Drugs giant GlaxoSmithKline's profits have been boosted by strong sales of its new asthma treatment Advair.

The drug helped profits at the world's second-biggest pharmaceutical company rise 17% during the first three months of 2002.

Pre-tax profits climbed to �1.593bn ($2.31 billion) from �1.388bn a year ago.

Advair, also sold as Seretide, made �699m worldwide over the three month period, lifting total asthma drug sales to �967m.

Patent concerns

But the company, which was created by the merger of Glaxo Wellcome and SmithKline Beecham in December 2000, still faces investor concern over its long term prospects.

Worries over the strength of patents on antibiotic Augmentin and antidepressant Paxil have seen its share price underperform this year.

Glaxo faces legal challenges to its patents on both products, which are unlikely to be resolved until 2003 or 2004.

The pharmaceutical industry worldwide has been struggling with patent challenges and competition from generic medicines in the last year, with a spate of profit warnings.

However, Glaxo chief Executive Jean-Pierre Garnier said he predicted "mid-teens" earnings growth for the full year and "low-teens or better" in 2003.

There has been speculation that Glaxo may consider another strategic acquisition to avoid a slowdown in growth after 2003, with US group Bristol-Myers Squibb one target identified.