Witness hypertension drug Vasotec, which lost its protection last year and saw sales plunge.

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The loss of drugs like Vasotec and Prilosec will cost Merck billions, Ricardo says.

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Not that Merck didn't have the goods: Vasotec, Mevacor and now Fosamax are great successes.

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By June, it will lose patent protection on four drugs--Vasotec and Prinivil for hypertension, Mevacor for high cholesterol and Prilosec, which it shares with AstraZeneca (nyse: AZN - news - people), for ulcers.

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