GlaxoSmithKline says that second-quarter turnover rose 2% to £6.62 billion, while core operating profit fell 2% to £1.94 billion.

Pharmaceutical and vaccines sales inched up 1% to just over £5.30 billion, driven by Advair/Seretide (salmeterol and fluticasone) for asthma and chronic obstructive pulmonary disease. GSK's top-seller rose 5% to £1.36 billion.

The Avodart (dutasteride) franchise, for the treatment of benign prostatic hyperplasia, increased 12% to £221 million, while Lamictal (lamotrigine) for seizures and bipolar disorder, fell 8% to £63 million, due to generic competition. Heart drug Lovaza (omega-3-acid ethyl esters) slipped 2% to £309 million.

However, the results have been overshadowed by a bribery probe into the company's China operations. Chief executive Sir Andrew Witty (pictured) will be speaking later today about the situation but says that "clearly, we are likely to see some impact to our performance in China as a result of the current investigation, but it is too early to quantify the extent of this".

He added that "we are co-operating fully with the Chinese authorities in this matter".

As for other territories, Sir Andrew said GSK's Japan business was down 5%,  while European pharmaceuticals and vaccines sales were flat, due to price cuts and "our strategy to restructure our European operations and re-allocate resources to support identified growth opportunities in the region". He added that "nonetheless, we remain cautious about the outlook in Europe and expect austerity pressures to continue".