Targeted therapy for chronic lymphocytic leukemia

Targeted therapy is sometimes used to treat chronic lymphocytic leukemia (CLL). It uses drugs to target specific molecules (such as proteins) on the surface of cancer cells. These molecules help send signals that tell cells to grow or divide. By targeting these molecules, the drugs stop the growth and spread of cancer cells while limiting harm to normal cells. Targeted therapy may also be called molecular targeted therapy.

You may have targeted therapy:

• to treat intermediate-risk or high-risk CLL
• when CLL no longer responds to standard chemotherapy treatments

Your healthcare team will consider your personal needs to plan the drugs, doses and schedules of targeted therapy. You may also receive other treatments.

Targeted therapy may be given in combination with chemotherapy drugs. The most common targeted therapy drugs used are:

• rituximab (Rituxan)
• alemtuzumab (Campath)
• ofatumumab (Arzerra)
• obinutuzumab (Gazyva)
• ibrutinib (Imbruvica)
• idelalisib (Zydelig)
• venetoclax (Venclexta)

Rituximab, ofatumumab and obinutuzumab are given by a needle in a vein (intravenously). Alemtuzumab is given either intravenously or by an injection just under the skin (called subcutaneous, or SC, injection). Ibrutinib is given as a capsule by mouth. Idelalisib and venetoclax are given as a tablet by mouth.

Side effects can happen with any type of treatment for CLL but everyone’s experience is different. Some people have many side effects. Other people have few or none at all.

Targeted therapy doesn’t usually damage healthy cells, so it tends to cause fewer and less severe side effects than chemotherapy and radiation therapy. Chemotherapy and radiation therapy can damage healthy cells along with cancer cells.

If side effects develop with targeted therapy, they can happen any time during, immediately after or a few days or weeks after targeted therapy. Sometimes late side effects develop months or years after targeted therapy. Most side effects go away on their own or can be treated, but some side effects may last a long time or become permanent.

Side effects of targeted therapy will depend mainly on the type of drug, the dose, and your overall health. Some common side effects of targeted therapy for CLL are:

• flu-like symptoms, such as fever and chills
• fatigue
• diarrhea
• nausea and vomiting
• skin problems, including redness, itching and dryness
• dizziness
• low blood cell counts (called bone marrow suppression)
• allergic reactions
• tumour lysis syndrome (venetoclax)

Tell your healthcare team if you have these side effects or others you think might be from targeted therapy. The sooner you tell them of any problems, the sooner they can suggest ways to help you deal with them.

Details on specific drugs change quite regularly. Find out more about sources of drug information and where to get details on specific drugs.

Find out more about targeted therapy. To make the decisions that are right for you, ask your healthcare team questions about targeted therapy.