Infectious personality.

• Author: Waller, Hailey

With a potential blockbuster drug, Cempra had high hopes. Now, it struggles at the FDA's finish line, minus its lauded founder.

After three decades developing drugs to counteract bacterial infections, Prabhavathi Fernandes appeared on the brink of her biggest hit: a drug to treat pneumonia that she believes could become the best-selling antibiotic ever. Its promise and Fernandes' track record helped attract more than a half billion dollars of financing to Chapel Hill-based Cempra Inc. Investors bid up its stock to more than $2 billion in market value amid optimistic reports from industry analysts. Then, in a few weeks in November and December, the biotech rock star's dreams came to an abrupt halt as federal regulators determined Cempra's drug, Solithera, wasn't ready for prime time.

Fernandes, 68, abruptly left the company she had built over the previous decade. Months later, a slimmed-down Cempra is focused on a rebound, while its former CEO remains shaken. "I don't want to live through another November like that," Fernandes says, fighting back tears.

Her agony isn't over the lost effort or financial setbacks, she says. Rather, she laments one thing: "A lot of people know the facts about our products. Many physicians have wanted to have it available for their patients. They know the data, and the drug wasn't approved. That's the sad part."

While drug companies regularly boom or bust, Fernandes was an unconventional CEO. "I broke the glass ceiling when I became a VP at Bristol-Myers Squibb," she says, "and was liked on Wall Street in spite of being a triple minority in the business world: A woman, an Indian and a scientist."

A native of Bangalore, India, Fernandes earned a master's in microbiology from an Indian medical college. She married a physician, and they moved to Belgium, where her daughter now lives. The couple's next stop was Philadelphia, where Fernandes earned a doctorate, also in microbiology, from Thomas Jefferson University. While teaching at Temple University, she took a research job at the Squibb Institute of Research working for Richard Sykes, who later became chairman of GlaxoSmithKline PLC. That led to an opportunity at Abbott Laboratories, where Fernandes helped develop a set of antibiotics called macrolides that are used to treat bacterial infections. The work spawned Abbott's introduction of Biaxin in 2000; its generic name is clarithromycin. Since then, it has posted revenue of more than $1 billion.

"It's the go-to drug for respiratory-tract infections," the No. 1 reason for doctor visits, Fernandes says.

Fernandes left...