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.

Shares of Vanda Pharmaceuticals (VNDA -3.54%) jumped up 80% earlier this week on news that the Food and Drug Administration had spoken very positively in a briefing about the company's non-24-hour sleep disorder drug tasimelteon. Investors had until this point largely discounted any chance of the drug being approved, a sentiment that is now reversing course. In this segment from Tuesday's episode, health care analyst David Williamson looks at the drug's chances of FDA approval, discusses his views on Vanda and its prospects, and tells investors whether he still sees the stock as a buy after this pop.

Follow David on Twitter: @MotleyDavid.