Innovative Fusion Protein Enhances Cancer Immunotherapy Effectiveness

Scientists at the University of Basel and University Hospital Basel have developed a groundbreaking fusion protein that combines two potent immunotherapy strategies to fight cancer more effectively. This novel molecule simultaneously blocks the 'do not attack' signals employed by tumors and specifically activates immune cells responsible for tumor destruction. This dual mechanism aims to increase the efficacy of cancer treatments while potentially reducing adverse side effects.

The fusion protein integrates an IL-2 variant (IL-2v), which is designed to activate immune cells that target and kill cancer cells, with an antibody targeting PD-1—a receptor highly expressed on immune cells within the tumor microenvironment. Researchers tested this combination on lung cancer patient samples and found that it selectively stimulates immune cells infiltrating the tumor, boosting their cancer-fighting activity. Notably, it reactivates exhausted immune cells that have been rendered inactive due to chronic tumor exposure.

This approach offers dual benefits: the antibody component directs IL-2v precisely to the tumor site, ensuring targeted immune activation, while also blocking the PD-1 pathway that tumors exploit to evade immune responses. This effectively releases the immune system's brakes, allowing a more robust attack on the cancer.

Currently, this fusion protein is being evaluated in a phase I clinical trial led by Roche. The findings point to a promising future for cancer immunotherapy, emphasizing enhanced immune activation with potentially lower side effects. This development marks a significant step forward in personalized cancer treatment strategies.

Source: https://medicalxpress.com/news/2025-09-stronger-fusion-protein-boosts-cancer.html