The U.S. Food and Drug Administration last week granted breakthrough therapy designation for the MEK 1/2 inhibitor selumetinib. The designation is for the treatment of pediatric patients aged three years and older with neurofibromatosis type 1 (NF1) symptomatic and/or progressive, inoperable plexiform neurofibromas (PN), a rare, incurable genetic condition.
Breakthrough therapy designation is designed to expedite the development and review of drugs intended to treat a serious condition where preliminary clinical evidence indicates the drug may demonstrate substantial improvement over available therapy.
The designation is based on phase II data from the multicenter SPRINT trial of selumetinib for children with NF1 and plexiform neurofibromas, led by the Center for Cancer Research Pediatric Oncology Branch (POB) Chief Brigitte Widemann, M.D. In addition to observing tumor shrinkage in 74 percent of patients, who had a partial response, the researchers found that selumetinib led to improvements in clinical outcomes such as pain, strength and quality of life. Early trial results were presented at the 2018 American Society of Clinical Oncology Annual Meeting by POB Assistant Research Physician Andrea Gross, M.D.
The multicenter phase II clinical trial, which included 50 patients, is sponsored by NCI’s Cancer Therapy Evaluation Program and conducted via a Cooperative Research and Development Agreement with AstraZeneca, who are in collaboration to develop selumetinib. Conducted at the NIH Clinical Center and other participating sites, the study took advantage of techniques developed by Dr. Widemann’s team that enabled very precise measurement of the plexiform neurofibromas.