A two-armed antibody slowed three kinds of mouse tumour. No patient has had it.
A CCR8xCD3 antibody depleted tumour regulatory T cells in mice and in human samples. Science Translational Medicine, 28 October 2026. No patient data.
Regulatory T cells inside a tumour tell the rest of the immune system to stand down. Many of them carry a receptor called CCR8. Antibodies that try to remove them usually need natural killer cells, and some tumours have few of those.
A paper in Science Translational Medicine on 28 October 2026 describes a bispecific antibody that binds CCR8 and CD3, so ordinary T cells do the killing. In human tumour samples it depleted the CCR8-positive regulatory cells. In mice it slowed breast, lung, and colon tumours, alone and with a checkpoint drug. Monkeys tolerated it without cytokine release syndrome.
Key Facts
- Science Translational Medicine, 28 October 2026, doi:10.1126/scitranslmed.aea7127.
- CCR8xCD3 T-cell-engaging bispecific antibody.
- Depleted CCR8-positive regulatory T cells in human tumour samples.
- Slowed breast, lung, and colon tumours in mice, alone and with anti-PD-L1.
- Cynomolgus monkeys tolerated it. No cytokine release syndrome reported.
Why This Matters
Checkpoint drugs fail in tumours that are full of regulatory T cells. A way to remove those cells that does not depend on scarce natural killer cells is a real design change. It is still a design.
What We Don't Know Yet
No person has been treated. The human dose is unknown. Whether cytokine release appears in people, when it did not in monkeys, is unknown. Which tumours have enough CCR8-positive cells for this to matter is unknown. Bispecific T-cell engagers have a known cytokine risk even when a monkey study is quiet.
Sources: EurekAlert / AAAS · Science Translational Medicine, 28 October 2026