Obinutuzumab
Pronunciation: pronunciation varies by local usage.
- Generic name
- obinutuzumab
- Brand names
- Gazyva
- Drug class
- CD20-directed cytolytic monoclonal antibody
- Form
- Injection for intravenous infusion
- Route
- Intravenous infusion
- Legal status
- Prescription-only biologic medicine
Availability and supply rules vary by country
Trade names by country: United States · Canada
Australia: · Full directory
What obinutuzumab is and how it works
Obinutuzumab is a biologic medicine that targets the CD20 protein on certain B cells, leading to cell death. It is given by intravenous infusion in a clinical or oncology setting for selected blood cancers and for active lupus nephritis. (1)
Obinutuzumab is a clinician-administered infusion medicine; it is not self-injected at home. The exact use, combination medicines, dosing schedule, and pre-treatment checks depend on the specific condition being treated. A specialist must confirm eligibility and the treatment plan.
Mechanism of action: how obinutuzumab works
Obinutuzumab is a humanised anti-CD20 monoclonal antibody of the IgG1 subclass. It binds to the CD20 antigen on the surface of B lymphocytes, mediating B-cell lysis through antibody-dependent cellular cytotoxicity, antibody-dependent cellular phagocytosis, and direct cell death. (1)
What obinutuzumab is used for
Previously untreated chronic lymphocytic leukemia
Obinutuzumab is used in combination with chlorambucil for eligible adults with previously untreated chronic lymphocytic leukemia. (1)
Relapsed or refractory follicular lymphoma
Obinutuzumab is used in combination with bendamustine followed by obinutuzumab monotherapy for adults with follicular lymphoma that has relapsed after, or is refractory to, a rituximab-containing regimen. (1)
Previously untreated follicular lymphoma
Obinutuzumab is used in combination with chemotherapy followed by obinutuzumab monotherapy for eligible adults with previously untreated stage II bulky, III, or IV follicular lymphoma. (1)
Active lupus nephritis
Obinutuzumab is used in combination with standard therapy for adults with active lupus nephritis. (1)
Before taking obinutuzumab
Do not take / not appropriate for
- Tell your treating clinical team if you have ever had a severe hypersensitivity reaction, including anaphylaxis or serum sickness, to obinutuzumab or any of its ingredients. Your clinical team must determine whether obinutuzumab can be administered. (all indications) (1)
- Obinutuzumab should not be given to patients with an active infection. Your clinical team will assess this before each treatment cycle. (all indications) (1)
Tell your clinician about
- Any history of hepatitis B infection, liver problems, or previous hepatitis B treatment.
- Any new or worsening neurologic symptoms such as confusion, memory loss, vision changes, difficulty walking, or weakness.
- Any current or recent infection, fever, or unexplained bruising or bleeding.
- Pregnancy, plans for pregnancy, or breastfeeding status — effective contraception is advised during treatment and for 6 months after the last dose.
- Any planned or recent vaccinations, especially live-virus vaccines.
- All other medicines, supplements, and previous cancer or biologic treatments.
How to take obinutuzumab
- Obinutuzumab is given by intravenous infusion in a clinic, hospital, or infusion centre by a trained healthcare professional. It is not a self-administered medicine.
- The exact dose, infusion schedule, cycle length, and combination medicines vary by the condition being treated. Your specialist will determine and manage your personal treatment plan.
- Premedication with a glucocorticoid, acetaminophen, and an antihistamine is required before each infusion to reduce the risk of infusion-related reactions.
- Do not alter the timing, dose, or treatment plan yourself — changes must be directed by your treating clinical team.
Procedures and treatment changes
Tell the treating team before surgery, procedures, or any medicine change. Do not alter treatment without the responsible clinician. (1)
Missed dose
Doses are managed entirely by your treating clinical team. If you believe a scheduled infusion has been missed or delayed, contact your specialist centre for instructions. Do not attempt to adjust the timing or dosing yourself.
Overdose
Obinutuzumab is administered under direct medical supervision. If you are concerned that an incorrect dose or infusion rate may have been given, speak to the treating clinician immediately. Any suspected medication error will be assessed and managed by the clinical team. (1)
Side effects
Side effects and their frequency vary depending on the condition being treated and the combination medicines used. Infusion-related reactions are very common, particularly with the first infusion.
Infusion-related reaction
What to notice: Symptoms during or shortly after infusion may include fever, chills, flushing, headache, nausea, changes in heart rate, shortness of breath, or changes in blood pressure.
What to do: Your clinical team monitors you during and after every infusion and will manage reactions according to their severity. Premedication is given to reduce this risk. (1)
Neutropenia (low white blood cell counts)
What to notice: Increased risk of infection; your blood counts will be monitored regularly. Neutropenia of Grade 3-4 severity occurred in approximately 33% of CLL patients, 35% of relapsed FL patients, and 49% of first-line FL patients.
What to do: Report any fever, sore throat, or signs of infection to your treatment team promptly. Antimicrobial prophylaxis is strongly recommended for prolonged neutropenia. (1)
Upper respiratory or other infections
What to notice: Symptoms such as cough, sore throat, nasal congestion, fever, or urinary symptoms. In previously untreated NHL, upper respiratory infections were reported in 50% of patients.
What to do: Report any signs of infection to your team before your next infusion. (1)
Fatigue
What to notice: Persistent tiredness or lack of energy.
What to do: Discuss persistent or troublesome fatigue with your treatment team. (1)
Thrombocytopenia or bleeding
What to notice: Unexplained bruising, bleeding gums, nosebleeds, or blood in stool or urine.
What to do: Contact your treatment team promptly for assessment. Platelet counts will be monitored. (1)
Tumour lysis syndrome
What to notice: Nausea, vomiting, muscle cramps, irregular heartbeat, or reduced urine output, typically occurring shortly after an infusion in patients with a high tumour burden.
What to do: Your team will assess your risk and may provide preventive hydration and medication. Report these symptoms urgently if they occur. (1)
Serious warnings
Hepatitis B virus reactivation — emergency
Symptoms: Worsening fatigue, yellowing of skin or eyes, dark urine, or abdominal pain may signal liver problems.
Action: Your clinical team must screen for hepatitis B before treatment and monitor you during and after treatment. Seek emergency care if you develop these symptoms. HBV reactivation can lead to liver failure and death. (1)
Progressive multifocal leukoencephalopathy (PML) — emergency
Symptoms: New or worsening confusion, memory loss, vision changes, difficulty walking, weakness on one side of the body, or speech problems.
Action: Contact your clinical team and seek emergency assessment immediately. PML is a rare but serious brain infection that can be fatal. (1)
Severe infusion-related reaction — emergency
Symptoms: Severe shortness of breath, chest pain, throat tightness, severe dizziness, or collapse during or shortly after an infusion.
Action: During or shortly after an infusion, your infusion team is trained to stop the infusion and provide emergency treatment immediately. If severe shortness of breath, chest pain, throat tightness, severe dizziness, or collapse occurs after you have left the infusion setting, seek emergency medical assessment right away. (1)
Interactions
| Medicine or test | Effect | Action |
|---|---|---|
| Live-virus vaccines | The safety and effectiveness of live-virus vaccines during obinutuzumab treatment are not established. | Tell your treatment team about any recent or planned vaccinations. Your specialist must determine when vaccination is appropriate; live-virus vaccines are avoided during treatment and until B-cell recovery is confirmed. (1) |
| Other drug-drug interactions | The prescribing information reports no significant drug-drug interactions have been discussed. | Give your specialist and pharmacist a complete list of all medicines and supplements before starting treatment. (1) |
Pregnancy, breastfeeding, kidney/liver function, age
Pregnancy
Obinutuzumab can cause B-cell depletion in infants exposed during pregnancy. Effective contraception is advised during treatment and for 6 months after the last dose. Discuss risks and benefits with your specialist. (1)
Breastfeeding
Patients are advised not to breastfeed during treatment and for 6 months after the last dose. Discuss your individual circumstances with your specialist. (1)
Children and adolescents
The safety and effectiveness of obinutuzumab in children and adolescents have not been established in the sources reviewed. Pending a dedicated paediatric-content verification step. (1)
Renal impairment
Renal impairment with creatinine clearance as low as 30 mL/min does not appear to affect obinutuzumab pharmacokinetics based on available data. Your specialist will assess your individual situation. (1)
Hepatic impairment
No specific dosing adjustment for hepatic impairment was identified in the sources reviewed. Pending a dedicated content-verification step.
Monitoring
Before starting
- Screen all patients for hepatitis B surface antigen (HBsAg) and hepatitis B core antibody (anti-HBc).
- Assess for any active infection; obinutuzumab should not be given during an active infection.
- Evaluate baseline blood counts including platelets, and assess tumour lysis syndrome risk in patients with high tumour burden.
- Confirm the exact diagnosis, indication, eligibility, and the planned combination therapy regimen.
- Review pregnancy status and contraception needs, and discuss risks of B-cell depletion in infants.
During treatment
- Monitor for infusion-related reactions during and after every infusion; premedication with glucocorticoid, acetaminophen, and antihistamine is required.
- Monitor complete blood counts regularly, including platelet counts; provide antimicrobial prophylaxis for patients with neutropenia lasting more than 1 week.
- Monitor for signs and symptoms of HBV reactivation during treatment and for several months after treatment ends.
- Remain vigilant for new or worsening neurologic symptoms that may suggest PML.
- Assess for tumour lysis syndrome in at-risk patients; provide adequate hydration and anti-hyperuricemic treatment as indicated.
- Avoid live-virus vaccines until B-cell recovery is confirmed.
Storage
Obinutuzumab is stored, prepared, and administered by the healthcare facility. Patients do not store or handle this medicine at home. The clinical team follows the product labelling for refrigerated storage, protection from light, and preparation for infusion.
Professional information
Clinician-facing context only. Use the current local prescribing information, indication-specific dosing schedule, and institutional protocols for premedication, infusion-rate management, and monitoring.
United States
Indication: Chronic lymphocytic leukemia
Dose summary: Cycle 1: 100 mg on Day 1 and 900 mg on Day 2 (split first dose), then 1,000 mg on Days 8 and 15. Cycles 2-6: 1,000 mg on Day 1 (28-day cycles), in combination with chlorambucil.
Renal context: Renal impairment (CrCl ≥30 mL/min) does not appear to affect pharmacokinetics. No dose adjustment recommended for mild-to-moderate impairment in the label. (1)
United States
Indication: Follicular lymphoma
Dose summary: Cycle 1: 1,000 mg on Days 1, 8, and 15 (in combination with bendamustine or chemotherapy depending on line of therapy). Subsequent cycles: 1,000 mg on Day 1. Maintenance (previously untreated FL): 1,000 mg every 2 months for up to 2 years as monotherapy.
Renal context: Renal impairment (CrCl ≥30 mL/min) does not appear to affect pharmacokinetics. No dose adjustment recommended for mild-to-moderate impairment in the label. (1)
United States
Indication: Lupus nephritis
Dose summary: 1,000 mg at initial infusion, Week 2, Week 24, Week 26, then every 6 months thereafter, in combination with standard therapy.
Renal context: Renal impairment (CrCl ≥30 mL/min) does not appear to affect pharmacokinetics. Patients with lupus nephritis have renal involvement by definition; the specialist must assess and monitor individually. (1)
Hepatic guidance
No hepatic-impairment-specific dosing adjustment was identified in the sources reviewed. Pending dedicated content-verification step.
Overdose note
Obinutuzumab is administered under direct clinical supervision. Any medication error is managed by the treating team with supportive monitoring and institutional protocols. (1)
Frequently asked questions
Can I inject obinutuzumab at home?
No. Obinutuzumab is given by intravenous infusion in a clinic, hospital, or infusion centre by a trained healthcare professional. It is not designed for home or self-administration. (1)
Why do I need premedication before each obinutuzumab infusion?
Premedication with a glucocorticoid, acetaminophen, and an antihistamine helps reduce the risk and severity of infusion-related reactions, which are common with obinutuzumab, especially with the first infusion. (1)
Can I receive live vaccines during obinutuzumab treatment?
Tell your treatment team about any planned vaccinations. Live-virus vaccines are avoided during obinutuzumab treatment and until your specialist confirms your B cells have recovered; your specialist determines the appropriate timing. (1)
What is the mechanism of action of obinutuzumab?
Obinutuzumab is a humanised anti-CD20 monoclonal antibody of the IgG1 subclass. It binds to the CD20 antigen on the surface of B lymphocytes, mediating B-cell lysis through antibody-dependent cellular cytotoxicity, antibody-dependent cellular phagocytosis, and direct cell death. (1)
What is the generic name of Obinutuzumab?
The generic name is obinutuzumab. It is sold under brand names including Gazyva. (1)
What class of drug is obinutuzumab?
Obinutuzumab is classed as: CD20-directed cytolytic monoclonal antibody. (1)
References
- GAZYVA (obinutuzumab) injection — prescribing informationU.S. Food and Drug Administration · United States · accessed 2026-08-05 · source 1
- GAZYVA (OBINUTUZUMAB) INJECTION, SOLUTION, CONCENTRATE [GENENTECH, INC.] — US prescribing information (DailyMed SPL)U.S. National Library of Medicine (DailyMed) · US · accessed 2026-08-14 · source 2
- Obinutuzumab Injection — patient drug information (MedlinePlus)U.S. National Library of Medicine (MedlinePlus) · US · accessed 2026-08-14 · source 3
- Gazyva — FDA approval record (Drugs@FDA BLA125486)U.S. Food and Drug Administration · US · accessed 2026-08-14 · source 4
- obinutuzumab — RxNorm normalized drug concept (RXCUI 974779)U.S. National Library of Medicine (RxNorm) · US · accessed 2026-08-14 · source 5
Brand names by country
Single-ingredient obinutuzumab names are shown separately by country. Product availability, strengths, and supply rules can change; combination products are not included here.
Priority countries
United States
- Gazyva1000 mg/40mL · genentech, inc.
Canada
- GAZYVA