The Dow Jones industrial average briefly turned negative on Wednesday, while the S&P 500 pared gains as shares of major pharmaceutical companies weighed.

The Nasdaq traded near break-even as the semiconductor and drug groups dragged.

The Dow Jones industrial average <.DJI> was up 2.27 points, or 0.02 percent, at 10,408.25. The Standard & Poor's 500 Index <.SPX> was up 1.83 points, or 0.16 percent, at 1,120.14. The Nasdaq Composite Index <.IXIC> was up 2.18 points, or 0.10 percent, at 2,282.97.

Both Pfizer
and Merck traded near their session lows.

(Reporting by Ellis Mnyandu; Editing by Kenneth Barry)