LONDON (AP) _ Strong sales for its respiratory, antiviral and central-nervous-system drugs helped boost GlaxoSmithKline PLC profits by 13 percent last year, the company announced Wednesday.

Pretax profit for the year ending Dec. 31 was 5.33 billion pounds ($7.73 billion), or 61 pence per share (88 cents), up from 4.71 billion pounds, or 52.7 pence per share, in 1999.

The year-end results are pro forma, reflecting the combined results of Glaxo Wellcome PLC and SmithKline Beecham PLC, whose long-delayed merger was completed Dec. 27.

The results ``demonstrate that in the new company, we have underlying strength which wasn't slowed by the long pregnancy pause of the merger,'' said CEO Jean-Pierre Garnier.

Total sales for the year rose 12 percent to 18.08 billion pounds ($26.22 billion), with drug sales _ which account for 85 percent of Glaxo SmithKline's sales _ rising 10 percent.

The consumer health care division, however _ which markets over-the-counter products such as toothpaste and sports drinks _ posted only a 3 percent rise in sales, and consumer health care sales fell by 3 percent in the U.S. market.

Overall, though, the company reported strong growth in the U.S. market, where Glaxo does half its pharmaceutical business. U.S. drug sales rose 15 percent.

In Europe, which accounts for nearly a third of pharmaceutical sales, sales rose 6 percent. But sales fell by 2 percent in Britain.

Sales of new drugs accounted for 17 percent of the 15.43 billion pounds ($22.33 billion) the firm reaped in drug sales.

The asthma drug Seretide _ due to be launched in the United States in April under the name Adavir _ posted sales of 208 million pounds ($302 million). Avandia, a diabetes drug launched in the U.S. last year, posted sales of 462 million pounds ($670 million).

Sales of respiratory drugs rose 15 percent at constant exchange rates, while sales of central nervous system drugs, led by the antidepressant Seroxat/Paxil, were up 16 percent. Antivirals _ including the company's HIV treatments _ rose 15 percent. Sales of the firm's HIV drugs grew 14 percent.

The company said it retained its leadership in anti-viral drugs with the launch of Trizivir, the first triple-combination treatment for HIV.

GlaxoSmithKline shares were up 3 percent Wednesday to 1,900 pence ($27.42).