How this Targeted Therapy Treats Certain B Cell Blood Cancers

Zydelig (Idelalisib) is an FDA approved cancer treatment for certain types of blood cancers that have relapsed.

Unlike standard chemotherapy, Zydelig is considered a targeted therapy, as it identifies and then attacks cancerous cells, while striving to cause less damage to the patient’s healthy cells.

Targeted therapies such as Zydelig target the genes or proteins that help cancer cells proliferate.

By identifying these cancer causing cells, a cancer drug treatment like Zydelig strives to halt the ability of the cancer to grow and to spread.

Types of Blood Cancers Zydelig Treats

Zydelig is approved for the treatment of the following types of blood cancers:

  • Chronic lymphocytic leukemia (CLL) that has relapsed after initial cancer treatment in combination with the drug Rituxan.

  • Small lymphocytic lymphoma (SLL) after 2 or more prior cancer treatments.

  • Follicular Lymphoma, a form of non-Hodgkin lymphoma, after two or more prior cancer treatments.

How Zydelig Works
Zydelig works by blocking certain proteins that are located within the cancer cells. These proteins help promote the growth of the cancer.

Zydelig is considered a P13K inhibitor drug because it helps to inhibit, or block, the growth of a protein called PI3K delta, which is important in the activation and proliferation of B cells, which are a type of white blood cell. Many healthy B cells eventually develop into plasma cells, which are cells that produce the antibodies, or proteins, that are necessary for the body to fight off infections.

There are usually a higher than normal levels of the P12K protein in many types of B-cell cancers, such as chronic lymphocytic leukemia (CLL).

Because this protein promotes the growth and longevity of leukemia and lymphoma cancer cells, targeted cancer therapies like Zydelig may shrink the cancer, or stop the cancer from growing.

Zydelig helps with blood counts and also shrinks swollen lymph glands. This treatgment is helping people with certain B cell cancers to improve and control their cancers better than if they did not take Zydelig.

Developed by Gilead, Zydelig is given as a pill, which is taken orally twice a day with or without food. Tablets should be swallowed whole, with a glass of water, and should not be crushed or chewed.

Treatment is continued for as long as it is working or until intolerable side effects develop.

Possible Side Effects


As is the true with most cancer treatments, patients taking Zydelig may experience some possible side effects.

Common Side Effects

  • Diarrhea

  • Fever – sometimes referred to as pyrexia.

  • Fatigue – A feeling exhaustion that is usually not relieved by rest.

  • Nausea

  • Cough

  • Abdominal Pain

  • Chills

  • Rash

More Serious Side Effects
Aside from more common side effects previously mentioned, Zydelig may cause more serious and potentially life threatening side effects:

  • Live Damage

  • Severe Diarrhea or colitis.

  • Inflammation of the Lungs

  • Gastrointestinal Tears- intestinal perforation.

  • Severe Skin Reactions – developing sores or ulcers on the skin, lips, mouth or rash, blisters or peeling skin.

  • Allergic Reaction – developing shortness of breath, difficulty swallowing.

  • Neutropenia – abnormally low white blood cell counts.

  • Infection

Some side effects may be different if the patient also receives other types of cancer drugs. It is important to inform your health care providers as soon as possible if you have any concerns, or if there are any side effects, or if these are severe. Your health care team can help you manage most side effects.

It is also important to alert your oncology team about any other types of medicines you may be taking, including herbal supplements, vitamins and over the counter drugs. Some of these medicines and supplements may create a reaction with the treatment, or interfere with the how the drug works.

Because Zydelig may cause fetal harm, it is important to not be pregnant or become pregnant while taking this treatment. Breastfeeding is also not recommended, as this treatment can also get into breast milk.

Zydelig continues to offer hope as a new second-line option for the treatment of certain blood cancers, where standard first line treatments are no longer working.