In 2021, Alyssa, who is now thirteen years old, and her family were told that she had acute lymphoblastic leukemia. Alyssa did not respond to either the standard leukemia treatment or a subsequent bone marrow transplant.
Her oncology team opted to enroll Alyssa in a clinical trial at GOSH children’s hospital in London. She became the first patient to receive a new treatment that uses immune cells from a healthy donor that were genetically engineered.
The results? Alyssa’s treatment-resistant leukemia went into remission within one month.
About Alyssa’s Recovery
The success of the first transplant paved the way for a second bone marrow transplant intended to restore Alyssa’s immune system. She returned to her home in Leicester, England shortly thereafter where she received follow-up care and monitoring.
About Acute Lymphoblastic Leukemia (ALL)
ALL affects immune system cells (T-cells and D-cells), primarily among children. T-cells are normally responsible for attacking cancerous cells as evidenced in 2015 when GOSH researchers first used genome-edited T-cells in the treatment of B-cell leukemia.
However, in order to treat other forms of leukemia, the GOSH team found that they were facing a challenge during the manufacturing process: the T-cells were destroying each other.
About Base Editing
Base editing of T-cells requires the chemical conversion of DNA code letters that carry instructions for certain proteins. Base editing enables scientists to produce precise, single-letter modifications to DNA. The changes to the base editing cells are necessary in order to target only cancerous cells.
Base editing is still in its early stages. Although its side effects following infusion are manageable, they can be quite severe.
Alyssa was given the bone marrow transplant because her T-cell response was wiped out for several weeks, making her vulnerable to new or previous viruses.
Waseem Qasim, an immunologist at GOSH, said that the new cell engineering bodes well for other diseases. Currently, two children are being evaluated as the next patients to be treated with T-ALL therapy.
Alyssa and her mother hope the advancement in therapy will bring about brighter futures for other patients.
