The major side effect observed with Xarelto is bleeding, similar to other anti-clotting drugs.

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There's another major side effect to third-party ownership: Its impact on the new Financial Fair Play regulations that limit the losses clubs wishing to play in lucrative European competition can sustain.

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Merck is working on a drug that counteracts a major side effect of Niacin, an HDL-raiser that is already on the market.

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