PHARMACEUTICALS group GlaxoSmithKline (GSK) posted a 17 per cent fall in second quarter profits as it continued to suffer from the impact of generic competition.

The blue chip group, which said copycat versions of anti-depressant drugs Paxil and Wellbutrin had eroded sales, saw pre-tax profits fall to £1.63bn in the second quarter of the year.

But outstanding growth by newer products was helping it overcome competition elsewhere and meant turnover on a constant currency basis was up two per cent, at £5.06bn.

GSK said asthma drug Advair and diabetes treatment Avandia performed particularly well, with sales up 22 per cent and 59 per cent respectively during the three months to June 30.

The weak US dollar affected the results, and meant that operating profits fell by nine per cent to £1.71bn, a fall of one per cent when measured on last year's exchange rates.

Although the third quarter would be challenging, GSK said it expected a return to earnings growth in the fourth quarter.

Sales of consumer healthcare products rose by four per cent to £798m and were boosted by products including Aquafresh, sales of which were up eight per cent in Europe. Pain reliever Panadol saw a 17 per cent increase in revenues, helping lift over-the-counter medicine sales by two per cent to £357m.

GSK also said excellent growth by energy drink Lucozade, with sales up 16 per cent, contributed to a ten per cent increase in sales of nutritional products.

Jean-Pierre Garnier, chief executive, said he was pleased with the progress of its research and development pipeline, which would fuel growth in the long term.

Products being developed include Boniva, a treatment for osteoporosis, and Entereg, a drug to treat the gastrointestinal side-effects of surgery.

Drugs due to be launched in the next six months include HIV treatment Epivir/Ziagen, a single tablet that eliminates the need for so-called cocktail treatments.

Others are Avandaryl for diabetes, Rotarix for treating rotavirus gastroenteritis in children and Vesicare for people with overactive bladders.

Glaxo said sales of Coreg - a treatment for heart failure - grew by 50 per cent to £113m as is continued to benefit from data showing the drug could significantly reduce the risk of death from a heart attack or stroke.

Lamictal, which is used to treat bi polar depression, increased its sales to £171m. Sales of genital herpes treatment Valtrex rose to £145m.