"You can invest for all the right reasons and still get the wrong result," notes long-standing turnaround stock expert George Putnam, referring to the poor performance of the pharmaceutical sector in recent years.

Here, in his industry-leading The Turnaround Letter, he offers a fascinating review of 10 leading drug stocks which he now believes offer a combination of growth potential at "pretty cheap" valuations. Here is his overview.

"In 2000 and 2001, when the Internet boom was becoming a bust, many smart investors turned away from technology stocks and put their money into drug stocks. How could you go wrong with the big pharmaceutical companies?

"Demand for their products was growing as the population aged. These companies had huge research
and development programs that seemed to keep cranking out new blockbuster drugs. And most of them had great balance sheets, with many paying handsome dividends.

"Much of this reasoning has been borne out in the intervening years. Many large drug manufacturers have rung up substantial revenue gains over the last decade. So what's happened to the big drug stocks? With few exceptions they have gone sideways or down – in some cases down a lot.