Replacing injections with pills

At first glance, Irene Pereira de Sousa comes across as modest and respectful. The 29-year-old researcher at ETH’s Institute of Pharmaceutical Sciences speaks calmly and takes care that those around her feel comfortable. “I’m very empathetic; I quite often end up being a mediator,” she says. The daughter of an Italian child psychologist and a Brazilian engineer has already learned plenty from her family about interacting with other people and cultures – skills that now help her to work in multicultural teams in the international world of science.

She always wanted to study

This first impression should not deceive ourselves from her strong will and inner strength. A glance at her CV shows just how purposefully she has pursued her career, step by step – from a student in Padua, Italy, to a postdoc at the Chair of Drug Formulation and Delivery at ETH Zurich.

“I grew up in an academic environment and, as a child, I already knew that I wanted to study later on,” she says. She just needed to find the right subject. While her brother Luis, a year and a half older than her, went into medicine, she chose pharmaceutical chemistry and technology, attracted by the combination of research, chemistry, and helping people by developing pharmaceutical products.

From the town to the world

Beginning her studies was like entering another world. “I grew up in Pordenone, a town in the Friuli-Venezia Giulia region, and I really wanted to make new experiences and become independent.” She first attended the University of Padua, then spent time in Alicante, Spain, as an Erasmus student, before moving to Innsbruck, Austria, for her PhD.

Here, as part of a European project, she researched ways to administer macromolecular substances to patients orally rather than by injection. “This is one of the biggest challenges for scientists in pharmaceutical research,” she explains. For decades, researchers have been looking for a solution that would allow, for example, diabetic patients to take insulin in tablet form rather than by injection – thus far without success. Stomach acids, intestinal enzymes and the protective mucus on the wall of the intestine damage the insulin so much that it loses its efficacy on its way through the digestive tract.

Administering medicines orally rather than by injection

“For my doctoral project, I worked on a nanocarrier that transported drugs safely into the intestine and through the intestinal mucus into the blood, where they could be absorbed and take effect,” explains the young researcher. To do so, she used two strategies.

“One involved penetrating the intestinal mucus by increasing the surface charge density of the nanocarrier.” The other used mucus-degrading enzymes to create a way through. “The important thing was to avoid damaging the mucus too much, as it also has a protective function, for example against bacteria,” says Pereira de Sousa. “If it becomes too permeable, it could harm the patient.” In 2015, Pereira de Sousa received the Principality of Liechtenstein’s prize for outstanding scientific research for her work. She was also selected as an ETH fellow by ETH Zurich and she was awarded a grant for two years in order to continue her research.

Since September 2016, she has been looking for new ways to treat the congenital metabolic disorder phenylketonuria as postdoc in ETH Professor Jean-Christophe Leroux’s research group. Around one in every 10,000 children is born with this incurable disease. Those affected lack a particular enzyme, which means that they cannot break down the amino acid phenylalanine. Instead, it remains in the body and, if the condition goes untreated, leads to severe neurological disorders. “People with this disease have to maintain a strict diet and can only eat fruit, vegetables and special foods without phenylalanine,” explains Pereira de Sousa. “I therefore want to develop microparticles that can carry an alternative enzyme, developed from yeast, to the intestine so that phenylalanine can be broken down at least temporarily.” Her aim is to allow affected individuals to eat normally in the future.

Combining research and family

Although this project is still in its early stages, Pereira de Sousa is already making further plans. She wants to continue her academic career, and a family is also a part of her plan for the future. “Why should I have to choose between career and family?” she asks. “It has to be possible to combine the two.” For the moment, she and her boyfriend, a young Italian doctor currently doing research in Oxford, are focussing fully on their work. It is only in the evenings that Pereira de Sousa takes a few hours off to pursue her passion: dancing. She has been dancing ballet since she was eight, she also does contemporary dance and isn’t shy about showing her skills at performances. “On the stage where I used to dance I have now the honour of presenting my research.”