard gelatine capsules containing 1 tablet of commercial alprazolam (Xanax 0.25).

GW876008 placebo tablets will visually match the active GW876008 tablets. GSK561679 placebo tablets will visually match the active GSK561679 tablets. Placebo to match Alprazolam is a hard gelatine capsule that will visually match the active but containing only a filler.