Drug Drop Slams Pfizer

Updated from 12:12 p.m. EST

Pfizer's(PFE Quote) shares plunged Monday as investors reacted with fury to the company's decision to stop working on a cholesterol drug that had been viewed as the foundation for the years ahead.

In a staggering setback for its research efforts and an ominous warning about future sales and earnings growth, Pfizer said Saturday night that it would halt development on torcetrapib because more deaths than expected occurred in a big clinical trial.

Shares of Pfizer dropped $2.96, or 10.6%, to $24.90 in extremely heavy trading. The stock sank as low as $23.50. Nearly 290 million shares changed hands, roughly nine times the average volume. ...