Better delivering cytokines for cancer therapy

In 2013, the journal Science chose cancer immunotherapy as the breakthrough of the year, largely due to the impact of checkpoint inhibitors. Interleukin-2 (IL-2), a cytokine, also played a part. In addition to IL-2, interferon-gamma (IFN-g), and interleukin-12 (IL-12) have come to prominence in recent years. However, toxicity limits their use. Can this be overcome?