Pfizer (NYSE: PFE) and Bristol-Myers Squibb (NYSE: BMY) are celebrating approval of their blood-thinning drug Eliquis in Europe for atrial fibrillation. In this video, Motley Fool health care analyst David Williamson talks about why the approval was largely expected and therefore didn't drive share prices much, why the drug's U.S. rejection back in June was more of a minor setback than a major blow, and just how big of a drug this is going to be for both companies.

Brenton Flynn has no positions in the stocks mentioned above. David Williamson owns shares of Johnson & Johnson and Pfizer. The Motley Fool owns shares of Johnson & Johnson. Motley Fool newsletter services recommend Johnson & Johnson. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.