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It took a few years before Martine Rothblatt got used to describing her daughter’s chronic lung disease as a lucrative market opportunity. “I choked every time I said it - it sounded so immoral,” says Rothblatt, 52. But when she realized that the fastest track to a cure was to launch a biotech firm and then take it public, Rothblatt started United Therapeutics (unither.com).

That was in 1996, and today she is convinced that capitalism is the answer. “I no longer have any doubt about the benefit of using profit motivation to develop cures,” she says. “It’s the language I need to build the company,” she says. “It’s the language that Wall Street understands.”

Rothblatt had no background in biotech: She had started her career as a corporate lawyer and gone on to help launch three successful satellite-communication companies, including Sirius Satellite Radio (Charts). In 1995, Rothblatt sold some of her telecom stock and used the proceeds to fund nonprofit PPH research. But after spending $2 million over two years, she saw little progress and grew discouraged.

She started researching the disease herself and found more than just a potential treatment - she found a business opportunity. The National Institutes of Health estimates that more than 200,000 suffer from PPH worldwide. Each patient pays as much as $150,000 a year for treatment - a $7.5 billion market in the U.S. alone.

After selling her vision of an inhaled PPH therapy to angel investors, Rothblatt tracked down and recruited two scientists who had developed a promising PPH drug at Burroughs Wellcome before it merged with Glaxo in 1995. It took Rothblatt seven months to license the compound, which Glaxo had shelved in favor of Flolan. Rothblatt founded United Therapeutics in 1996 and took the company public three years later.

Reaching her goal of developing an inhaled drug would take years of clinical trials, and Rothblatt had to find a way to keep investors happy in the meantime. “Something I learned from my satellite companies - you have to develop iterations of your products over time, producing real revenues incrementally,” she says.

In 2002 the FDA approved the company’s first version of Remodulin, the compound she licensed from Glaxo. Remodulin, which patients inject under their skin, lasts as long as three hours in a patient’s bloodstream and doesn’t have to be cooled. The drug, say some pulmonologists, is easier and safer to administer than Flolan. Neither a spokesman for Glaxo nor one for the drug’s U.S. distributor would comment on the ease and safety of the use of Flolan.

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