In this video, health-care analyst David Williamson discusses the FDA's shocking rejection of two drugs they already approved. Gilead Sciences received a complete response letter for HIV drugs elvitegravir and cobicistat, both of which are currently components of the big biotech's quad pill Stribild.

Watch and find out why the FDA came to this conclusion, and what it means for Gilead and investors.

David Williamson has no position in any stocks mentioned. Follow David on Twitter: @MotleyDavid. 

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