8. Ranexa

Gilead Sign
Evaluate Pharma estimates that worldwide sales of Ranexa (or Latixa) will drop to just about $175 million by 2022.

8. Ranexa/Latixa
Gilead Sciences/Menarini
2016 sales: $748 million

While not quite as big a seller as Gilead Sciences' PAH drug, Letairis, angina treatment Ranexa has been a steady seller, generating nearly $680 million in revenues last year. Gilead collects the U.S. revenue and has a license agreement with Italy’s Menarini for sales outside of the U.S. That part returned about $71 million in sales, according to Evaluate Pharma.

Ranexa has to compete with three other classes of drug that can treat angina, all of which have cheaper generics. Gilead expects generics of Ranexa itself to hit in 2019 when its key patent expires. Evaluate Pharma thinks worldwide sales of the drug will drop dramatically in the coming years, projecting a slide in combined revenues by 2022 to just about $175 million.

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Actually, Gilead doesn’t have a patent to cover ranolazine, the active ingredient of Ranexa. It turns out that only a sustained-release formulation of ranolazine can achieve the therapeutic plasma levels needed to battle angina pain. Gilead has patents on those formulations.

8. Ranexa