GlaxoSmithKline, Europe's biggest drug maker, booked a 14.9-percent increase in net profits for 2006, buoyed by soaring sales in the United States and despite a poor performance in Europe.

The British pharmaceutical group also issued better-than-expected earnings guidance for the current financial year.

Net profits surged to 5.4 billion pounds (8.2 billion euros, 10.6 billion dollars) in 2006 compared with the previous year, GSK said in a results statement.

Revenue increased by 7.2 percent to 23.2 billion pounds, while pre-tax profits climbed 19 percent to 7.8 billion pounds.

Sales in the United States surged by 16 percent to 10.4 billion pounds, while European sales edged up 1.0 percent to 5.5 billion pounds.

But Seretide/Advair and the Avandia diabetes treatment experienced slowing sales last year, generating revenues of 3.3 billion and 1.6 billion pounds respectively.

Demand for the two blockbuster drugs -- which comprise one fifth of group revenues -- has waned recently and both face competition from new market entrants, analysts said.

Meanwhile, investors welcomed news that the group expects 2007 earnings-per-share growth of between 8-10 percent. Most analysts had expected growth of about 5.0 percent.

As a result, GSK saw its shares soar in mid-afternoon trading, jumping 1.64 percent to 1,423 pence, giving the group a stock market capitalisation of some 81.8 billion pounds. London's FTSE 100 shares index, on which the group trades, slid 0.39 percent to 6,344.60 points.

"Sales growth is coming from an ever widening portfolio of fast-growing products, and sustained improvements in margin have enabled us to deliver a strong financial performance," said GSK chief executive Jean-Pierre Garnier in the results statement.

"We also have very healthy momentum in our pipeline, with 10 new products added to our late-stage development efforts in the last 12 months."

Pharmaceutical companies refer to their portfolio of drugs that are under development as their "pipeline." Drugs in the late stages must complete final rounds of clinical trials and gain regulatory approval before entering the market.

Garnier added: "We now have over 30 significant product opportunities in phase III development or registration, including five major new products planned for launch this year.

"For all these reasons, we look to the future with confidence."

GSK has five major new drug launches on the cards this year, including Tykerb for breast cancer and cervical cancer vaccine Cervarix.