Broker tips: GlaxoSmithKline, Serco, Britvic

Jefferies has maintained its 'hold' rating for GlaxoSmithKline (GSK) after Denmark approved the sale of a generic copy of its top-selling inhaled lung drug, Advair."Sandoz/Vectura's EU branded generic of Advair/Seretide was anticipated, though the timing was uncertain. Confirmation of its approval in Denmark underpins our expectation that an increasingly competitive EU respiratory market may see further reference pricing, which could negatively impact Advair, Symbicort [AstraZeneca] and Breo."Panmure Gordon has kept a 'buy' rating for troubled outsourcing outfit Serco despite a disappointing trading update on Thursday, saying consensus estimates for this year are unlikely to change.Panmure Analyst Mike Allen said: "The pre-close statement from Serco shows little change from the profit warning in November. The outturn for 2013E is not expected to materially alter current consensus." He kept his positive stance on the stock, saying that the "current valuation may have captured most of the downside potential for 2014E and beyond".Britvic shares are "up with events" after a strong run, according to Investec which reiterated a 'hold' recommendation on the soft drinks group.After a 65% jump so far this year, Analyst Nicola Mallard said that the "real test of success" is if the company can consistently deliver profitable revenue growth - "something it has yet to prove".BC