An early report from a large precision medicine trial of children, adolescents, and young adults with advanced cancer shows that 24% of young patients who had their tumors tested for genetic changes were eligible to receive one of the targeted therapies being tested—much higher than the 10% scientists had projected. The nationwide trial, known as NCI–COG Pediatric MATCH, is treating patients on the basis of the genetic alterations in their tumors, rather than the type of cancer or cancer site. Launched in 2017, Pediatric MATCH is one of the first large pediatric clinical trials to systematically test drugs that target specific genetic changes in cancers occurring in children, adolescents, and young adults, said NCI study chair Nita Seibel, M.D., of NCI’s Cancer Therapeutics Evaluation Program. The NCI-funded trial was developed and is led jointly by NCI and the Children’s Oncology Group (COG). Because pediatric cancers, on average, have fewer genetic changes than adult cancers, researchers were concerned about whether enough changes could be found to make a trial such as Pediatric MATCH feasible, explained COG study chair D. Williams Parsons, M.D., Ph.D., of Baylor College of Medicine. But, to date, that concern has not been borne out. “Pediatric MATCH is showing that a precision medicine approach can be studied in the pediatric setting on a large scale,” said Andrew Bukowinski, M.D., of Children’s Hospital of Pittsburgh, one of about 200 COG sites enrolling patients in the study. Dr. Parsons presented the findings at a May 15 press briefing ahead of the 2019 annual meeting of the American Clinical Society of Clinical Oncology (ASCO), being held May 31–June 4 in Chicago.