These miniature intestines are the size of a Nerd candy, but could have a big impact on drug testing

Imagine this: There’s a new drug being floated for its potential to help ease cancer symptoms or even prolong life for certain patients. It’s a long way off from being tested in a clinical trial. And adverse side effects in humans remain a mystery because it’s only been tested in mice. According to biopharmaceutical industry groups, it takes 10 to 15 years on average for one new drug to make it to market. Madeline Eiken ’19 has helped create a middleman of sorts that could transform how drugs are tested for safety and get them developed more quickly.

Eiken cofounded Intero Biosystems, which develops miniature human organs for preclinical drug testing. Currently pursuing her Ph.D. in biomedical engineering at the University of Michigan, Eiken is studying how to scale up models similar to Intero Biosystems’ flagship product, GastroScreen. Derived from adult human stem cells, GastroScreen is an intestinal organoid containing functioning blood vessels, muscle, neurons, and intestinal lining. But whereas a human’s intestines are a six-foot tube, this organoid is “the size of one Nerds candy,” Eiken explains.

The tiny glob may not look like much to the naked eye, but put the it under a microscope and you’ll see, “it’s really, really complex. It captures all the cell types of the intestine while also being small, so you can screen many drugs at once,” Eiken says. “And we can make thousands at a time.”

Why the intestines? Because so many drug side effects affect the gut. Think about the list of potential side effects on almost every over-the-counter or prescription drug: upset stomach, nausea, constipation, diarrhea. “We hope to one day be a source of lots of different types of organoids but what we’re really good at right now is intestines,” Eiken says.

There are many different ways to test drugs on the organoid. For example, Eiken says, they can induce intestinal fibrosis, or excessive scar tissue on the intestinal wall, commonly caused by diseases such as Crohn’s or irritable bowel syndrome. Then a drug is introduced and the organoid is monitored to see if any observable characteristics of the disease have been resolved. “Similarly, we can drop chemotherapies and see cell death or changes in the types of proteins present,” she says, “and we’ll probe what the side effects are.”

Intero Biosystems launched in 2024 and Eiken says the plan was to go slow, apply for grants, scale up modestly. But things have been moving fast. Most recently, Eiken’s team won first place at the Rice Business Plan Competition at Rice University, the world’s largest student start-up pitch competition, netting $900,000 in investment prizes.

Before that, Eiken returned to her alma mater to go through the Bronco Ventures Accelerator, an intensive training for entrepreneurs to grow their businesses offered through the Ciocca Center for Innovation and Entrepreneurship. “I got a lot of basics on how to run a company and learn how to tell our story in a compelling way,” Eiken says. “It was a great experience. And of course I enjoy any excuse to come back to Santa Clara.”

Eiken attributes a lot of where her career path has taken her to SCU, where she majored in biomedical engineering. “While I was there, doing research in the chemistry department, I loved the process of research, the process of thinking about the big questions of the world, and finding ways to answer them with science,” she says.

During her senior year, Eiken’s father was diagnosed with brain cancer and she witnessed his eager search for clinical trials and experimental treatments. Ironically, she was doing research on the ethics of clinical trials as a Hackworth Fellow for the Markkula Center of Applied Ethics. “A lot of people see them as a way to cure their disease and access the best medicine, but in reality, the vast majority will fail due to efficacy issues or toxicity,” says Eiken, whose father is still alive. “That’s why I think it’s important to identify these things in preclinical testing, so we can actually get the outcomes we all want.”