Cancer Immunotherapy Shows Striking Results While New Research Tackles Heart Risks

A redesigned cancer immunotherapy triggered whole-body tumor destruction in early trials, shrinking cancers in half of patients and wiping them out entirely in two. Results from the phase 1 clinical trial of the modified drug, called 2141-V11, have been published in the journal Cancer Cell.

Among the 12 participants in the study, tumors shrank in six patients. Two of those patients experienced complete remission, meaning their cancers disappeared entirely. The trial involved people with several types of metastatic cancer, including melanoma, renal cell carcinoma, and different forms of breast cancer.

Researchers observed something unusual: the treatment did not only affect the tumors that were injected with the drug. Tumors located elsewhere in the body also shrank or were eliminated by immune cells. One melanoma patient had dozens of metastatic tumors on her leg and foot. After multiple injections of just one tumor on her thigh, all the other tumors disappeared.

The drug is an engineered CD40 agonist antibody developed by researchers at Rockefeller University. CD40 is a receptor found on the surface of certain immune cells. When CD40 is activated, it signals the immune system to mount a stronger response, helping trigger anti-tumor immunity and generate cancer-targeting T cells.

In 2018, the team engineered the antibody 2141-V11 with support from Rockefeller's Therapeutic Development Fund, founded by trustee Julian Robertson and continued by the Black Family Foundation. The redesigned antibody binds tightly to human CD40 receptors and was modified to improve crosslinking by interacting with a specific Fc receptor. Laboratory studies showed the new design was about 10 times more effective at triggering an immune attack against tumors.

Researchers also changed how the drug was delivered. Traditionally, CD40 therapies were given through intravenous infusion. Because CD40 receptors exist throughout the body, many healthy cells would absorb the drug, leading to toxic side effects. Instead, the team injected the treatment directly into tumors. None of the participants in the trial experienced the severe side effects previously associated with CD40 drugs, such as widespread inflammation, dangerously low platelet levels, and liver damage.

The two patients whose cancer vanished had melanoma and breast cancer, respectively. Both cancers are known for being aggressive and prone to recurrence.

Meanwhile, separate research has identified a way to dramatically reduce heart risks associated with immune checkpoint inhibitors (ICIs), treatments that have revolutionized cancer care since 2011. Scientists at Cincinnati Children's published their findings February 20, 2026, in the Journal of Experimental Medicine.

Immune checkpoint inhibitors work by cutting off signals from "checkpoint" proteins that cancer cells use to hide from the immune system. This allows the body's T cells to recognize and destroy tumor cells. However, in about 2% of all cancer patients receiving ICIs, the treatments can cause myocarditis—an inflammation of heart muscle. About half of these patients die from this complication, even if they survive their cancer.

The research team engineered a new mouse model that accurately mimics immune checkpoint inhibitor–induced myocarditis. In a series of advanced experiments, the team pinpointed a key driver of the complication: CD8 T cell–derived tumor necrosis factor (TNF).

The team found that this complication from checkpoint inhibitors is not caused by tumors exhausting the body's cancer-specific T cells, but rather through causing new production of "autoreactive" T cells that see healthy cardiac muscle cells as targets in addition to cancer cells.

The team showed, in mice, that blocking TNF signaling specifically through the TNFR2 gene product prevented the inflammatory cycle from starting in the heart. Checkpoint inhibitors allow TNF signaling to trigger CD8 T-cells that are specific to antigens on cardiac myocytes, which in turn leads to life-threatening arrhythmias. The targeted TNF blockade method prevented this cycle in mouse models.

More research is needed to determine if a narrowly focused TNF inhibitor would be safe for human use, and how long a patient might need to take such a drug. TNFR2-specific antibodies remain in development stages. The team also wants to determine whether similar approaches can also prevent immune-related adverse events affecting other organs.