Two big winners in the health-care space today were Emeritus Corp (NYSE:ESC) and Isis Pharmaceuticals (NASDAQ:IONS). In this video from Friday's Market Checkup, Motley Fool health-care analyst David Williamson takes a look at what caused shares to pop.

Seattle-based Emeritus saw shares shoot up more than 35% today on the news that it had agreed to be bought out by Brookdale Senior Living (NYSE:BKD). The combined company will have a presence in 46 states and, with more than1100 facilities, will have a 10% market share. Due to reimbursement cuts from Medicare, scale is vital in this industry, so this could be a very beneficial deal. However, David mentions some caveats that investors will want to keep in mind. He suggests a "wait and see" strategy here, to see if these companies are, in fact, better together than apart.

Also, Isis Pharmaceuticals shot up 15% today after the orphan drugmaker reported positive phase 2 trial results for its drug focused on the rare spinal disorder spinal muscular atrophy. While some analysts have been calling this a potential blockbuster, David tempers enthusiasm, saying it's probably still a bit too early to be making that call. However, he does call attention to the company's partnership strategy and vast number of pipeline assets as indicators that this is definitely more than a one-trick pony, and certainly a company to watch.

David Williamson has no position in any stocks mentioned. The Motley Fool recommends Isis Pharmaceuticals. 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.