As the debate continues over what's causing health-care cost growth to slow -- Obamacare or the poor economy -- we're seeing another catalyst have a big impact: the patent cliff.

Drug spending fell for the first time in 55 years, but not because Americans are living healthier. Simply put, some high-profile drugs just got a lot cheaper.

This video discuses why the patent cliff, while a huge threat to the pharmaceutical industry, is a huge opportunity to decrease costs for one of the largest drivers of the national debt. Our health-care analyst takes a look at why generic-drug makers aren't the obvious home-run investment they would appear, despite strong industry tailwinds.

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

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