Promising Young Scientist: Clara Libbrecht: Working ‘Bench to Bedside’ for Children

‘You want to do something in the lab that matters within your lifetime’


Clara with Drs. Loh and Sarthy Dr. Clara Libbrecht (right) discusses a lab specimen with Drs. Loh and Sarthy

Clara Libbrecht has worked at three of the leading pediatric hospitals in the United States: Children’s Hospital of Philadelphia, Boston Children’s Hospital, and, since last year, Seattle Children’s.

Spend five minutes with her and it quickly becomes clear which of the three has provided Libbrecht with the most interesting research and clinical opportunities, as well as engaging encounters with children and families: Seattle Children’s.

“It was the distinct feeling of collaboration and support I got when I interviewed here,” said Libbrecht, native of France who holds M.D. and Ph.D degrees. “I met with three different people who did lab work together. The common denominators among them were that they all were pediatric oncologists and they all worked on leukemia. I could tell they all got along well and brought out the best each other’s ideas.”

Another factor keeping Libbrecht, 37, at Seattle Children’s is working with two mentors at the Seattle Children’s Research Institute (SCRI):

  • Mignon Lee-Cheun Loh, M.D., director of the Ben Towne Center for Childhood Cancer Research and chief of the Division of Pediatric Hematology, Oncology, Bone Marrow Transplant and Cellular Therapy; and
  • Jay Sarthy, M.D. and Ph.D., a hematologist-oncologist who specializes in pediatric bone marrow transplantation for children with blood cancers and rare genetic conditions.

Sarthy is both impressed with and appreciates Libbrecht’s contributions to his lab.

“Clara brings strong research and clinical backgrounds, plus her interest is in a leukemia subtype that we had not previously focused on – mixed phenotype acute leukemias,” said Sarthy. “These are thought to be driven by epigenomic dysfunction, but are generally poorly characterized and can be quite difficult to treat, thereby providing great research and clinical opportunities.”

Those opportunities are vital to Libbrecht’s professional goal – working “bench to bedside” to help address pediatric leukemia. She and her colleagues face a daunting challenge.

According to the American Cancer Society, Leukemia is the most common cancer in children and teens, and accounts for nearly one in three cancers. Approximately 75 percent of leukemia cases among children and teenagers are acute lymphocytic leukemia (ALL). The remaining 25 percent are acute myeloid leukemia (AML). The 5-year survival rate for children with ALL is about 90 percent overall; with AML it ranges from 65 to 70 percent.

“You want to do something in the lab that matters within your lifetime, that matters to children and their families,” she said.

It is also apparent that she is committed to pediatrics.

“For children, being sick and being treated in a hospital, and not being in school, changes their everyday lives,” Libbrecht said. “But once they feel better, children are running in the hallways and having fun because they are kids. It’s who they are. Children are so resilient.”

Resilience and determination also characterize Libbrecht’s cross-Atlantic academic journey.

That journey began 20 years ago when she entered Université René Descartes in Paris. After being awarded a medical degree in 2010, she embarked on a four-year pediatric residency in Lyon, France. That was followed by relocating to Colorado for a Master’s Degree in Oncology at the University of Colorado.

“That one year of research in Colorado enabled me to sit down and have time to think,” Libbrecht said. “You are taught in medical school that, ‘If the patient has this disease, they receive this treatment.’ But there is no time to think about the molecular reasons behind the disease, I went back to France because I missed seeing patients, but found myself still not having time to think about my patients.”

She returned to Lyon in 2015 as a Clinical Fellow in Pediatric Hematology and Oncology but ultimately decided to go back to the bench and moved to Philadelphia where she completed her Ph.D. at Children’s Hospital of Philadelphia in molecular biology from 2016 to 2020. Later that year, she moved to Boston for a pediatrics residency program.

In 2023, she joined the Ben Towne Center for Childhood Cancer Research at SCRI and UW Medicine as a Fellow in the Division of Pediatric Hematology-Oncology. Such a diverse background also impressed Sarthy.

“I did not select Clara for my lab as much as tried very hard to show her the cool projects we work on and hoped that she would join,” he said. “She has a tremendous background in pediatric leukemia epigenetics, and as such is a perfect fit for the lab. Moreover, Clara pays attention to data and has a desire to develop rigorous models. She is also fun to work with and genuinely interested in learning new methods.”