Section 04 · Monograph
Ocrelizumab
Reviewed Nov 2026FDA label
OcrevusAnti-CD20 mAb
- Forms
- IV: 300mg/10mL
- Dose
- 300mg IV, repeat in 2 weeks; then 600mg IV every 6 months
- MOA
- Depletes CD20+ B-cells
Indications
- Relapsing forms of multiple sclerosis: clinically isolated syndrome, relapsing-remitting disease, active secondary progressive disease, in adultsFDA-labeled
- Primary progressive multiple sclerosis, in adultsFDA-labeled
Mechanism of Action
- Recombinant humanized monoclonal antibody targeting CD20, a surface antigen expressed on pre-B and mature B lymphocytes
- Depletes circulating CD20+ B-cells, thought to reduce the autoimmune/inflammatory activity that drives MS relapses and progression
- Does not deplete stem cells or plasma cells, which lack CD20 expression, preserving some baseline humoral immunity
Full Dosing
Adult / usual
- First dose: 300mg IV infusion, followed by a second 300mg IV infusion 2 weeks later
- Subsequent doses: 600mg IV every 6 months, given as a single infusion or split into two 300mg infusions 2 weeks apart
- Premedicate with a corticosteroid and an antihistamine (consider an antipyretic) before every infusion to reduce infusion reaction risk
Pediatric
- Not established for pediatric use under age 10; pediatric RRMS data available for age 10+ weighing 25kg or more
Contraindications
- Active hepatitis B virus infection
- History of life-threatening infusion reaction to ocrelizumab
Drug Interactions
- Avoid live or live-attenuated vaccines during treatment and until B-cell repletion
- Caution with other immunosuppressive or immunomodulating therapies — additive immunosuppression risk
Adverse Effects
- Infusion reactions (common, can occur up to 24 hours post-infusion): pruritus, rash, throat irritation, flushing, hypotension
- Increased infection risk: upper respiratory infections, urinary tract infections
- Reduced immunoglobulin levels with long-term use
- Malignancy risk under continued long-term study
Monitoring Parameters
- Screen for hepatitis B before initiating
- Monitor immunoglobulin levels periodically with long-term therapy
- Monitor closely during and for at least 1 hour after the first infusion; at least 15 minutes after subsequent infusions
- Screen for active infection before each dose
Pregnancy & Lactation
- B-cell depletion observed in infant offspring in animal reproduction studies
- Effect on human infant B-cells and vaccine response after in-utero exposure is unknown — discuss timing of infant vaccinations if exposure occurred during pregnancy