The IL-2 cancer pipeline remains deep, diverse

The late-stage failure this week of Nektar’s IL-2 program once again highlights the longstanding challenge of harnessing IL-2 as a cancer immunotherapy, even when the cytokine is engineered to avoid inflammatory side effects. But the IL-2 pipeline remains deep and diverse, spanning at least four modalities plus new approaches to selectively target IL-2 to the tumor or to immune cell subsets. 

Recombinant IL-2 was a cancer immunotherapy long before the advent of checkpoint inhibitors, but the cytokine saw limited use because the inflammation it induces can cause toxic vascular leakage. And while IL-2 works by stimulating effector T cells, it can also activate immunosuppressive regulatory T (Treg) cells, undermining its own efficacy...