US STOCKS-Wall St ekes out gain, helped by materials, consumer stocks
* Allergan, Pfizer drop after biggest-ever healthcare deal
* Alcoa up on report of Elliott stake, boosts materials
* Mallinckrodt up after posting higher sales
* Indexes up: Dow 0.04 pct, S&P 0.09 pct, Nasdaq 0.15 pct (Updates to open)
By Abhiram Nandakumar
Nov 23 (Reuters) - U.S. stocks eked out small gains on Monday morning, helped by gains in materials and consumer stocks, as investors stayed cautious after last week's strong gains and ahead of Thanksgiving.
Five of the 10 major S&P sectors were higher, kept afloat by the 0.53 percent rise in the materials sector, boosted by Alcoa, and a 0.5 percent gain in consumer discretionary stocks.
Pfizer's shares fell 2 percent to $31.54, after the company said it would buy Allergan in a deal valued at about $160 billion, the biggest ever in the healthcare sector. Allergan fell 2 percent to $306.17.
The two stocks were the biggest drags on the S&P 500, while Pfizer was the second-biggest drag on the Dow. But healthcare stocks stayed positive, helped by a gains in insurers. Continuación...