What's New in Chronic Lymphocytic Leukemia (CLL) Research?

Research on chronic lymphocytic leukemia (CLL) is being done in many medical centers and other institutions around the world. Each year, scientists find out more about what causes the disease, how to test for it, and how to better treat it.

Most experts agree that treatment in a clinical trial should be considered for any person with CLL. This way, people can get the best treatment available now and may also get the new treatments that are thought to be even better.

Some of the new and promising treatments discussed here are only available in clinical trials.

Research into the genetics of CLL

Scientists are learning a lot about the gene and chromosome changes inside CLL cells that make them different from normal cells and how these changes affect their growth and responses to different treatments.

This type of information is being used to help doctors know when treatment needs to be started, which treatments are most likely to work, and what a person's long-term outlook is likely to be.

It's also changing the way CLL is treated. In recent years, newer targeted drugs that focus on some of these gene changes have changed the way CLL is treated (see below).

Researching new medicines for CLL

At one time, chemotherapy (chemo) was the main treatment for CLL, but newer types of medicines have largely replaced it. These medicines tend to work better and often have fewer side effects than chemo.

Targeted drugs

Newer, targeted drugs are an important part of treatment for most people with CLL. These medicines affect parts of the leukemia cells that make them different from normal cells.

Doctors are now trying to figure out the best combinations and sequences for giving these drugs and whether some might work better in people whose CLL cells have certain gene or chromosome changes.

Many new targeted drugs are also being tested for use in CLL clinical trials.

Immunotherapy

These types of medicines help a person's immune system find and attack the leukemia cells. Some types of immunotherapy are now being used to treat CLL, while many others are being studied.

CAR T-cell therapy

For CAR (chimeric antigen receptor) T-cell therapy, a person's own T cells are removed from their blood. (T cells are a type of white blood cell.)

In a lab, the T cells’ genes are altered to make them better at killing leukemia cells. These altered T cells are then grown (multiplied) and put back in the person's bloodstream so they can find and destroy CLL cells in the body.

These treatments may be an option for some people with CLL, typically after other treatments have been tried. To learn more, see Immunotherapy for Chronic Lymphocytic Leukemia.

CAR NK cell therapy

A related treatment now under study is CAR natural killer (NK) cell therapy.

For this treatment, white blood cells called natural killer (NK) cells are removed from donated umbilical cord blood and then altered in a lab, making them CAR NK cells. They are then put back in the person's blood to help find and destroy CLL cells in the body.

An advantage of this approach is that, unlike CAR T-cell therapy, it uses cells from donated cord blood, so it can be made ahead of time and frozen until needed.

Early results using CAR NK cell therapy against CLL have been promising, but more research is needed to see how useful it can be.

Bispecific monoclonal antibodies

These drugs are made up of parts of 2 different monoclonal antibodies (immune system proteins), so they can attach to proteins on 2 different types of cells at the same time, bringing them together.

In bispecific antibodies called T-cell engagers (TCEs), one part attaches to a protein on the leukemia cells, and the other part sticks to a protein on immune cells called T cells. This brings the immune cells together with the leukemia cells, helping the immune system mount a more effective response against them.

TCEs are becoming an important part of treatment for some types of cancer and are now being studied for use against CLL.

Vaccine therapy

The use of vaccines as cancer treatment is a research interest in many types of cancer. Instead of preventing cancer, these vaccines try to get the immune system to mount an attack against cancer cells in the body.

Some early studies are testing vaccines made from a person's own CLL cells and a protein that boosts the immune system's ability to kill the CLL cells. These studies are still in early phases, and it will take time before we know whether vaccine therapy works.