Last week, pharma giant Schering-Plough (NYSE:SGP) announced that the European Union had approved its blockbuster drug Remicade to treat a new indication. SGP also said that it had begun initial marketing of cholesterol-lowering drug Zetia in Japan.

Johnson & Johnson (NYSE:JNJ) markets Remicade in the U.S., with Schering responsible for most of the international sales of the drug. Last year, Schering's Remicade sales were $1.2 billion; they were up 34% year over year in the first quarter of 2007 as a result of improved labeling for new indications. The EU approval of Remicade now adds yet another new indication for the compound to treat pediatric Crohn's disease.

On Friday, Schering also announced that blockbuster drug Zetia would begin marketing in Japan today. Zetia received the thumbs-up from the Japanese regulatory authorities in April. In conjunction with Remicade, these two compounds will steer the future of Schering's financial performance for the next several years.

Investors often overlook the importance that markets outside the U.S. offer for pharmaceutical products. Japan, for instance, is the second-largest market for pharmaceutical sales in the world when ranked by country.

For Schering-Plough, places like the EU and Japan represent a large chunk of its overall sales, with 60% of its $10.6 billion in sales coming outside the United States. This dependence on foreign markets will only grow with these positive developments for its two top drugs.

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Fool contributor Brian Lawler does not own shares of any company mentioned in this article. Johnson & Johnson is an Income Investor recommendation. The Fool has a disclosure policy.