Novartis expects sales to grow in the mid-single digits from 2014 once it has absorbed the full impact of competition from cheaper drugs, and said its long-standing chairman and former Chief Executive would step down next month.

The Basel-based group guided investors to expect a mid-single digit decline in its core operating margin on a constant currency basis in 2013, as competition from generic copies knocks $3.5 billion off sales.

The drugmaker is hoping 2013 will be a turning point as it weathers the loss of exclusivity on its top-selling blood pressure drug Diovan in the United States and resolves lingering manufacturing problems at its Consumer Health factory in Lincoln, Nebraska.

Europe's second-largest drugmaker by market value after hometown rival Roche, is relying on sales of its newest products, like multiple sclerosis pill Gilenya and cancer drug Tasigna to help drive future growth.

Novartis said it expected reported sales growth of at least mid-single digits in 2014 and 2015 while core operating income should grow ahead of sales.

Core earnings per share rose to $1.27 in the fourth quarter, compared with the average estimate of $1.31 forecast in a Reuters poll of analysts.

Novartis' figures, which kick off the Big Pharma earnings season in Europe, come a day after U.S. rival Johnson & Johnson posted better-than-expected fourth quarter results, but forecast 2013 earnings below Wall Street forecasts.

Daniel Vasella, who has served as Novartis CEO and Chairman for 17 years, said he would not stand for re-election to the board of directors.

The board has proposed Bayer healthcare head Joerg Reinhardt to replace him. Reinhardt is a former COO of Novartis who had once been tipped as a possible successor to Vasella, but left in 2010 after Joe Jimenez was given the top job.