Investors hammered Centocor Inc. stock early last week, worried that Merck & Co.'s Aggrastat entry into the GPIIb/IIIa field would cut into sales of CNTO's ReoPro. However, a comparison of data from the two drugs showed they have little to fear, as ReoPro has produced stronger data with a more attractive dosing schedule.

CNTO, which lost $4.875 on the first three trading sessions, rebounded by Friday to close at $33.50, off $0.375 on the week on a total of 14.3 million shares traded.