10. Orkambi

Vertex Pharmaceuticals
Cystic fibrosis
2015 sales: $351 million
2020 projection: $5.45 billion

When Orkambi, a combination med containing Vertex' ($VRTX) Kalydeco, won FDA approval earlier this year, the company believed it could eventually expand its treatable population by tenfold. Unlike Kalydeco--initially approved only for cystic fibrosis patients with a mutation affecting only 4% of CF patients worldwide--Orkambi has the potential to benefit 8,500 patients age 12 and older in the U.S. alone. That's more than four times the number currently eligible for Kalydeco.

A larger group of patients on the drug won't be the only thing that helps it rake in serious sales. Orkambi, with a sticker of $259,000, also bears an orphan drug price, despite its larger patient pool--a fact that has pricing critics up in arms.

Vertex has a four-point justification for the high cost, as chief commercial officer Stuart Arbuckle laid out on a conference call following Orkambi's approval. There's the size of its patient population, still relatively small when compared with other meds; the clinical benefit of a therapy that treats the underlying cause of CF; the time and cost Vertex plowed into bringing the med to market; and the need to invest in further R&D to aid thousands of other patients with different forms of the disease down the line, he said.

Payers, though, have been laying the groundwork for their discount arguments since before the FDA gave Orkambi a nod. In May, Prime Therapeutics forecast that if priced on par with solo Kalydeco, the new tandem could run the pharmacy benefits manager $367,000 per patient per year, with medical and pharmacy costs included. Lifetime treatment cost for a patient beginning therapy at age 12: $10.3 million, the PBM figured.

Meanwhile, there could be some competition down the road. Recently, Concert Pharmaceuticals said it was able to show that by replacing a single hydrogen atom in Kalydeco with deuterium, it achieved better results in a small, early-stage clinical trial. -- Carly Helfand (email | Twitter)

For more:
Vertex's 2016 outlook falls short amid mixed results from high-profile CF meds
CF specialists up in arms about $259K price for new Vertex med Orkambi
Look out, payers. Vertex's new CF med Orkambi is one step closer to market

10. Orkambi