Antibody therapy

Antibodies are proteins in our blood that fight infections. They are made naturally by our lymphocytes when we get an infection. They stick to proteins on the surface of bacteria and viruses and tell our body to get rid of them.

Monoclonal antibodies are molecules that are made in the laboratory. They are designed to recognize and attach to a specific part of a particular molecule. When a monoclonal antibody attaches to a cancer cell, it can stop or slow down its growth or it can signal to the immune system to recognize the cell and kill it.

The monoclonal antibodies obinutuzumab (Gazyva®), and rituximab (Rituxan®) recognize and attach to a molecule called CD20, which is found on the surface of most B cells, including CLL and SLL cells.

Antibody therapy is most often given in combination with chemotherapy drugs, which is called 'chemoimmunotherapy'. Like many chemotherapy drugs, antibody therapies are given by needle directly into a vein (IV infusion) or under the skin (subcutaneous).

Obinutuzumab (Gazyva®)

Obinutuzumb is an antibody that targets and attaches to the CD20 proteins found on CLL cells and some healthy blood cells. Once attached to the CD20 protein, obinutuzumab is thought to work in different ways, including:

  • By helping your own immune system destroy the cancer cells
  • By destroying the cancer cells directly

In addition, obinutuzumab can also harm healthy cells in your body.

Obinutuzumab has been approved by Health Canada for the treatment of patients with previously untreated CLL or SLL, when given together with the oral chemotherapy drug chlorambucil.

Rituximab (Rituxan®)

Rituximab is an antibody that targets and attaches to the CD20 proteins found on CLL cells and some healthy blood cells. Once attached to the CD20 protein, rituximab is thought to work in different ways, including:

  • By helping your own immune system destroy the cancer cells
  • By destroying the cancer cells directly

In addition, rituximab can also harm healthy cells in your body.

Rituximab has been approved by Health Canada for treatment, alone or in combination with other drugs, for treatment of those with previously untreated CLL and those who have received prior treatment.

Alemtuzumab

Alemtuzumab is an antibody that targets and attaches to the CD52 proteins found on CLL cells and some healthy blood cells. Once attached to the CD52 protein, alemtuzumab is thought to work by helping your own immune system destroy the cancer cells.

In addition, alemtuzumab can also harm healthy cells in your body.

Alemtuzumab is approved by Health Canada for the treatment of CLL in patients who have been treated with alkylating agents and who have failed fludarabine therapy.