Epacadostat (previously INCB24360) is an investigational drug for cancer. Epacadostat is an

inhibitor Inhibitor or inhibition may refer to: In biology * Enzyme inhibitor, a substance that binds to an enzyme and decreases the enzyme's activity * Reuptake inhibitor, a substance that increases neurotransmission by blocking the reuptake of a neurotra ...

of indoleamine 2,3-dioxygenase-1 (IDO1). Epacadostat inhibits IDO1 by competitively blocking it, without interfering with

IDO2 Ido () is a constructed language derived from Reformed Esperanto, and similarly designed with the goal of being a universal second language for people of diverse backgrounds. To function as an effective ''international auxiliary language'', ...

or tryptophan 2,3-dioxygenase (TDO). It has antitumor activity in some models, though is most effective when combined with other immunotherapy agents.

History and clinical trials

As of 2017, the combination of epacadostat with

pembrolizumab Pembrolizumab, sold under the brand name Keytruda, is a humanized antibody used in cancer immunotherapy that treats melanoma, lung cancer, head and neck cancer, Hodgkin lymphoma, stomach cancer, cervical cancer, and certain types of breast ...

(Keytruda) was being investigated by Incyte and Merck & Co. in several cancers, as was the combination of epacadostat with

nivolumab Nivolumab, sold under the brand name Opdivo, is a medication used to treat a number of types of cancer. This includes melanoma, lung cancer, malignant pleural mesothelioma, renal cell carcinoma, Hodgkin lymphoma, head and neck cancer, urothe ...

(Opdivo) by Incyte and

Bristol Myers Squibb The Bristol Myers Squibb Company (BMS) is an American multinational pharmaceutical company. Headquartered in New York City, BMS is one of the world's largest pharmaceutical companies and consistently ranks on the ''Fortune'' 500 list of the lar ...

. In April 2018, Incyte announced they were halting the Phase III ECHO-301/KEYNOTE-252 (NCT02752074) trial of epacadostat with pembrolizumab for melanoma as the combination therapy missed the first primary endpoint of improving

progression-free survival Progression-free survival (PFS) is "the length of time during and after the treatment of a disease, such as cancer, that a patient lives with the disease but it does not get worse". In oncology, PFS usually refers to situations in which a tumor is p ...

vs. pembrolizumab alone. The second primary endpoint of overall survival is not yet determined.

References

{{Chemotherapeutic agents Experimental cancer drugs Sulfamides Oxadiazoles Bromoarenes Fluoroarenes