This article has been adapted from our sister site across the pond, Fool U.K.

If things are going generally badly for a company, but that company simultaneously tells you it is raising its earnings forecasts and promises more cash back, it has to be taken seriously.

Add to that the fact that the company, AstraZeneca (NYSE: AZN), is the only company in the FTSE 100's top 20 that can also boast a net cash position, and you can see the case for its being the best share in the top UK index.

To go further still, in my own recent simplistic trawl of FTSE 100 companies' price-to-earnings prospects, AstraZeneca came home in seventh place, and it's just one place further down the list on yield.

So what's the problem?
A real stalwart, then -- so what's the problem with the UK's second biggest drugmaker?

Well maybe, just maybe, there isn't one. The well-documented "patent cliff" will undoubtedly see the company face increased competition following the expiry of exclusive rights to its treatments around the world, but this is known and in the price.    

But then there are many products in its development pipeline, while sales of existing drugs such as cholesterol product Crestor and asthma medicine Symbicort are holding up well.

The impending loss of sales of heartburn aid Nexium and schizophrenia medicine Seroquel may be offset by recent U.S. Food and Drug Administration approval of new heart-treatment drug Brilinta, which had already been approved in 41 other countries.

Looking up
Meanwhile, Thursday's half-year results saw the company raise its full-year guidance to earnings of $7.05 to $7.35 despite an ordinary second quarter. This places the shares on a P/E of less than 7. A fair old chunk of fear is therefore factored in, though brokers see earnings falling in 2012.

AstraZeneca also says it will buy back more of its own shares, thus magnifying EPS somewhat, following the sale of its dental business Astra Tech. The company estimates that net share repurchases could increase to $5 billion in 2011.

I'd rather receive some cash by way of a special dividend, but either way, it's good news -- and I continue to view AstraZeneca as a high-yielding bargain for a long-term investment. 

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This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.