Maky Zanganeh was born in Tehran in 1970, nine years before the Islamic Revolution convulsed Iran. She remembers one night in particular, when the military police tear-gassed a house at the end of the cul-de-sac next to where her family lived and sprayed it with machine gun fire. She and her two older sisters were home alone. “In the morning, we woke up at 7 o’clock and had to go to school as if nothing happened,” she says matter-of-factly. “That was my life when I was in Iran.”

Mauricio Candela for Forbes

That preternatural composure and no-nonsense attitude has helped Zanganeh navigate a life filled with more twists and turns than a Persian bazaar. A couple years after that horrific night in Tehran, Zanganeh’s parents, both architects, fled Iran for Germany. She got a degree in dentistry, then an MBA, but ended up working for an American medical robotics outfit, where she met Bob Duggan, a prominent Scientologist, serial entrepreneur and eventual billionaire with whom she would have a son and later marry. She earned hundreds of millions as an investor and executive, speaks four langua­ges (Farsi, German, English, French), survived breast cancer and runs, as co-CEO with Duggan, Miami-based Summit Therapeutics, a Nasdaq-listed biotech that has minted her a $1.5 billion fortune of her own. That wealth has landed Zanganeh, now 54, on Forbes’ list of America’s Richest Self-Made Women (at No. 23) for the first time. She is one of 38 self-made female U.S. billionaires on the list, and one of just five to have made a billion-dollar-plus fortune in health care.

When she and Duggan took over Summit in 2020, the company had less than $1 million in revenue, tens of millions in losses and just one promising drug in its pipeline, an antibiotic that was shelved in 2022. In less than five years, Zanganeh and Duggan—who married in December—have become biotech stars. Key to their success: licensing an overlooked cancer drug candidate from a company in China. That drug, ivonescimab, now seems likely to be a blockbuster. In a clinical trial last year, it outperformed Keytruda, the world’s best-selling drug, which generated nearly $30 billion in 2024 sales for Merck. Investors have driven up Summit shares 575% over the past 12 months, giving it a recent market capitalization of nearly $21 billion, despite having no revenue.

“I think of her as probably the most underrated executive in all of biotech,” says Ken Clark, a partner at law firm Wilson Sonsini Goodrich & Rosati, who for more than three decades has worked with hundreds of biotech companies and served on multiple boards—including that of Summit Therapeutics. According to Clark, Zanganeh stands out because of how she and Duggan, neither of whom comes from a traditional biotech background, work together to question established wisdom and get things done quickly in unconventional ways.

Ivonescimab is now in multiple Phase III trials for different forms of lung cancer, and Summit........

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