Sales of Lipitor rose but Viagra was hit by competition

Pfizer said earnings this year were expected to be in line with market forecasts but performance in 2005 could be affected by stiffer competition.

It reported third quarter profits up 34% at $3.3bn(�1.8bn), as sales of its anti-cholesterol drug Lipitor soared.

However, sales of its best known drug- impotency pill Viagra - fell 15%.

Sales of Viagra were affected by the launch of two competitors.

Strong prospects

Pfizer cautioned that sales in 2005 were likely to be affected by the advent of competitor drugs to four of its most popular medicines.

Patents on anti-fungal drug Diflucan, epilepsy treatment Neurontin, antibiotic Zithromax and hypertension treatment Accupril expire next year.

The four drugs have combined sales of more than $5bn.

Pfizer's long term prospects remain strong Hank McKinnell, Pfizer Check Pfizer's share price

The New York-based company was boosted by a strong third-quarter display.

Sales grew 4% to $12.83bn between July and September.

Lipitor, Pfizer's anti-cholesterol drug, produced a stand-out performance, as sales rose 11% to $2.74bn.

Bextra, an arthritis drug, also performed strongly.

Hank McKinnell, Pfizer's chairman and chief executive, said the firm continued to show strong growth despite increased competition, pressure on prices and a tough regulatory environment.

"While we expect these issues to temper revenue and income growth in 2005, Pfizer's long term prospects remain strong," he said.