Former President Jimmy Carter, who died Sunday, Dec. 29, at age 100, lived for nearly a decade after being treated with a breakthrough cancer drug developed at UCLA Health.
The treatment co-developed by Antoni Ribas, MD, PhD, a professor of medicine at the David Geffen School of Medicine at UCLA, helped extend President Carter’s life and allowed him to maintain his busy schedule. President Carter, a Nobel Prize winner and lifelong human-rights activist, was able to continue painting, writing books, teaching Sunday school, volunteering with Habitat for Humanity and remaining a prominent public figure well into his 90s.
After receiving the 2015 diagnosis of metastatic melanoma — the deadliest and most aggressive form of skin cancer — President Carter was treated with the immunotherapy drug pembrolizumab (Keytruda), a groundbreaking shift in the treatment of melanoma and other malignant cancers.
Dr. Ribas, director of the Tumor Immunology Program at the UCLA Health Jonsson Comprehensive Cancer Center, led the international research team that reported pembrolizumab’s effectiveness in patients with melanoma.
The treatment “unleashes the immune response to recognize and fight cancer,” Dr. Ribas says. Because tumor cells start off as healthy cells before becoming malignant, they don’t naturally stimulate the same immune response as a foreign invader (like a virus or bacteria) would. The immune system is regulated by checks and balances to prevent it from attacking normal organs. Pembrolizumab overrides these regulators so the body can use its own immune forces to fight cancerous cells.
“When this is achieved, patients with a cancer that’s spread through the body can have responses that last for years,” Dr. Ribas says. “The immune system has the ability to travel around the body and find cancer cells anywhere, and then has memory — which leads to long-term responses.”
Few treatments existed for metastatic melanoma before the discovery of this intervention. There are now six FDA-approved immunotherapy drugs available that are proving successful in treating more than 30 different cancers, including some lung cancers and Hodgkin’s lymphoma.
Dr. Ribas received National Cancer Institute Outstanding Investigator Awards in 2015 and 2022 for this research. The $8.4 million award continues to fund exploration of immunotherapies and cancer treatments.
In 2020, Dr. Ribas was elected to the National Academy of Medicine, which honors individuals for outstanding professional achievement and contributions to the advancement of medical science, for his work in defining how patients respond to immunotherapies and for his work in developing pembrolizumab.
Before these immunotherapy advances, only about one in 20 patients with advanced melanoma could be treated, Dr. Ribas says, because the disease doesn’t typically respond to chemotherapy and radiation. With the discovery of drugs such as pembrolizumab, one in two patients with advanced melanoma can now be effectively treated.
“But 40 to 50 percent is not good enough,” Dr. Ribas says.
His team is studying how patients respond to immunotherapies and uncovering genetic elements that inhibit the immune response. They’re also experimenting with new drug combinations that bolster the immune system.
When Dr. Ribas began studying immunology and melanoma 25 years ago, most people didn’t believe the immune system could be used to fight cancer. “Some people even laughed at the idea,” he says.
Increased understanding of immunology, however, has created a whole new pillar of cancer treatment — immunotherapy – which is now the first line of attack for many diagnoses.
“It’s harnessing what nature developed for our body to protect from outside invaders to redirect to an inside invader, which is cancer,” Dr. Ribas says.
