The pediatric plenary on Feb. 12 will delve into the dynamics of a particularly vulnerable and understudied population that undergoes stem cell transplant — infants and toddlers — with a focus on reducing the toxicity of conditioning regimens and transplant in general without compromising overall survival. Plenary: Stem Cell Transplant Approaches in Infants – Not Just Really, Really Young Adults will begin at 8:10 a.m. in Room 313 ABC.

“Much of what we know from the literature, from adults or even older children, is not necessarily the same in this cohort, and the diversity of pathology that we see in this young age group is perhaps the most unique of any age group,” said Session Chair Miki Nishitani, MD, a clinical instructor at Harvard Medical School and an attending physician at Dana-Farber/Boston Children’s Cancer and Blood Disorders Center.

“Infants are at particular risk for certain acute and long-term toxicities, and many people are investigating various approaches to reducing some of these,” Nishitani continued. “If we can improve overall survival and event-free survival while also reducing these toxicities, that would be the best-case scenario. There’s also a lot of movement toward increasing the use of stem cell transplant and cellular therapies for infants with rare immunodeficiencies and metabolic disorders that are being screened for more frequently, so as we detect more of these patients who are eligible for transplant, thinking about how we reduce toxicities for these kids is really important.”

To compound the challenges of establishing effective therapies for children younger than 3 years who undergo stem cell transplant, many of the diseases treated through transplant are so rare that large randomized controlled trials are nearly impossible to conduct on a timely basis to be able to produce results that can be acted upon effectively.

“A lot of the research done on the approaches for stem cell transplant on these rare diseases takes years to conduct, and infants, while they’re prone to having a tough transplant course and may be at higher risk for certain complications, they’re also a pretty resilient group of patients,” Nishitani said. “That makes us as clinician scientists pretty determined to work toward improving their overall morbidity and mortality. That’s what I hope people get out of this session.”

Nishitani will open the plenary with a presentation on developmental impacts of transplant in infants.

Christopher Dvorak, MD, professor of pediatrics and chief of the Pediatric Allergy, Immunology and Bone Marrow Transplant Division at the University of California, San Francisco, Benioff Children’s Hospital, and Janel Long-Boyle, PharmD, PhD, professor in the Department of Clinical Pharmacy at the University of California, San Francisco, will discuss conditioning exposure in infants in a joint presentation.

“They both have done a tremendous amount of work looking into the pharmacokinetics of various conditioning drugs,” Nishitani explained. “Infants and toddlers metabolize these drugs very differently than adults, so learning about the pharmacokinetics of these drugs and how this can affect both acute and long-term toxicities of transplant in these kiddos is critical.”

Ashish Gupta, MBBS, MPH, associate professor in the Division of Pediatric Blood and Marrow Transplantation & Cellular Therapy at the University of Minnesota, will review the optimal timing for stem cell transplant in infants with genetic disorders. He is an expert in transplant for metabolic disorders.

Hisham Abdel-Azim, MD, chief of transplant/cellular therapy at Loma Linda University School of Medicine, Cancer Center, Children Hospital and Medical Center, will provide new insights into the outcomes in children from the EndRAD Trial, an ongoing clinical trial aimed at eliminating total body irradiation (TBI) in patients with B-cell acute lymphoblastic leukemia (B-ALL) who come into transplant with negative disease burden.

Sharing a European perspective on treatment of pediatric patients with cancer, Christina Peters, MD, will discuss TBI use in children with ALL. She is a professor of pediatrics in the Department of Stem Cell Transplantation at St. Anna Children’s Hospital, Vienna, Austria. TBI can result in late effects such as neurocognitive delay, developmental delay, endocrinology, and secondary cancers, prompting researchers to seek treatment strategies that reduce the dose of TBI or eliminate it.

“Ultimately, it would be a dream to see a world in which the field ultimately eliminates TBI from these regimens, if at all possible,” Nishitani said. “TBI is a pretty significant risk factor for various types of late effects, especially in this younger cohort whose organs are still developing and at a very fast rate.”

This and other sessions at the 2025 Tandem Meetings | Transplantation & Cellular Therapy Meetings of ASTCT® and CIBMTR® will be available for on-demand viewing for registered attendees following the live presentation.