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The Bezos family just donated $100 million to help achieve one of Mayor Zohran Mamdani’s top campaign promises

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Meet Amanda Calabrese, whose Sequel aims to take tampons to the next level

By
Polina Pompliano
Polina Pompliano
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By
Polina Pompliano
Polina Pompliano
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August 10, 2023, 6:00 AM ET
Amanda Calabrese
Courtesy of Sequel

In 2018, Sequel cofounder Amanda Calabrese was an undergrad at Stanford when she was given the following assignment: Come up with a startup business plan in 10 weeks and present it to the class.

Calabrese teamed up with Greta Meyer, and they identified a problem specific to their shared experience as female athletes.

For 10 years, Calabrese had competed for the United States in the sport of lifesaving, often wearing a blue bathing suit, while Meyer played lacrosse at Stanford in a white uniform. “We landed on menstrual products because it was something that was really top of mind for both of us,” Calabrese says. 

They decided to pair their love of design with their studies in mechanical engineering to build a tampon designed to be more fluid-mechanically efficient to help prevent leaks.

When they presented to the class, Calabrese and Meyer met a guest judge, who became their first angel investor. The two founders ultimately turned their class project into Sequel.

What was your “aha moment” for founding Sequel? 

In our consumer research, we kept hearing about this phenomenon we like to call “the red line effect.” People were telling us that they would take out the tampon and notice a red line down the side where it was leaking, yet a whole part of the tampon was bare—it wasn’t even reaching the core. When we heard, “It’s not even reaching the core,” that was a fluid-mechanics moment for us.

If we could design and build a more fluid-mechanically efficient tampon, to actually use tampons until they’re full, we can have a tampon that is designed to absorb more evenly. 

So we’re sitting in a dorm room talking about these linear channels that were causing “the red line effect”—and that’s where the engineering came in. It was like, “Oh, my God, a spiral or a helical shape would create a longer flow path than a vertical channel.”

What is your biggest challenge?

There are three big challenges.

Tampons are regulated by the FDA. They’re a Class 2 medical device. We actually need to get regulatory approval before we are able to go to market because we have owned the innovation of the device.

The second is the manufacturing hurdle. You have to find a manufacturer you like, and you stay with them for the long haul.

The third is entering a really crowded space, where Procter & Gamble has a massive chunk of the market share. And they are the ones who have driven a lot of the innovation in the space—the LeakGuard protection, the braid string, and the anti-slip grip applicator. So coming in as a little fish, we need to really effectively tell our story to our customers, because they’re not expecting innovation from anybody but the big companies.

What is one fun fact about you that people may not know? 

I competed for 10 years on the U.S. national team in the sport of lifesaving. I’m a six-time national champion in the event of “beach flags.”

The Fortune Founders Forum is a community of entrepreneurs chosen by Fortune’s editorial team to participate at the annual Brainstorm Tech conference, which took place in Deer Valley, Utah, in July. Our inaugural cohort was selected based on a variety of factors, including the potential impact of their companies, and reflected a diversity of geographies, sectors, and demographics.

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By Polina Pompliano
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