A new study published in Nature details promising results from a clinical trial using CAR-T cell therapy to treat Diffuse Intrinsic Pontine Glioma (DIPG), a devastating brain cancer that primarily affects children and young adults. The trial, led by Dr. Michelle Monje at Stanford Medicine, has shown unprecedented success, with one patient remaining tumor-free four years after diagnosis.
DIPG is a universally fatal disease with a five-year survival rate of less than 1%. The tumors are located on the brain stem, making them difficult to treat without damaging healthy cells. Traditional treatments like chemotherapy and radiation offer limited and temporary benefits.
CAR-T Cell Therapy Shows Breakthrough Results
The clinical trial involved using altered versions of the patient’s own immune cells, known as CAR-T cells, to target and kill cancer cells. The treatment initially involved delivering the CAR-T cells throughout the patient’s entire body, which caused significant side effects and required chemotherapy to deplete the patient's existing immune cells. Later, the CAR-T cells were delivered directly into the cerebrospinal fluid.
One remarkable case is Drew, a young man diagnosed with DIPG four years ago. After receiving CAR-T cell therapy, Drew has shown no evidence of disease and has returned to a normal life, attending college and pursuing his interests. According to Dr. Monje, watching him thrive reaffirms the belief that DIPG is a beatable disease.
Clinical Improvements and Challenges
In the trial, nine patients showed functional improvements, and in four, the volume of tumors was reduced by at least half. Another patient with a spinal cord diffuse glioma experienced a tumor reduction of over 90% and regained the ability to walk. However, the tumor recurred about a year after treatment, highlighting the challenges in achieving long-term remission.
Dr. Monje's team discovered that DIPG cancer cells have specific identifying markers on their surface, which allowed them to target only those cells with the CAR-T therapy. Jace Ward, one of the early patients in the trial, received multiple doses of the immunotherapy directly into his brainstem, contributing significantly to the understanding and optimization of the treatment.
Optimizing the Therapy
Researchers are still working to understand why the treatment benefits some patients more than others and why the effects are not always durable. They believe the patient’s immune system plays a crucial role and are focused on optimizing the therapy to improve its long-term effectiveness. Despite the challenges, the success of the CAR-T cell therapy offers a significant advancement in the fight against this deadly childhood cancer.
