Immunotherapy is a blossoming field that is becoming more
advanced. Instead of other treatments that kill healthy cells in addition to
killing cancerous cells, immunotherapy uses the body’s immune system to fight
cancer cells, leaving healthy non-cancerous cells intact. It is a better
treatment because it is very effective, more efficient, and is easier on the
body. There are four main types of
immunotherapy including monoclonal antibodies, immune checkpoint inhibitors,
cancer vaccines, and other non-specific types of immunotherapy.
A supplemental cancer treatment using immunotherapy may
become available for treating mesothelioma. While not currently approved for
the use of mesothelioma, it is approved for other types of cancer and is
showing promising results. Dendritic cell therapy is a type of immunotherapy
that utilizes special immune cells called dendritic cells that help the body’s
immune system locate cancer cells. These cells do this by showing other cells antigens
(substances that initiate the immune response) that are on the surface of
different substances. Dendritic cells break down cancer cells and show the
cancer cells’ antigens to other cells in the body so any cells with the
antigens can be attacked. The therapy is done so by creating a vaccine from the
patient’s own immune cells. They are extracted and exposed to cancer cells or
other antigens and then exposed to chemicals that turn the cells into dendritic
cells. They are then injected back into the patient where they are able to
attack the specific cancer cells they were meant to attack.
The Study is randomized 1:1 where half of the patients will
be receiving the MesoPher Dentritic Cell Treatment while the other half will be
treated for their mesothelioma normally. Between 9 and 13 weeks after patients
are done with their last cycle of chemotherapy,
five doses of the MesoPher will be injected on days 1, 15, 29, and weeks
18 and 30. If there are no adverse effects including the acceleration of cancer,
a patient reacting badly to the treatment, or withdrawal symptoms the study
will be continued. The study started in
May 2018 and will take a total of three years to complete. To create the
dendritic cells, blood is extracted from each patient and the monocytes, a type
of white blood cell, are isolated from the blood. They are then loaded with
PheraLys, which is the treatment, and then injected back into the patient’s
body. The cells are then able to show the immune system the antigens, and the
cells are able to attack the tumor.
This is unlike Keytruda, which is an immune checkpoint
inhibitor. Keytruda is already used for melanoma, non-small cell lung cancer,
and head and neck squamous cell cancer. It works by blocking the PD-1 protein,
which allows cancer cells to hide from the immune system and continue
spreading. If the protein is blocked, the immune system can pinpoint rogue
cancer cells and attack and kill them.
There is no cure for mesothelioma but new medical
advancements continue to be developed. Clinical trials have to be continued for
this to happen.
Sources:
“Amphera presents data of MesoPher and checkpoint inhibitor
combination therapy to treat mesothelioma at AACR 2019” Amphera April 4, 2019).
[Link]
Robert A. Belderbos, “A multicenter, randomized, phase II/III study of dendritic cells loaded with allogeneic tumor cell lysate (MesoPher) in subjects with mesothelioma as maintenance therapy after chemotherapy: DENdritic cell Immunotherapy for Mesothelioma (DENIM) trial” Translational Lung Cancer Research (June 2019). [Link]