The strong rate of the pound and the weakness of the dollar have had a major impact on earnings at GlaxoSmithKline in the first quarter but its products are still performing well despite generic competition in the USA.

The UK drugs giant said that its operating profit of £2.17 billion was flat compared to the first quarter last year in sterling terms although that represents an 11% increase at constant exchange rates, while group revenues of £5.59 billion declined 4% when measured in pounds but were up 4% at CER.

Pharmaceutical sales increased 3% to £4.81 billion, with Advair/Seretide (salmeterol and fluticasone) for asthma and chronic obstructive pulmonary disease grew 11% to £835 million, while the type 2 diabetes drug Avandia (rosiglitazone) advanced 19% to £414 million. GSK's vaccine sales rose just 6% to £368 million, though the firm said that was due to a comparision “with an exceptionally high first quarter last year,” but Infanrix/Pediarix combination vaccines for children did manage a 15% rise to £134 million.

Sales of Lamictal (lamotrigine) for epilepsy were up 17% to £250 million, while heart disease drug Coreg (carvedilol) increased 8% to £217 million. Valtrex (valaciclovir) for herpes infections also performed well with a 22% rise in sales to £224 million. On the negative side, however, significant generic competition hit three of GSK’s established products very hard.

The antidepressant Wellbutrin XL, a sustained-release form of bupropion, fell 37% to £109 million, while Zofran (ondansetron), its nausea treatment for patients undergoing chemotherapy for cancer, slumped 60% to £87 million. Revenues of the allergy drug Flonase (fluticasone) fell 49% to £63 million.

Nevertheless, chief executive Jean-Pierre Garnier said that the figures are further evidence that GSK’s broad portfolio, “underpinned with effective cost control,” will continue to deliver strong earnings performance at CER. He added that over 10 products have been filed, approved or launched since the start of 2007 and “these new opportunities, together with those in our very promising late-stage pipeline, will augment and energise further growth.”