A new class of cancer therapy is emerging, promising both precision and power with fewer side effects. Researchers from the University of Basel and University Hospital Basel, Switzerland, in collaboration with Roche, have developed a fusion protein that unites two potent immunotherapy strategies in a single treatment.
This novel molecule works by combining a modified version of interleukin-2 (IL-2v) with an antibody that targets PD-1, a receptor found on immune cells in tumors. While traditional IL-2 therapy was a landmark in immunotherapy—first used successfully in 1984 when Dr. Stephen Rosenberg cured Linda Taylor of advanced skin cancer—it often led to severe side effects and, paradoxically, activated suppressive immune cells.
The new fusion protein addresses these limitations. The PD-1 antibody component guides IL-2v directly to the tumor, ensuring only cancer-fighting immune cells are activated. Simultaneously, it blocks the PD-1 pathway, which cancer cells exploit to evade attack. This two-pronged action both reawakens exhausted immune cells and prevents immune suppression within the tumor microenvironment.
In laboratory studies using immune and cancer cells from lung cancer patients, the therapy selectively activated tumor-killing immune cells while avoiding the harmful stimulation of regulatory T cells. The result: a sharper, more controlled immune response against cancer.
By blending precise targeting with immune system activation, this dual-action fusion protein could pave the way for safer and more effective cancer immunotherapies, representing the next evolution of a journey that began with IL-2 four decades ago.