Wall St. drops after news of drug takeover
* Large mergers and acquisitions are generally viewed as a show of support for equity valuations, but analysts said with major indexes trading around 12-year lows, evidence of thawing credit markets and economic recovery is needed to bring investors back into the market.
* The Dow Jones industrial average fell 79.89 points, or 1.21 percent, to end unofficially at 6,547.05. The Standard & Poor's 500 Index lost 6.85 points, or 1.00 percent, to 676.53. The Nasdaq Composite Index shed 25.21 points, or 1.95 percent, to 1,268.64.
(Reporting by Leah Schnurr; Editing by Jan Paschal)