mosunetuzumab at a glance
Medicine class
Anti-CD20/CD3 bispecific monoclonal antibody
Licensed use
Previously treated relapsed or refractory follicular lymphoma in adults
Administration
Diluted and given into a vein by a specialist cancer team
Important risks
Cytokine release syndrome, neurological toxicity, infection and blood-cell abnormalities
What is mosunetuzumab used for?
Mosunetuzumab is licensed as monotherapy for:
Adults with relapsed or refractory follicular lymphoma who have received at least two previous systemic therapies.
How does mosunetuzumab work?
Mosunetuzumab binds CD20 on B cells and CD3 on T cells, bringing the cells together. This activates the T cell to release substances that kill the CD20-bearing B cell, including the lymphoma cell.
mosunetuzumab preparations and strengths
Solution for infusion
Route: Intravenous
Strengths: 1 mg, 30 mg
How to take mosunetuzumab
Mosunetuzumab is not taken at home or with food. A healthcare professional dilutes it and gives it as an intravenous infusion through a dedicated line in a setting equipped to manage severe immune reactions. Patients should be adequately hydrated; corticosteroid, antihistamine and fever-reducing medicines may be given beforehand. Carry the supplied patient card at all times.
Tell the team about infections, previous recurring infections, heart, lung or kidney problems, planned vaccinations, and all medicines or supplements.
Report symptoms during the infusion and after leaving the treatment unit.
Do not drive, cycle or operate dangerous machinery if confusion, drowsiness or other neurological symptoms occur.
mosunetuzumab side effects
Common or expected effects
- Cytokine release syndrome, often involving fever or chills
- Low neutrophils, red blood cells or platelets
- Headache
- Diarrhoea
- Rash, itching or dry skin
- Low phosphate, potassium or magnesium on blood tests
- Raised liver enzymes
- Respiratory or urinary infection
Get urgent medical advice
- Cytokine release syndrome: fever, chills, low blood pressure, fast heartbeat, breathing difficulty, confusion or fainting
- ICANS neurological toxicity: new confusion, disorientation, memory problems, reduced alertness or seizures
- Serious infection or febrile neutropenia
- Tumour lysis syndrome, which can cause abnormal blood salts, kidney injury, irregular heartbeat or seizures
- Haemophagocytic lymphohistiocytosis, particularly when fever or suspected cytokine release syndrome is prolonged or atypical
- Tumour flare causing worsening swelling, pain, chest symptoms or pressure near a vital organ
mosunetuzumab in pregnancy
Human pregnancy data are unavailable, and mosunetuzumab is not recommended during pregnancy unless the specialist concludes that the expected benefit outweighs the potential fetal risk. Tell the cancer team immediately about pregnancy or plans for pregnancy. Effective contraception is advised during treatment and for at least three months after the final infusion.
mosunetuzumab while breastfeeding
It is unknown whether mosunetuzumab enters human milk, and a risk to a breastfed infant cannot be excluded. The product information advises not breastfeeding during treatment and for at least three months afterwards; discuss feeding plans with the oncology and maternity teams.
mosunetuzumab interactions
Formal interaction studies have not been performed. Give the cancer team a complete list of prescribed, non-prescription and herbal products.
Warfarin
Temporary cytokine changes may alter CYP450 activity, so anticoagulant effect may require closer monitoring when mosunetuzumab is started.
Voriconazole
Exposure may change temporarily; therapeutic monitoring should be considered where available.
Cyclosporine and other narrow-therapeutic-index CYP450 substrates
Clinical effect or blood concentrations may change temporarily and should be monitored.
Common questions about mosunetuzumab
Answers are fully visible for fast scanning and source review.
Is mosunetuzumab chemotherapy?
No. It is a targeted bispecific antibody that recruits T cells to kill CD20-positive B cells, although it is still a systemic anticancer treatment with potentially serious adverse effects.
Who can receive mosunetuzumab for follicular lymphoma?
Its licence covers adults whose follicular lymphoma has returned or not responded after at least two previous systemic treatments.
How is mosunetuzumab given?
It is diluted and given into a vein by a specialist cancer team; it is not taken by mouth or administered at home.
Sources
These sources were used to prepare and review this medicine page.
Prepared and reviewed by the iatroX editorial team.