Branden Baptiste, a 20-year-old man who suffered from severe sickle cell disease, has become the first patient in the world to be successfully treated with base editing, a highly precise form of gene therapy. The experimental treatment, part of the BEACON trial led by doctors at Boston Children's Hospital and sponsored by Beam Therapeutics, has allowed Baptiste to live a normal, pain-free life.
A Life Transformed
For years, Baptiste endured frequent sickle cell crises, resulting in hospitalizations, severe pain, and multiple complications, including hip replacements and acute chest syndrome (ACS). "From age 12, things skyrocketed," Baptiste recalled, noting he missed approximately 60 days of school each year due to his condition. By 17, he had suffered life-threatening ACS episodes, leading to a significant decline in his quality of life.
According to Matthew Heeney, MD, Baptiste’s hematologist at Boston Children’s Hospital, Baptiste had developed several chronic complications, including organ dysfunction affecting his kidneys, lungs, joints, and eyes. Gene therapy emerged as a potential curative option.
The BEACON Trial and Base Editing
Heeney offered Baptiste two gene therapy options: the GRASP trial and the BEACON trial. Baptiste chose the BEACON trial, which utilizes base editing to boost fetal hemoglobin production. Unlike traditional gene editing methods that cut or break DNA strands, base editing uses enzymes to correct single “misspelled letters” within a gene. This precise approach minimizes the risk of off-target effects.
Branden underwent a series of tests to ensure he could withstand the treatment. In October 2023, doctors collected his blood stem cells, which were then sent to a specialized facility for base editing. Before receiving the edited cells, Branden underwent chemotherapy to eliminate the diseased stem cells in his bone marrow.
Recovery and Future Prospects
Branden received his base-edited cells in December 2023 and was discharged from the hospital ahead of schedule on Christmas Eve. Since the treatment, he has been off all sickle cell medications and reports feeling better than ever. "In my opinion, I’m perfect," Baptiste stated. "I never felt fine before—before, ‘fine’ was moderate pain I could take deep breaths through. Now I’m more than fine. I’m operating in every way possible."
Baptiste has since finished high school, secured a job at the Transportation Security Administration (TSA), and started exercising regularly. Early results from the BEACON trial, presented at the American Society of Hematology Annual Meeting, indicate that base editing is safe, increases fetal hemoglobin levels, and reduces anemia.
"The treatment has been truly transformative for Branden," Heeney said. "Not only are his blood counts and markers of disease activity essentially normalized, but he can now complete daily activities that most take for granted and tackle new experiences previously beyond his reach. It is a joy to see him setting goals that seemed unfathomable just a year or two ago."
Branden will continue to be monitored for the next 15 years by Boston Children’s Gene Therapy Program. The BEACON trial is ongoing, offering hope for other individuals with sickle cell disease.
