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Generic name: obinutuzumab
Brand name: Gazyva
Dosage form: intravenous (infusion) injection
Drug class: CD20 monoclonal antibodies

Medically reviewed by Philip Thornton, DipPharm. Last updated on Apr 4, 2023.

What is obinutuzumab?

Obinutuzumab is a type of targeted chemotherapy drug for the treatment of certain blood cancers.

Obinutuzumab is a biological drug called a monoclonal antibody that targets and attaches to CD20, a protein found on the surface of a type of white blood cells called B-cells.

B-cells, or B-lymphocytes as they are also known, usually help your body fight off infection, but some people produce abnormal numbers of B-cells which leads to cancer.

Obinutuzumab works by binding to normal and cancerous B-cells, marking them for destruction. Obinutuzumab works by calling in your own immune system cells to attack and break apart the marked B-cells, and by activating processes within the B-cells that instruct them to die.

Obintuzumab was approved by the US Food and Drug Administration (FDA) in 2013. No biosimilars of obintuzumab have been approved. Biosimilars are highly similar versions of the drug that are designed to have the same effect on a person, but a biosimilar is not identical to the original version of the drug.

What is obinutuzumab used for?

Obinutuzumab is a prescription medication used in combination with:

Important information

Obintuzumab can cause serious side effects including:

Who should not receive obinutuzumab?

Do not receive obinutuzumab if you have had an allergic reaction (e.g., anaphylaxis or serum sickness) to obinutuzumab. Tell your healthcare provider if you have had an allergic reaction to obinutuzumab or any other ingredients in it in the past. See below for a complete list of ingredients in obintuzumab.

What should I tell my doctor before receiving obinutuzumab?

Before receiving obinutuzumab, tell your healthcare provider about all of your medication conditions, including if you:

How should I receive obinutuzumab?

What happens if I miss a dose?

If you miss a dose of obinutuzumab it should be administered as soon as possible. Your healthcare professional will discuss with you what adjustments need to be made to your treatment schedule if you miss a dose.

What should I avoid while receiving obinutuzumab?

While receiving treatment with obinutuzumab you should avoid vaccination with live viral vaccines.

Dosing information

What are the side effects of obinutuzumab?

Obinutuzumab can cause serious side effects including:

The most common side effects seen with obinutuzumab in a study that included previously untreated follicular lymphoma patients were:

These are not all of the possible side effects of obinutuzumab. Tell your healthcare provider about all of your side effects. Call your doctor or pharmacist for medical advice about side effects. You may report side effects to Genentech at 1-888-835-2555 or FDA at 1-800-FDA-1088 or


Tell your healthcare provider about all the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements.

Especially tell your doctor if you take medication:

Pregnancy and breastfeeding

Tell your doctor if you are pregnant, think that you might be pregnant, or plan to become pregnant. Obinutuzumab may harm your unborn baby. Speak to your doctor about using obinutuzumab while you are pregnant. Talk to your doctor or your child’s doctor about the safety and timing of live virus vaccinations to your infant if you received obinutuzumab during pregnancy. Women of childbearing potential should use effective contraception while taking obinutuzumab and for 6 months after your treatment.

Tell your doctor if you are breastfeeding or plan to breastfeed. Because of the potential risk of serious side reactions in breastfed children, women should not breastfeed while taking obinutuzumab and for 6 months after your last dose.


Keep out of reach of children.

What are the ingredients in obinutuzumab?

Active ingredient:obinutuzumab

Inactive ingredients:histidine, histidine monohydrochloride monohydrate, trehalose dihydrate, poloxamer 188, water

Obinutuzumab is manufactured by Genentech, Inc. A Member of the Roche Group, South San Francisco, CA 94080-4990.

Frequently asked questions

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.