You may already be infected with hepatitis B (a virus that infects the liver and may cause severe liver damage) but not have any symptoms of the disease. In this case, obinutuzumab injection may increase the risk that your infection will become more serious or life-threatening and you will develop symptoms. Tell your doctor if you have or ever had hepatitis B virus infection. Your doctor will order a blood test to see if you have an inactive hepatitis B virus infection. If necessary, your doctor may give you medication to treat this infection. Your doctor will also monitor you for signs of hepatitis B infection during and for several months after your treatment with obinutuzumab. If you experience any of the following symptoms during or after your treatment, call your doctor immediately: excessive tiredness, yellowing of the skin or eyes, loss of appetite, nausea or vomiting, stomach pain, or dark urine.

Some people who received obinutuzumab developed progressive multifocal leukoencephalopathy (PML; a rare infection of the brain that cannot be treated, prevented, or cured and that usually causes death or severe disability) during their treatment. If you experience any of the following symptoms, call your doctor immediately: new or sudden changes in thinking or confusion, dizziness, loss of balance, difficulty talking or walking, new or sudden changes in vision, or any other unusual symptoms that develop suddenly.

Keep all appointments with your doctor and the laboratory. Your doctor will order certain tests to check your body’s response to obinutuzumab injection.

Talk to your doctor about the risks of receiving obinutuzumab injection.

Obinutuzumab injection is used alone or in combination with other medication(s) to treat chronic lymphocytic leukemia (CLL; a type of cancer of the white blood cells) and to treat follicular non-Hodgkin’s lymphoma (NHL; a slow-growing blood cancer). Obinutuzumab injection is in a class of medications called monoclonal antibodies. It works by killing cancer cells.

Your doctor will review your specific type of cancer and past treatment history and other available treatments to determine if obinutuzumab is right for you.

Obinutuzumab injection comes as a solution (liquid) to be added to fluid and slowly injected intravenously (into a vein) by a doctor or nurse in a medical office or hospital. Your doctor will select a schedule to give you obinutuzumab injection along with other medications that is best to treat your condition.

Your doctor may need to interrupt or stop your treatment if you experience certain side effects. Your doctor will give you other medications to prevent or treat certain side effects before you receive each dose of obinutuzumab injection. Tell your doctor or nurse if you experience any of the following during or within 24 hours after you receive obinutuzumab: dizziness, lightheadedness, fainting, fast heartbeat, chest pain, difficulty breathing, swelling of the throat, nausea, vomiting, fatigue, diarrhea, sudden reddening of the face, neck, or upper chest, rash, headache, chills, and fever.

Be sure to tell your doctor how you are feeling during your treatment with obinutuzumab injection.

This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.

Before receiving obinutuzumab injection,

• tell your doctor and pharmacist if you are allergic to obinutuzumab, any other medications, or any of the ingredients in obinutuzumab injection. Ask your pharmacist for a list of the ingredients.
• tell your doctor and pharmacist what other prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take. Be sure to mention any medications for high blood pressure. Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
• tell your doctor if you have or have ever had heart, lung, kidney, or liver disease. Also tell your doctor if you have any type of infection now or if you have or have ever had an infection that would not go away or an infection that comes and goes.
• tell your doctor if you are pregnant or plan to become pregnant. You should use effective birth control to prevent pregnancy during your treatment with obinutuzumab injection and for 6 months after your final dose. Talk to your doctor about birth control methods that will work for you. If you become pregnant while receiving obinutuzumab injection, call your doctor.
• tell your doctor if you are breastfeeding. You should not breastfeed while you are receiving obinutuzumab and for 6 months after your final treatment dose.
• if you are having surgery, including dental surgery, tell the doctor or dentist that you are receiving obinutuzumab injection.
• do not have any vaccinations without talking to your doctor.

Unless your doctor tells you otherwise, continue your normal diet.

If you miss an appointment to receive obinutuzumab, call your doctor right away.

Obinutuzumab injection may cause side effects. Tell your doctor if this symptom is severe or does not go away:

• muscle or joint pain
• constipation
• headache
• difficulty falling asleep or staying asleep
• decreased appetite
• itching

Some side effects can be serious. If you experience any of these symptoms or those listed in the IMPORTANT WARNING or HOW section, call your doctor immediately or get emergency medical treatment:

• fever, chills, cough, sore throat, or other signs of infection
• unusual bleeding or bruising
• unusual tiredness or weakness
• pain, tenderness, or redness in one leg
• shortness of breath, new or worsening cough, coughing up blood
• stomach area pain, nausea, vomiting, fever, or chills
• chest pain, joint pain, and fever
• decreased urination frequency or amount

Obinutuzumab injection may cause other side effects. Call your doctor if you have any unusual problems while receiving this medication.

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration’s (FDA) MedWatch Adverse Event Reporting program online (http://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at https://www.poisonhelp.org/help. If the victim has collapsed, had a seizure, has trouble breathing, or can’t be awakened, immediately call emergency services at 911.

Ask your pharmacist any questions you have about obinutuzumab injection.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.

• Gazyva^®