Advances in cancer immunotherapy have helped scientists better understand the immune system, such as the development of checkpoint inhibitors, which are medicines that are effective at shrinking numerous types of tumors, including melanoma and certain solid tumors. However, the unpredictability of the efficacy of checkpoint inhibitors led researchers to search for companion molecules that could bolster the checkpoint inhibitors’ impact.

Since 2014, the number of clinical studies combining checkpoint inhibitors with other molecules has skyrocketed, from 58 in 2014 to 469 in 2017. Although companies developing experimental immunotherapies have drawn great interest from investors, the immunotherapy space remains a high stakes sector. To address this, companies have spent billions of R&D dollars on discovering immuno-oncology drugs that can improve the effect of checkpoint inhibitors by helping the immune system block proteins used by tumors to impede the immune system, molecules that strengthen the immune system and drugs that can change the environment surrounding a tumor to make it more vulnerable to T-cell attack.

So far, 6 checkpoint inhibitors have been approved by the FDA for cancers including melanoma, lung, kidney, bladder, gastric, head and neck, Hodgkin’s lymphoma, and Merkel cell carcinoma.

Source: C&EN