U.S. Stocks End Week With a Whimper, Book Weekly Loss

U.S. stocks ended the week with a whimper, turning big opening gains into losses by the end of the session Friday. A sharp selloff in biotech and health-care stocks spread to broader markets. The S&P 500 closed less than a point lower at 1,931.34 and booked a 1.4% weekly loss. The Dow Jones Industrial Average was able to hold on to a daily gain, buoyed by a 9% jump in Nike Inc. . The blue-chip index closed 113.35 points, or 0.7%, higher at 16,314.67 and declined 0.4% over the week. The Nasdaq Composite ended the day down 47.98 points, or 1%, at 4,686.50 and posted a 2.9% weekly loss.