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  • Katherine Connor

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  • Katherine Connor

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Bioengineering Alumnus on COVID-19 Antiviral Pill Development Team

Britton Boras

Jacobs School of Engineering alumnus Britton Boras earned a Ph.D. in bioengineering in 2015, conducting research with Professor Andrew McCulloch on multi-scale modeling of biological systems. Now a Senior Principal Scientist at Pfizer, Boras uses the modeling skills he honed at UC San Diego to predict the most effective dosage of new therapies in development. Most recently, Boras was part of the team at Pfizer that developed the Paxlovid COVID-19 antiviral pill, the first oral antiviral treatment for COVID-19 to receive FDA emergency use authorization.

Boras shared what led him to UC San Diego, how his graduate degree prepared him for his career, and what it was like to work on such a timely and highly anticipated drug, in this Q&A.

Q: You earned a Ph.D. in bioengineering with a focus on multi-scale modeling; how and why did you choose this topic, and why at UC San Diego?

A: Between undergraduate and graduate school, I worked for several years at a small biotech company. During that time, I gained experience with computational modeling of biological systems. I really liked the ability to use mathematics and models to explain experimental results that at first seem counter-intuitive. When I applied to graduate schools, I was looking for a program that could help me expand that interest. I did a rotation in Dr. McCulloch’s lab and found a mentor and lab that balanced the experimental and the modeling sides of biology in a way that appealed to me.

Q: Where has your professional career taken you since completing your PhD?

A: After I graduated, I joined the Translational Modeling and Simulations group at Pfizer, where I have been for more than six years.

Q: Can you describe what your role at Pfizer, and on the Paxlovid team, is?

A: As the translational modeling and simulation representative on the team, my job is to use preclinical experiments (in vitro and in vivo) to try to predict what doses we should target clinically to be efficacious. We drew upon our expertise from prior Pfizer antiviral programs, in addition to HIV and HCV protease inhibitor literature and our knowledge of the SARS-CoV-2 viral PI structure to help define a target for the team.

Q: Were there any particular skills that you learned or honed during graduate school that you use regularly in your role at Pfizer?

A: Certainly, thermodynamics and mathematics skills are very useful in model construction; however, more than any particular class, the critical thinking skills that were woven throughout the entire curriculum are essential to being a good modeler. How to problem solve when you have incomplete information is one of the most valuable skills I learned. Furthermore, being able to critically evaluate your model and results or rethink the problem from a different perspective to challenge your initial assumptions is an invaluable skill that Dr. McCulloch, and the Bioengineering department as a whole, helped me learn.

Q: Whatwas it like, on a personal level, to be developing a drug with such immediate and widespread need?

A: It’s humbling. Much of my work at Pfizer has been focused on Oncology, where the road from drug discovery to observed, scalable impact on patients’ lives can take years or even a decade from when we started. To see this compound go from a molecule that showed some initially promising properties to now an authorized treatment with the potential to impact so many people around the world is inspiring. I think of all the choices the team made along the way where we could have gone in different directions that may have not led to this treatment being in the hands of patients today. It’s amazing. It’s what so many of us who go into drug development hope we can one day contribute to. I just feel so blessed to be a part of it.

Q: When you were at UC San Diego, were you involved in any organizations or groups that were meaningful to you? Or any resources that you took advantage of?

A: I was a part of the BEGS (Bioengineering graduate student) Council. I served 1 year as the Co-outreach chair. We did outreach programs like Science day at Padres Stadium, and we talked to middle school classes about science experiments. I think it’s vital to get the next generation enthusiastic about science so that they can tackle the problems they will face.

I also did intramural sports with some other bioengineering graduate students who are now some of my best friends and colleagues across bioengineering companies in San Diego. Especially given the uncertainty of the ongoing COVID-19 pandemic, these friendships have helped keep me going.

Q: What advice would you share with current students hoping to one day make an impact the way you have?

A: Find a mentor whose science appeals to you and who is interested in helping you grow and explore the area. Don’t be afraid to have conversations with professors outside the department. Some of the most interesting areas of my PhD grew out of discussions with professors outside of Bioengineering and realizing we were facing the same problem from different angles.

Finally, going back to the beginning, hone your critical thinking skills. When you generate data or a model that you are sure says one thing, take a moment to think—are there any other conclusions from the model or assumptions that would give similar results? It can help you break out of only seeing what you expect to see.

Q: Anything we didn't ask about that's important to note?

A: I was one member of a very large team aiming to meet the critical unmet need posed by COVID-19, and our work could not have advanced without our research collaborators and the clinical trial participants who bravely volunteered to be part of these studies. Communication across disciplines with chemists, biologist, pharmacologist, clinicians, and many more was essential to discovering the molecule, profiling it, and clinically testing it so that we could help people fighting this devastating disease today. I am incredibly grateful to each and every one of them.

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