Three drugs in the immunotherapy class have been approved by the Food and Drug Administration (FDA) to be used for treating cancer.
Assoc Prof Narin Voravud from the Chulalongkorn University Department of Medicine said the FDA had approved three drugs to be used for treating several types of cancer.
Immunotherapy is a new form of treatment that uses a patient's own immune system to help fight cancer.
Prof Narin said the drugs had been approved for the treatment of skin cancer, cancer of the large intestine, lung cancer, cancer of the bladder and cancer in the lymph nodes.
One drug approved by the FDA is used to inhibit the proliferation of cancer cells in the skin. Another drug under discussion is an immune inhibitor that is used to stop the growth of abnormal cells in the large intestine. Another is used to attack cancer cells in the lungs, bladder and lymph nodes, Dr Narin said.
The three FDA-approved drugs are administrated by injection by medical doctors, he added.
Treatment for immunotherapy can be costly but patients who were treated this way were reported to have fewer side effects than patients who receive standard chemotherapy, Dr Narin said.
Immunotherapy aims to increase the strength of immune responses against tumours. Conventional treatment for cancer targets cells, Prof Narin said.
Immunotherapy is considered effective for patients who have cancer that spreads from the part of the body it started in to other parts of the body, Prof Narin said.
He said the therapy was particularly effective with some patients in the final stages of cancer, especially those suffering from lung cancer.
Immunotherapy treatment could extend the lives of cancer patients with reduced side effects, Prof Narin said.