Ocrelizumab (Ocrevus) Dosing
Ocrelizumab is administered as an initial dose of 300 mg IV infusion, followed 2 weeks later by a second 300 mg IV infusion, then 600 mg IV infusion every 6 months thereafter. 1
Initial Dosing Regimen
First dose: 300 mg IV infusion
- Start at 30 mL/hour
- Increase by 30 mL/hour every 30 minutes
- Maximum rate: 180 mL/hour
- Duration: approximately 2.5 hours or longer
Second dose (2 weeks later): 300 mg IV infusion
- Same infusion parameters as first dose
Maintenance Dosing (Every 6 Months)
Standard maintenance: 600 mg IV infusion every 6 months (starting 6 months after the first initial infusion)
You have two options for the 600 mg maintenance infusion 1:
Option 1: Standard 3.5-hour infusion
- Start at 40 mL/hour
- Increase by 40 mL/hour every 30 minutes
- Maximum rate: 200 mL/hour
- Duration: approximately 3.5 hours or longer
Option 2: Shortened 2-hour infusion (if no prior serious infusion reactions)
- Start at 100 mL/hour for first 15 minutes
- Increase to 200 mL/hour for next 15 minutes
- Increase to 250 mL/hour for next 30 minutes
- Increase to 300 mL/hour for remaining 60 minutes
- Duration: approximately 2 hours or longer
The 2-hour infusion is only appropriate if the patient has had no serious infusion reactions with any previous ocrelizumab infusion. 1 Recent evidence confirms that this shortened infusion maintains similar safety profiles with infusion-related reaction rates of 26.5% (conventional) versus 28.8% (shortened), with no serious IRRs observed 2.
Premedication Requirements
Mandatory premedication approximately 30 minutes before each infusion 1:
- Methylprednisolone 100 mg IV (or equivalent corticosteroid)
- Antihistamine (e.g., diphenhydramine) given 30-60 minutes prior
- Antipyretic (e.g., acetaminophen) may also be considered
Missed or Delayed Doses
If a planned infusion is missed, administer ocrelizumab as soon as possible—do not wait until the next scheduled dose. Reset the schedule to give the next dose 6 months after the missed dose is administered. Doses must be separated by at least 5 months. 1
Extended Interval Dosing
Recent real-world evidence demonstrates that extended interval dosing (EID) beyond 6 months does not result in significantly worse clinical or radiological outcomes 3. One study found that restarting with a full 600 mg dose after treatment interruptions of 7-9 months (moderate interval) or >9 months (long interval) showed no increased risk of infusion-related reactions compared to standard 6-month intervals 4. However, B-cell repopulation occurs more frequently with extended intervals 3.
Reduced Dosing Considerations
Real-world data from 300 mg dosing every 6 months (half the standard dose) showed no significant differences in clinical or radiological outcomes compared to standard 600 mg dosing 3. However, this is not FDA-approved and should only be considered in specific circumstances.
Post-Infusion Monitoring
Observe patients for at least 1 hour after completion of each infusion to monitor for infusion-related reactions 1.
Special Populations
Pediatric dosing (ages 10-17):
- Body weight <35 kg: 300 mg every 24 weeks
- Body weight ≥35 kg: 600 mg every 24 weeks 5
Renal/hepatic impairment: No dose adjustment required for mild impairment; no data available for severe impairment 1.