NEW YORK (AFP) - The world's biggest pharmaceutical company, Pfizer, reported on Tuesday a big jump in fourth-quarter earnings, as cost-cutting efforts plus a gain from an asset sale helped offset the loss of exclusivity of a blockbuster cholesterol drug.

Pfizer reported fourth-quarter net income of US$6.3 billion (S$7.8 billion), up from US$1.4 billion in the year-earlier period. The results included a US$4.8 billion gain from the sale of the Nutrition business to Nestle.

However, Pfizer continued to feel the effects of the loss of exclusivity of its popular Lipitor anti-cholesterol drug. Fourth-quarter revenue fell 7 per cent compared with last year's level to US$15.1 billion.

Pfizer's adjusted net income, which excludes one-time items such as the Nestle deal, fell 7 per cent from the year-earlier period to US$3.5 billion.

The pharma giant pointed to a number of promising new drugs that are at various stages of the developmental pipeline. These include the 2013 launches of Xeljanz, which treats rheumatoid arthritis, and Eliquis for the prevention of strokes.

"Overall, I am pleased with our 2012 financial performance, our recent product approvals and our expense reductions," said chief financial officer Frank D'Amelio.

In early 2011, Pfizer undertook a reorganisation of its research activities and eliminated some activities that were seen as ancillary. The company spent less than a year earlier on promotional programs and some corporate functions.

Pfizer also is studying a potential public offering of up to a 19.8 per cent stake in its Zoetis unit, an animal health division.

Pfizer offered 2013 guidance of US$56 billion to US$58.2 billion in revenue, compared with the 2012 level of US$59 billion, and adjusted diluted earnings per share of US$2.20 to US$2.30, compared with US$1.94 last year.

Pfizer shares were up 0.8 per cent in pre-market trading.