During the State of the Union address tonight, President Trump is expected to call for an end to the spread of HIV in the U.S. by 2030. There’s a drug already on the market that could help make that a reality. It’s called Truvada — otherwise known as PrEP (for Pre-Exposure Prophylaxis) — and when taken as a preventive, it can drastically reduces transmission of HIV. New York City health officials already credit it with playing a major role in cutting the rate of new HIV infections in the five boroughs by 18 percent. The downside? It can cost upward of $1,600 a month.

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