* Futures down: Dow 19 pts, S&P 1.75 pts, Nasdaq 5 pts
By Abhiram Nandakumar
Oct 27 (Reuters) - U.S. stock index futures were slightly lower ahead of the start of a Federal Reserve policy meeting and as investors digested a barrage of earnings reports.
* Global markets fell as a four-week rally in China lost steam and weak results from major companies sent European stocks sliding.
* All eyes are on Apple, which reports fourth-quarter results after the close, as investors await commentary on the iPhone maker's business in China and its forecast for the crucial holiday quarter.
* Alibaba shares rose nearly 10 percent to $83.50 in premarket trading after the e-commerce giant reported better-than-expected revenue.
* Pharmaceutical majors Pfizer and Merck were little changed after they reported results.
* Ford fell 1.5 percent, while Comcast was down 2 percent after results.
* Twitter will post results after the close.
* Strong results from tech majors and blue chips have helped improve analyst sentiment on quarterly earnings.
* S&P 500 earnings are now expected to have declined 2.8 percent in the quarter, based on actual results from about 35 percent of companies and estimates for the rest, compared with a 4.2 percent decline forecast at the start of the month, according to Thomson Reuters data.
* The Fed begins its two-day policy meeting on Tuesday. Expectations of a rate increase this week are low, but investors will focus on the central bank's interpretation of economic data and global financial events.
* Data scheduled for release on Tuesday includes orders for U.S. durable goods for September, which is expected to have declined for the second straight month. The data is due at 8:30 a.m. ET (1230 GMT).
* The index of consumer attitudes is forecast to remain steady in October from the previous month when it rose to 103.0, the highest since January. The Conference Board report is due at 10:00 a.m.
* Dupont fell 2.3 percent to $59.00 after it reported that its quarterly profit halved.
* Novartis' U.S.-listed shares fell 2.3 percent to $90.17 after the Swiss company said a $390 million settlement for a U.S. kickbacks case hurt profit.
* T-Mobile, which began trading on Nasdaq on Monday, rose 2.8 percent ahead of its results before the bell.
Futures snapshot at 6:45 a.m. ET:
* S&P 500 e-minis were down 1.75 points, or 0.08 percent, with 76,490 contracts traded.
* Nasdaq 100 e-minis were down 5 points, or 0.11 percent, on volume of 13,809 contracts.
* Dow e-minis were down 19 points, or 0.11 percent, with 10,521 contracts changing hands. (Reporting by Abhiram Nandakumar in Bengaluru)