Novo Nordisk
Projected 2018 sales:
$1.499 billion
2012 sales: $1.543 billion

Novo Nordisk's ($NVO) NovoSeven is getting old. The hemophilia drug has been on the market for years, and sales are losing steam. Its aging has prompted the Danish company to expand its presence in the hemophilia market, but those efforts have not quite gone according to plan.

Last September, Novo was forced to end development of vatreptacog, a drug it hoped could help replace lagging sales of NovoSeven, because of antidrug antibodies discovered in some patients. And the timing was less than ideal: Competition in the hemophilia market is mounting, with biotech giant Biogen Idec ($BIIB) making progress toward getting there with its long-acting clotting factor for hemophilia B patients.

In the past, NovoSeven, approved for patients who lack a particular clotting gene or those who can't tolerate alternative hemophilia drugs, has been used heavily off-label to treat hemorrhagic strokes and prevent bleeding during heart surgery. But a couple of years back, those uses were proven to introduce additional risks, like blood clots in the heart or brain.

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