The New Immunotherapy of Cancer

For the treatment of cancer so far, all we have had in the past is chemotherapy, which attacks all rapidly multiplying cells in the body.  Examples of this are the hair follicles, the skin, the mucosa of the bowel, and the immune system itself, which is supposed to weed out the cancer cells as they appear.  This leads to hair loss, sallow skin, diarrhea, vomiting, and may predispose to other cancers down the road.  But in the last ten years, the immunotherapy of cancer has come into its own.  So much so, in fact, that the days of chemotherapy are numbered and the prediction is that it will be replaced by immunotherapy, except as adjunctive to other forms of treatment.

The new form of cancer therapy is available in one of three forms: 1) Checkpoint inhibitor antagonists 2) monoclonal antibodies against the cancer cells themselves 3) Adoptive therapies.

Checkpoint inhibitor antagonists

The programmed death cell receptor (PD-1) on the surface of the various cells in the body pre-programs them for natural death (apoptosis).  The programmed death cell ligands (PD L-1 and PD L-2), which bind to these receptors allow the cells to live beyond their life expectancies and to accumulate.  The drugs that are directed against these inhibitors of cell death that are already approved by the FDA include Opdivo (nivolumab), Keytruda (pembrolizumab), and Tenectriq (atelizumab).  These are monoclonal antibodies that prevent the effect of PD L-1.  One of them is the agent that induced the remission of former President Jimmy Carter’s metastatic malignant melanoma.

Monoclonal antibodies against cancer cells

The monoclonal antibodies directed against the cancer cells themselves that are approved by the FDA and that are already available include Avastin (bevacizumab) and Cyramza (ramucirumab).  Still under study is at the last inspection is patrizumab (NCT02133196).

Adoptive cell therapies

The adoptive cell therapies involve drawing blood from the patient with cancer, fractionating the different cells, and extracting the T-cells layer.  The T-cells are then treated in the test tube to make them more reactive to the cancer cells, and re-infusing them into the patient.  One of the study drugs that is used to activate the T-cells goes by the designation of NCT02133196.

To these new forms of immunotherapy of cancer may be added the inhibitors of angiogenesis, which prevent the development of blood vessels and thus deprive the cancer of essential nutrients that it needs to keep on growing.  These inhibitors of angiogenesis may be used alone or in combination with one of the immunotherapy agents.

Caution

These new medications are very expensive and, without medical insurance, cost prohibitive. The research medications are not only free, but patients are often paid for participation in the studies.

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