Table of Contents
- What is Epacadostat?
- How Epacadostat Works
- Cancers Treated with Epacadostat
- Epacadostat in Combination Therapy
- How Epacadostat is Administered
- Potential Side Effects
- Ongoing Research and Future Prospects
What is Epacadostat?
Epacadostat is an innovative drug being studied for the treatment of various types of cancer. It is also known by its alternative names INCB024360 and IDO1 inhibitor[1]. Epacadostat belongs to a class of drugs called immunotherapy, which works by helping your body’s immune system fight cancer cells[2].
How Epacadostat Works
Epacadostat works by blocking an enzyme called IDO1 (indoleamine 2,3-dioxygenase 1). This enzyme is often overactive in cancer cells and helps them hide from the immune system. By blocking IDO1, epacadostat may allow the immune system to recognize and attack cancer cells more effectively[2][1].
Cancers Treated with Epacadostat
Epacadostat is being studied in clinical trials for various types of cancer, including:
- Thymic carcinoma: A rare cancer that starts in the thymus gland[3]
- Non-small cell lung cancer (NSCLC): A common type of lung cancer[4]
- Urothelial carcinoma: A type of bladder cancer[4]
- Gastrointestinal stromal tumors (GIST): A type of tumor that occurs in the digestive tract[5]
- Pancreatic cancer[6]
- Head and neck squamous cell carcinoma (HNSCC)[7]
- Nasopharyngeal cancer: A type of cancer that starts in the upper part of the throat behind the nose[8]
- Myelodysplastic syndromes (MDS): A group of blood disorders where the bone marrow doesn’t produce enough healthy blood cells[1]
Epacadostat in Combination Therapy
Many clinical trials are studying epacadostat in combination with other immunotherapy drugs, particularly those that target PD-1 or PD-L1 proteins. These combinations include:
- Epacadostat + Pembrolizumab (Keytruda): This combination is being studied in thymic carcinoma, GIST, and head and neck cancer[3][5][7]
- Epacadostat + Atezolizumab (MPDL3280A): Being studied in NSCLC and urothelial carcinoma[4]
- Epacadostat + Durvalumab: Being studied in nasopharyngeal cancer[8]
- Epacadostat + Sirolimus: Being studied in advanced solid tumors[9]
The idea behind these combinations is that they may work better together to stimulate the immune system against cancer than either drug alone.
How Epacadostat is Administered
Epacadostat is typically taken orally (by mouth) in the form of tablets. The dosage and frequency can vary depending on the specific clinical trial and the type of cancer being treated. Some common dosing schedules include:
It’s important to note that the optimal dosage is still being determined through clinical trials.
Potential Side Effects
As with any medication, epacadostat can cause side effects. The full range of side effects is still being studied in clinical trials. Some potential side effects may include fatigue, nausea, and changes in blood cell counts. When used in combination with other immunotherapy drugs, there may be additional side effects related to the immune system becoming overactive[7][8].
Ongoing Research and Future Prospects
Epacadostat is still considered an experimental drug and is not yet approved for general use outside of clinical trials. Researchers are conducting various studies to determine its effectiveness, optimal dosing, and potential side effects. Some areas of ongoing research include:
- Using epacadostat before surgery (neoadjuvant therapy) in head and neck cancer[7]
- Studying epacadostat’s effects on the immune system and tumor microenvironment[10]
- Investigating biomarkers that might predict which patients will respond best to epacadostat treatment[7]
The results of these ongoing clinical trials will help determine the future role of epacadostat in cancer treatment. While early results are promising in some cancers, more research is needed to fully understand its benefits and risks.



