Astrazeneca was trading lower after the results of a study showed US rival Merck's diabetes drug met heart-safety requirements. The British drug-maker's own treatment for the disease was recently required by US authorities to provide information about the risk of heart failure.Standard Chartered was in the red as it published sinking total revenues, which fell 4% to $4.4bn, a 6% miss against consensus forecasts of $4.7bn "We think that STAN's Q1 2015 IMS offers a preview of the unpalatable impact of planned de-leveraging," Investec said in a note.Centrica surged as its chairman was quoted saying the company has made preparations in the event of a takeover offer.BP was trading higher despite posting an underlying replacement cost profit decline for the three months to end-March. In Tuesday's trading statement, the oil giant said profit for the last quarter came in at $2.6bn compared with $3.2bn for the same period in 2014.Costa Cofee and Premier Inn owner Whitbread made gains as it served up impressive results for the year to 26 February. Revenue rose and underlying profits before tax were both higher, leading to a 19.4% increase in earnings to 213.67p per share, well ahead of the consensus forecast.Wealth management group St James's Place was among the risers as it posted a 22% increase in funds under management to £55.8bn in its latest interim statement.RisersFresnillo (FRES) 739.50p +1.65%Centrica (CNA) 273.00p +1.45%Anglo American (AAL) 1,116.00p +1.13%BHP Billiton (BLT) 1,585.00p +1.02%Marks & Spencer Group (MKS) 552.50p +0.91%Glencore (GLEN) 313.50p +0.42%SSE (SSE) 1,593.00p +0.31%3i Group (III) 512.50p +0.29%BP (BP.) 478.10p +0.25%Old Mutual (OML) 230.70p +0.13%FallersStandard Chartered (STAN) 1,082.00p -3.00%AstraZeneca (AZN) 4,568.00p -2.92%Babcock International Group (BAB) 994.50p -2.88%St James's Place (STJ) 881.50p -2.76%Whitbread (WTB) 5,300.00p -2.57%Aviva (AV.) 522.50p -2.43%Barratt Developments (BDEV) 524.00p -2.42%Carnival (CCL) 3,087.00p -2.25%Imperial Tobacco Group (IMT) 3,252.00p -2.08%Persimmon (PSN) 1,725.00p -1.99%