US STOCKS-Wall St trims gains, dragged down by biotechs
* Biotechs sell off after Clinton tweet
* Biogen, Gilead biggest drag on the S&P, Nasdaq
* Several Fed officials to speak this week
* Dow up 0.29 pct, S&P up 0.13 pct, Nasdaq down 0.38 pct (Updates to early afternoon)
By Tanya Agrawal
Sept 21 (Reuters) - U.S. stocks lost most of their morning gains on Monday, dragged down by biotechs after U.S. Democratic presidential candidate Hillary Clinton said she would announce a plan to stop "price gouging" for specialty drugs.
The Nasdaq composite and the S&P 500 indexes turned negative as Biogen slipped 4.5 percent and Gilead 1.9 percent.
The S&P healthcare sector fell 1.35 percent, making it the only S&P sector index in the red. The Nasdaq biotech index slumped 4 percent.
The New York Times reported that steep price increases for specialty drugs was partly due to companies buying old, neglected drugs and turning them into "specialty drugs". (nyti.ms/1Yvz0Xl) Continuación...