Advances in immunotherapy
Among the completely reassuring things scientists wish you knew about cancer is the progress being made to eradicate this disease, in which abnormal cells multiply and take over in the body. Last year there were over 1,685,000 cases of cancer diagnosed, and nearly 600,000 people died. Standard therapies so far have included surgery, radiation to kill the cells, and chemotherapy, which alters the DNA of cancer cells to stop them from reproducing. But radiation and chemo damage healthy cells too, so researchers have been looking for better treatments. New immunotherapy drugs use the patient’s own immune cells to attack cancer. Stephen Hunger, MD, chief of the Division of Oncology, chief of the Division of Pediatric Oncology, and director of the Center for Childhood Cancer Research at Children’s Hospital of Philadelphia, tells us about two of the exciting immunotherapy treatments approved this year: “Inotuzumab uses an antibody to recognize leukemia cells and deliver a toxin selectively to these cells, thereby killing them with many fewer side effects than seen with standard chemotherapy drugs,” Dr. Hunger says. Another effective new therapy is a drug called blinatumomab. “This drug essentially acts as a link to bring T-cells into contact with malignant B-cells, enabling them to kill the leukemia cells,” he says.
First-ever gene therapy
The biggest cancer breakthrough of the year is FDA approval of the first gene therapy drug, developed at CHOP and the University of Pennsylvania to treat young people with acute lymphoblastic leukemia (ALL) when all other treatments have failed. “CAR T-cell therapy involves removing healthy T-cells from a patient’s body and genetically modifying them,” Dr. Hunger says. After they’ve been reprogrammed to identify cancer, “these cells are then re-infused into the patient and they travel throughout the body and find the [cancer] cells, attack, and kill them.” The T-cells also reproduce to work long-term. Dr. Hunger calls the results “remarkably effective:” In clinical trials, 83 percent of patients went into remission within three months, with about half remaining healthy two years later. “This is also quite remarkable, as less than 10 to 20 percent of children with relapsed or refractory ALL are alive after two years with standard therapies,” Dr. Hunger says. There are some side effects, such as high fever, so more work needs to be done. “New efforts are directed to understanding how physicians can integrate this into the ‘toolbox’ of therapies they use for children, adolescents, and young adults with ALL,” he says.