Ocrelizumab
Ocrelizumab is a CD20-directed cytolytic monoclonal antibody used to treat multiple sclerosis. Ocrelizumab is used for Relapsing forms of multiple sclerosis in adults, Primary progressive multiple sclerosis in adults and Relapsing-remitting multiple sclerosis in pediatric patients.
Pronunciation: pronunciation varies by local usage.
- Generic name
- ocrelizumab
- Brand names
- OCREVUS, Ocrevus, Ocrevus SC
- Drug class
- CD20-directed cytolytic monoclonal antibody
- Form
- Concentrate solution for intravenous infusion; must be diluted before administration
- Route
- Intravenous infusion
- Legal status
- Prescription-only medicine
Availability and supply rules vary by country
Trade names by country: United States · Australia · New Zealand
Australia: Ocrevus, Ocrevus SC · Full directory
What ocrelizumab is and how it works
Ocrelizumab is a CD20-directed cytolytic monoclonal antibody used to treat multiple sclerosis. It is given by intravenous infusion by a doctor or nurse. The US FDA label includes relapsing forms of multiple sclerosis in adults, primary progressive multiple sclerosis in adults, and relapsing-remitting multiple sclerosis in pediatric patients 10 years of age and older who weigh 25 kg or more. (1) (2)
Ocrelizumab may help control multiple sclerosis symptoms but does not cure them. Infusion reactions can occur during an infusion and for up to 24 hours afterward. Treatment also carries warnings about serious infections, progressive multifocal leukoencephalopathy, immune-mediated colitis, liver injury, and possible increased malignancy risk. A clinician must assess infection status, hepatitis B status, vaccination status, and other individual risks before and during treatment.
Mechanism of action: how ocrelizumab works
Ocrelizumab is a CD20-directed cytolytic monoclonal antibody. MedlinePlus describes it as a monoclonal antibody that works by stopping certain cells of the immune system from causing damage. (2) (1) (3)
What is Ocrelizumab used for?
Relapsing forms of multiple sclerosis in adults
US label: Ocrelizumab is indicated for relapsing forms of multiple sclerosis, including clinically isolated syndrome, relapsing-remitting disease, and active secondary progressive disease, in adults. (2) (1)
Primary progressive multiple sclerosis in adults
US label: Ocrelizumab is indicated for primary progressive multiple sclerosis in adults. (2)
Relapsing-remitting multiple sclerosis in pediatric patients
US label: Ocrelizumab is indicated for relapsing-remitting multiple sclerosis in pediatric patients 10 years of age and older who weigh 25 kg or more. (2)
Relapsing and primary progressive multiple sclerosis in Australia
AU healthdirect page: OCREVUS is indicated for treatment of patients with relapsing forms of multiple sclerosis to delay progression of physical disability and to reduce frequency of relapse, and for treatment of patients with primary progressive multiple sclerosis to delay progression of physical disability. (3)
Before taking ocrelizumab
Do not take / not appropriate for
- Do not receive ocrelizumab if you have active hepatitis B virus infection. Hepatitis B screening is required before starting treatment, and the treating clinician uses the blood test results to determine eligibility. (all products) (2) (1)
- Do not receive ocrelizumab if you have a history of a life-threatening infusion reaction to ocrelizumab. (all products) (2)
Tell your clinician about
- Any allergy to ocrelizumab, other medicines, or any ingredient in the injection.
- All prescription and nonprescription medicines, vitamins, minerals, nutritional supplements, and herbal products you are taking or plan to take.
- Any history of hepatitis B infection, or any current or recent infection.
- Any history of inflammatory bowel disease, including Crohn's disease or ulcerative colitis.
- Pregnancy, plans for pregnancy, or breastfeeding. Females of reproductive potential should use effective contraception during treatment and for 6 months after the final dose.
- Any recent vaccination or scheduled vaccination, because certain vaccines may need to be given before treatment starts.
- Any history of a serious infusion reaction, cancer, liver problems, or recurrent infections.
Ocrelizumab dosage and how to take it
- Ocrelizumab is given by a doctor or nurse as an intravenous infusion, not by self-injection.
- US label: start doses are given at week 0 and week 2, then maintenance doses are given every 6 months. The exact dose, infusion number, and duration depend on age, body weight, indication, and the current US label.
- Premedication such as a corticosteroid and an antihistamine is given before each infusion to reduce infusion reactions. An antipyretic may also be considered.
- A clinician will monitor closely during the infusion and for at least 1 hour after it is finished. Infusion reactions can occur up to 24 hours after the infusion.
- Do not change the dose, interval, infusion setting, or monitoring plan yourself. Report any new or worsening symptoms promptly.
Procedures and treatment changes
Tell the treating team before surgery, procedures, or any medicine change. Do not alter treatment without the responsible clinician. (1) (2) (3)
Missed dose
If you miss an infusion appointment, call your doctor or clinic as soon as possible to reschedule. Do not try to make up or alter the infusion schedule yourself.
Overdose
If an overdose is suspected, call the poison control helpline at 1-800-222-1222 or visit poisonhelp.org. If the person has collapsed, had a seizure, has trouble breathing, or cannot be awakened, call emergency services immediately. (1)
Ocrelizumab side effects
Infusion reactions are common, especially with the first infusion. Serious infections, progressive multifocal leukoencephalopathy, immune-mediated colitis, liver injury, and possible increased malignancy risk have also been reported. Report new or worsening symptoms promptly.
Infusion-related reaction
What to notice: Itching, rash, hives, redness at the injection site, cough, wheezing, difficulty breathing or swallowing, throat irritation, mouth or throat pain, shortness of breath, swelling of the face, eyes, mouth, throat, tongue, or lips, flushing, fever, tiredness, headache, dizziness, nausea, or a racing heartbeat.
What to do: Tell the doctor or nurse immediately during the infusion or within 24 hours after the infusion. If symptoms occur after leaving the medical facility, call your doctor immediately or get emergency medical attention. (1) (2)
Swelling or pain in hands, arms, legs, or feet
What to notice: Swelling or pain in the hands, arms, legs, or feet.
What to do: Tell your doctor if this is severe or does not go away. (1)
Signs of infection
What to notice: Fever, chills, persistent cough, or other signs of infection; mouth sores; shingles; sores around the genitals or rectum; skin infection; or herpes symptoms such as cold sores, genital sores, eye redness, eye pain, fever, skin rash, pain, itching, decreased visual acuity, headache, neck stiffness, or change in mental status.
What to do: Contact your healthcare provider promptly for assessment. (1) (2)
Progressive multifocal leukoencephalopathy symptoms
What to notice: Progressive weakness on one side of the body, clumsiness of arms and legs, vision changes, changes in thinking, memory, and orientation, confusion, or personality changes.
What to do: Contact your healthcare provider immediately for assessment. (1) (2)
Immune-mediated colitis or bowel symptoms
What to notice: Diarrhea or more frequent, loose stools; stools that are black, tarry, sticky, or contain blood; abdominal pain or tenderness.
What to do: Contact your healthcare provider promptly for evaluation. (1) (2)
Vision, headache, or meningeal symptoms
What to notice: Changes in vision, severe or persistent headache, confusion, eye redness or eye pain, or stiff neck.
What to do: Call your doctor promptly or get immediate medical evaluation. (1)
Possible liver injury
What to notice: New or unexplained symptoms that may indicate liver injury. The supplied research notes do not list the exact patient-reported symptoms in the excerpt; liver function tests are part of monitoring.
What to do: Report symptoms promptly so the clinician can assess liver function. (2)
Serious warnings
Infusion reactions, including anaphylaxis — emergency
Symptoms: Rash, itching, hives, redness, difficulty breathing or swallowing, cough, wheezing, throat irritation, mouth or throat pain, shortness of breath, swelling of the face, eyes, mouth, throat, tongue, or lips, flushing, fever, fatigue, headache, dizziness, nausea, or a racing heartbeat.
Action: During an infusion, staff will monitor and treat. If symptoms occur after leaving the medical facility, call your doctor immediately or get emergency medical attention. The treating clinician will decide whether to pause, adjust, or discontinue treatment based on severity. (1) (2)
Serious infections — serious
Symptoms: Fever, chills, persistent cough, painful urination, cold sores, shingles, genital sores, skin infection, or other signs of infection.
Action: Contact your healthcare provider promptly for signs of infection. An active infection may require delaying an infusion until the infection resolves. (2) (1)
Progressive multifocal leukoencephalopathy — emergency
Symptoms: Progressive weakness on one side of the body or clumsiness of limbs, disturbance of vision, and changes in thinking, memory, and orientation leading to confusion and personality changes.
Action: Contact your healthcare provider immediately if these symptoms develop. The treating clinician will decide whether to withhold ocrelizumab. (2) (1)
Hepatitis B virus reactivation or liver injury — serious
Symptoms: Hepatitis B screening is required before treatment; patients at risk may need monitoring. Clinically significant liver injury has occurred with anti-CD20 B-cell depleting therapies including ocrelizumab.
Action: Report any symptoms that may indicate liver problems promptly. The clinician will order liver tests before starting and during treatment as clinically indicated. (2)
Malignancy risk — important
Symptoms: An increased risk of malignancy, including breast cancer, may exist. No specific symptom is listed in the supplied notes as a reliable screening method.
Action: Discuss the risk with your clinician and follow standard breast cancer screening guidelines. (2) (1)
Interactions
| Medicine or test | Effect | Action |
|---|---|---|
| Live or live-attenuated vaccines | Live or live-attenuated vaccines are not recommended during ocrelizumab treatment and after discontinuation until B-cell repletion. Non-live vaccines may also need timing adjustment. | Complete age-appropriate live or live-attenuated vaccines at least 4 weeks before starting ocrelizumab when possible, and non-live vaccines at least 2 weeks before starting when possible. Do not receive vaccinations during treatment without talking to your doctor. (2) (1) |
| Other prescription and nonprescription medicines, vitamins, minerals, supplements, and herbal products | Your doctor may need to change the doses of your other medicines or monitor you carefully for side effects. | Give your doctor and pharmacist a complete list of everything you take or plan to take. (1) |
| Active infection | Ocrelizumab administration should be delayed if there is an active infection until the infection resolves. | Tell the treating clinician about any current infection before every infusion. (2) (1) |
Pregnancy, breastfeeding, kidney/liver function, age
Pregnancy and reproductive potential
Based on animal data, ocrelizumab may cause fetal harm. Females of reproductive potential should use effective contraception during treatment and for 6 months after the last infusion. If you become pregnant while receiving ocrelizumab, call your doctor. If ocrelizumab was received during pregnancy, tell the baby's doctor after birth because the baby may need to delay certain vaccines. (2) (1)
Breastfeeding
There are no data on the presence of ocrelizumab in human milk, the effects on the breastfed infant, or the effects on milk production. The benefits of breastfeeding should be considered along with the mother's clinical need for ocrelizumab and any potential adverse effects on the infant. (2)
Children and adolescents
US label: ocrelizumab is indicated for relapsing-remitting multiple sclerosis in pediatric patients 10 years of age and older who weigh 25 kg or more. Dosing differs by weight band: 25 kg to less than 35 kg, or 35 kg and above. Do not extrapolate adult dosing to a child. (2)
People with hepatitis B, active infection, or inflammatory bowel disease
Active hepatitis B virus infection is a contraindication. Screening is needed before treatment. People with any current infection, history of hepatitis B, or inflammatory bowel disease such as Crohn's disease or ulcerative colitis should tell their clinician. (2) (1)
Monitoring
Before starting
- Screen for hepatitis B virus before starting ocrelizumab.
- Obtain quantitative serum immunoglobulins, aminotransferases, alkaline phosphatase, and bilirubin before starting.
- Review vaccination status and complete age-appropriate live or live-attenuated vaccines at least 4 weeks before starting, and non-live vaccines at least 2 weeks before starting when possible.
- Assess for active infection before every infusion; delay the infusion if active infection is present until it resolves.
- Confirm pregnancy status and contraceptive plan for females of reproductive potential.
During treatment
- Observe for infusion reactions during the infusion and for at least 1 hour after completion. Infusion reactions can occur up to 24 hours after infusion.
- Monitor for signs of infection, herpes, progressive multifocal leukoencephalopathy, immune-mediated colitis, and liver injury.
- Monitor serum immunoglobulins during and after discontinuation until B-cell repletion, especially if recurrent serious infections are suspected.
- Keep all appointments and laboratory tests ordered by the doctor.
Storage
AU product information: store at 2 to 8 degrees Celsius, protect from light, do not freeze, refrigerate. Shelf lifetime is 24 months. Healthcare settings should follow product-specific preparation and storage instructions and should not use a product with an uncertain storage history.
Professional information
Clinician-facing context only. Use the current local indication, dosing, infusion-reaction protocol, infection screening, and product information. The supplied research notes include US and AU sources only; no NHS UK page was available.
United States (US FDA label)
Indication: Relapsing forms of multiple sclerosis in adults; primary progressive multiple sclerosis in adults; relapsing-remitting multiple sclerosis in pediatric patients 10 years of age and older who weigh 25 kg or more.
Dose summary: US label: Adults and pediatric patients (10 years of age and older) who weigh 35 kg or more: start dose 300 mg intravenous infusion, followed two weeks later by a second 300 mg intravenous infusion; subsequent doses 600 mg intravenous infusion every 6 months. Pediatric patients (10 years of age and older) who weigh 25 kg to less than 35 kg: start dose 150 mg intravenous infusion, followed two weeks later by a second 150 mg intravenous infusion; subsequent doses 300 mg intravenous infusion every 6 months. Must be diluted before administration.
Renal context: The supplied research notes do not state a renal impairment dose adjustment. Do not infer a web-based renal adjustment. (2)
Australia (healthdirect ARTG/CMI page)
Indication: Relapsing forms of multiple sclerosis to delay progression of physical disability and reduce frequency of relapse; primary progressive multiple sclerosis to delay progression of physical disability.
Dose summary: The supplied AU page does not provide a dose or administration schedule in these notes. Use the current Australian product information and PBS criteria; do not merge US and AU dosing.
Renal context: Not stated in the supplied AU source. (3)
Hepatic guidance
Before starting, obtain serum aminotransferases, alkaline phosphatase, and bilirubin levels. Clinically significant liver injury has occurred. The US label directs discontinuation in patients with evidence of liver injury in the absence of an alternative cause; this is a clinician decision.
Overdose note
In case of suspected overdose, contact poison control at 1-800-222-1222 or emergency services if the person has collapsed, had a seizure, has trouble breathing, or cannot be awakened. The supplied notes do not give a specific antidote or dose-removal protocol. (2) (1) (3)
Frequently asked questions
Does ocrelizumab cure multiple sclerosis?
No. Ocrelizumab may help control multiple sclerosis symptoms, but it does not cure the disease. (1)
How often is ocrelizumab given?
US label: start doses are given at week 0 and week 2, then maintenance doses are given every 6 months. The exact dose depends on age, body weight, and indication. (2) (1)
Can I receive vaccines while being treated with ocrelizumab?
Live or live-attenuated vaccines are not recommended during treatment and after discontinuation until B-cell repletion. Talk with your doctor before receiving any vaccination. (2) (1)
What should I do if I miss an ocrelizumab infusion appointment?
Call your doctor or clinic as soon as possible to reschedule the appointment. Do not try to make up or alter the infusion schedule yourself. (1)
What is the mechanism of action of ocrelizumab?
Ocrelizumab is a CD20-directed cytolytic monoclonal antibody. MedlinePlus describes it as a monoclonal antibody that works by stopping certain cells of the immune system from causing damage. (2) (1) (3)
References
- Ocrelizumab Injection: MedlinePlus Drug InformationMedlinePlus, U.S. National Library of Medicine · United States · accessed 2026-10-13 · source 1
- OCREVUS (ocrelizumab) injection, solution, concentrate — prescribing informationU.S. National Library of Medicine, DailyMed · United States · dated 2024 · accessed 2026-10-13 · source 2
- OCREVUS ocrelizumab 300 mg/10 mL concentrate solution for infusion vial — medicine informationhealthdirect Australia · Australia · accessed 2026-10-13 · source 3
Brand names by country
Single-ingredient ocrelizumab names are shown separately by country. Product availability, strengths, and supply rules can change; combination products are not included here.
Priority countries
United States
- OCREVUSinjection · 300 mg0mL · genentech, inc.regulator source
Australia
- Ocrevusreference source
- Ocrevus SCreference source
New Zealand
- Ocrevusreference source
- Ocrevus SCreference source