From the smallest biotech to the biggest pharmaceutical stock The Motley Fool's Market Check-Up covers the health care sector's biggest headlines, hottest market movers, and Obamacare's ongoing rollout.

In this segment from Friday's episode, health-care analyst David Williamson examines what seems on the surface like a radical shift for Bristol-Myers Squibb (NYSE:BMY). The company has announced that it will discontinue drug discovery in the hepatitis-C, diabetes, and neurological disorder spaces. It will instead focus on a number of treatment areas, singling out immuno-oncology as the most important for the pharma's future.

David takes a close look at this major shift and the reasons behind it, analyzes the space that Bristol-Myers is focusing on going forward, and tells investors whether this move is really as radical as it seems.

David Williamson owns shares of Merck. Follow David on Twitter: @MotleyDavid.

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