Mosunetuzumab: Drug information

For additional information see "Mosunetuzumab: Patient drug information"

For abbreviations, symbols, and age group definitions show table

ALERT: US Boxed Warning

Cytokine release syndrome:

Cytokine release syndrome (CRS), including serious or life-threatening reactions, can occur in patients receiving mosunetuzumab. Initiate treatment with the mosunetuzumab step-up dosing schedule to reduce the risk of CRS. Withhold mosunetuzumab until CRS resolves or permanently discontinue based on severity.

Brand Names: US

Lunsumio

Pharmacologic Category

Antineoplastic Agent, Anti-CD20;
Antineoplastic Agent, Anti-CD3;
Antineoplastic Agent, Bispecific T Cell Engager;
Antineoplastic Agent, Monoclonal Antibody

Dosing: Adult

Dosage guidance:

Safety: Ensure patients are well hydrated prior to mosunetuzumab initiation. Do not administer to patients with active infection.

Premedication: Premedicate prior to each dose in cycle 1 and cycle 2; administer in cycle 3 and beyond if patient experienced cytokine release syndrome (any grade) with the previous dose. Premedication should include a corticosteroid (dexamethasone 20 mg IV or methylprednisolone 80 mg IV) completed at least 1 hour prior to mosunetuzumab infusion, an antihistamine (diphenhydramine 50 to 100 mg [or equivalent] orally or IV) at least 30 minutes prior to mosunetuzumab infusion, and an antipyretic (acetaminophen 500 to 1,000 mg orally) at least 30 minutes prior to mosunetuzumab infusion.

Clinical considerations : Administer prophylactic antimicrobials according to local practice guidelines. Consider prophylactic granulocyte colony-stimulating factor administration, as appropriate.

Follicular lymphoma, relapsed or refractory

Follicular lymphoma, relapsed or refractory: IV:

**Mosunetuzumab Dosing Schedule^{a, b}(21-Day Treatment Cycles)**
Cycle number	Day of treatment	Mosunetuzumab dose	Infusion duration
^a Administer for 8 cycles (in the absence of disease progression or unacceptable toxicity); no further treatment is required after 8 cycles if complete response is achieved. For patients achieving a partial response or with stable disease in response to treatment after 8 cycles, an additional 9 cycles (for a total of 17 cycles) should be administered (in the absence of disease progression or unacceptable toxicity).
^b Budde 2022; Sehn 2024; manufacturer’s labeling.
Cycle 1	Day 1	1 mg IV	At least 4 hours
	Day 8	2 mg IV	At least 4 hours
	Day 15	60 mg IV	At least 4 hours
Cycle 2	Day 1	60 mg IV	Infuse over 2 hours if cycle 1 infusions were well-tolerated
Cycle 3 and beyond^a	Day1	30 mg IV

**Recommendations for Restarting Mosunetuzumab After a Dosing Delay**
Last dose administered	Time since last dose	Action for next mosunetuzumab dose
^a For the day 1, day 8, and day 15 doses in the next cycle, administer premedications for all patients as per the premedication instructions above.
Cycle 1, day 1 (1 mg)	1 to 2 weeks	Administer 2 mg (cycle 1, day 8), then resume the planned treatment schedule.
Cycle 1, day 1 (1 mg)	>2 weeks	Repeat 1 mg (cycle 1, day 1), then administer 2 mg (cycle 1, day 8) and resume the planned treatment schedule.
Cycle 1, day 8 (2 mg)	1 to 2 weeks	Administer 60 mg (cycle 1, day 15), then resume the planned treatment schedule.
	>2 weeks to <6 weeks	Repeat 2 mg (cycle 1, day 8), then administer 60 mg (cycle 1, day 15) and resume the planned treatment schedule.
	≥6 weeks	Repeat 1 mg (cycle 1, day 1) and 2 mg (cycle 1, day 8), then administer 60 mg (cycle 1, day 15) and resume the planned treatment schedule.
Cycle 1, day 15 (60 mg)	1 week to <6 weeks	Administer 60 mg (cycle 2, day 1), then resume the planned treatment schedule.
Cycle 1, day 15 (60 mg)	≥6 weeks	Repeat 1 mg (cycle 2, day 1) and 2 mg (cycle 2, day 8), then administer 60 mg (cycle 2, day 15), followed by 30 mg (cycle 3, day 1), and then resume the planned treatment schedule.
Cycle 2, day 1 (60 mg)	3 weeks to <6 weeks	Administer 30 mg (cycle 3, day 1), then resume the planned treatment schedule.
Cycle 2, day 1 (60 mg)	≥6 weeks	Repeat 1 mg (cycle 3, day 1) and 2 mg (cycle 3, day 8), then administer 30 mg (cycle 3, day 15)^a, followed by 30 mg (cycle 4, day 1), and then resume the planned treatment schedule.
Cycle 3 and beyond (30 mg)	3 weeks to <6 weeks	Administer 30 mg, then resume the planned treatment schedule.
Cycle 3 and beyond (30 mg)	≥6 weeks	Repeat 1 mg on day 1 and 2 mg on day 8 during the next cycle, then administer 30 mg on day 15^a, followed by 30 mg on day 1 of subsequent cycles.

Dosage adjustment for concomitant therapy: Significant drug interactions exist, requiring dose/frequency adjustment or avoidance. Consult drug interactions database for more information.

Dosing: Kidney Impairment: Adult

Note: Kidney function estimated using the Cockcroft-Gault equation.

CrCl 30 to 89 mL/minute: There are no dosage adjustments provided in the manufacturer’s labeling; however, no clinically significant difference in mosunetuzumab pharmacokinetics was observed based on CrCl 30 to 89 mL/minute.

CrCl <30 mL/minute: There are no dosage adjustments provided in the manufacturer’s labeling (effects on mosunetuzumab pharmacokinetics are unknown).

Dosing: Liver Impairment: Adult

Mild impairment (total bilirubin ≤ ULN with AST > ULN or total bilirubin >1 to 1.5 times ULN with any AST): There are no dosage adjustments provided in the manufacturer’s labeling; however, no clinically significant difference in mosunetuzumab pharmacokinetics was observed based on mild hepatic impairment.

Moderate or severe impairment (total bilirubin >1.5 times ULN with any AST): There are no dosage adjustments provided in the manufacturer’s labeling (effects on mosunetuzumab pharmacokinetics are unknown).

Dosing: Obesity: Adult

American Society of Clinical Oncology guidelines for appropriate systemic therapy dosing in adults with cancer with a BMI ≥30 kg/m²: The dosing in the FDA-approved prescribing information should be followed in all patients, regardless of obesity status. If a patient with a BMI ≥30 kg/m² experiences high-grade toxicity from systemic anticancer therapy, the same dosage modification recommendations should be followed for all patients, regardless of obesity status (Ref).

Dosing: Adjustment for Toxicity: Adult

Cytokine release syndrome: If cytokine release syndrome (CRS) is suspected, interrupt mosunetuzumab until resolved; manage according to the table below and per clinical practice guidelines. Evaluate for and treat other causes of fever, hypoxia, and hypotension. Supportive therapy for CRS may include intensive care for severe or life-threatening CRS. If CRS is refractory to management, consider other causes, including hemophagocytic lymphohistiocytosis.

**Mosunetuzumab-Related CRS Management**
CRS grade	Symptoms	Actions
^aFever may be masked by antipyretics or anticytokine therapy; if clinical presentation is consistent with CRS, follow CRS management recommendations.
^bRefer to "Dosing: Adult" for recommended premedications and for recommendations on restarting mosunetuzumab after dose delays.
Grade 1	Temperature ≥38°C (≥100.4°F)^a, attributed to CRS	Withhold current mosunetuzumab infusion and manage per practice guidelines. If symptoms resolve, restart infusion at the same rate. Ensure CRS symptoms are resolved for at least 72 hours prior to the next mosunetuzumab dose.^b Administer premedication^b prior to the next mosunetuzumab dose and monitor more frequently.
Grade 2	Temperature ≥38°C (≥100.4°F)^awith: hypotension not requiring vasopressors and/or hypoxia requiring low-flow oxygen (<6 L/minute) via nasal cannula or blow-by	Withhold current mosunetuzumab infusion and manage per practice guidelines. If symptoms resolve, restart infusion at the 50% rate. Ensure CRS symptoms are resolved for at least 72 hours prior to the next mosunetuzumab dose.^b Administer premedication^b prior to the next mosunetuzumab dose and consider infusing the next dose at 50% rate. For the next dose, monitor more frequently and consider hospitalization.
Grade 2, recurrent		Manage per grade 3 CRS
Grade 3	Temperature ≥38°C (≥100.4°F)^a with: hypotension requiring a vasopressor (with or without vasopressin) and/or hypoxia requiring high-flow oxygen (≥6 L/minute) via nasal cannula, face mask, non-rebreather mask, or Venturi mask	Withhold mosunetuzumab and manage per practice guidelines and provide supportive therapy, which may include intensive care. Ensure CRS symptoms are resolved for at least 72 hours prior to the next mosunetuzumab dose.^b Administer premedication^b prior to the next mosunetuzumab dose and infuse the next dose at 50% rate. Hospitalize for the next mosunetuzumab dose.
Grade 3, recurrent		Permanently discontinue mosunetuzumab. Manage CRS per practice guidelines and provide supportive therapy, which may include intensive care.
Grade 4	Temperature ≥38°C (≥100.4°F)^a with: hypotension requiring multiple vasopressors (excluding vasopressin) and/or hypoxia requiring oxygen via positive pressure (eg, continuous positive airway pressure [CPAP], bilevel positive airway pressure [BiPAP], intubation, and mechanical ventilation)	Permanently discontinue mosunetuzumab. Manage CRS per practice guidelines and provide supportive therapy, which may include intensive care.

Neurologic toxicity: Interrupt mosunetuzumab at the first sign of neurologic toxicity, including immune effector cell-associated neurotoxicity syndrome (ICANS), and based on the type of neurotoxicity and the severity, consider neurology evaluation to rule out other causes of neurologic symptoms. Provide supportive therapy, which may include intensive care.

**Mosunetuzumab-Related Neurologic Toxicity Management (Including ICANS)**
Adverse reaction	Severity	Actions
^a Refer to "Dosing: Adult" for recommendations on restarting mosunetuzumab after dose delays.
Neurologic toxicity (including ICANS)	Grade 1	Continue mosunetuzumab and monitor neurologic toxicity symptoms. If ICANS, manage per practice guidelines.
	Grade 2	Withhold mosunetuzumab until neurologic toxicities/symptoms improve to grade 1 or baseline for at least 72 hours.^a Provide supportive therapy and consider neurologic evaluation. If ICANS, manage per practice guidelines.
	Grade 3	Withhold mosunetuzumab until neurologic toxicities/symptoms improve to grade 1 or baseline for at least 72 hours.^a Provide supportive therapy, which may include intensive care; consider neurology evaluation. If ICANS, manage per practice guidelines. If recurrence of ICANS, permanently discontinue mosunetuzumab.
	Grade 4	Permanently discontinue mosunetuzumab. Provide supportive therapy, which may include intensive care; consider neurology evaluation. If ICANS, manage per practice guidelines.

**Recom** **mended Mosunetuzumab Dosage Modifications for Other Adverse Reactions**
Adverse reaction	Severity	Actions
^a Refer to "Dosing: Adult" for recommendations on restarting mosunetuzumab after dose delays.
^b HLH = hemophagocytic lymphohistiocytosis.
Hematologic toxicity	ANC <500/mm³	Withhold mosunetuzumab until ANC is ≥500/mm³.^a Consider prophylactic granulocyte colony-stimulating factor administration as appropriate.
Hematologic toxicity	Other cytopenias	Temporarily withhold or permanently discontinue mosunetuzumab based on the severity.
HLH^b	Suspected	Interrupt mosunetuzumab and evaluate promptly. Manage promptly per current HLH practice guidelines.
Infections	Grades 1 to 4	Manage infection appropriately and as clinically indicated. Withhold mosunetuzumab in patients with active infection until infection resolves.^a For grade 4 infection, consider permanently discontinuing mosunetuzumab.
Compression or obstruction due to tumor flare	Any	Institute standard treatment as clinically indicated.
Other adverse reactions	Grade 3 or higher	Withhold mosunetuzumab until adverse reaction resolves to grade 1 or baseline.^a

Dosing: Older Adult

Refer to adult dosing.

Adverse Reactions

The following adverse drug reactions and incidences are derived from product labeling unless otherwise specified. Adverse reactions reported in adults.

>10%:

Cardiovascular: Edema (17%)

Dermatologic: Pruritus (21%), skin rash (39%), xeroderma (16%)

Endocrine & metabolic: Decreased serum magnesium (34%), decreased serum phosphate (78%), decreased serum potassium (33%), increased serum glucose (42%), increased uric acid (22%)

Gastrointestinal: Abdominal pain (12%), diarrhea (17%), nausea (17%)

Hematologic & oncologic: Decreased hemoglobin (68%; grades 3/4: 12%), decreased neutrophils (58%; grades 3/4: 40%), decreased platelet count (46%; grades 3/4: 10%), decreased white blood cell count (60%; grades 3/4: 13%), lymphocytopenia (100%; grades 3/4: 98%)

Hepatic: Increased gamma-glutamyl transferase (34%), increased serum alanine aminotransferase (32%), increased serum aspartate aminotransferase (39%)

Hypersensitivity: Cytokine release syndrome (44%)

Nervous system: Chills (13%), dizziness (12%), fatigue (42%), headache (32%), insomnia (12%), peripheral neuropathy (20%)

Neuromuscular & skeletal: Arthralgia (11%), musculoskeletal pain (28%)

Respiratory: Cough (22%), dyspnea (11%), upper respiratory tract infection (14%)

Miscellaneous: Fever (29%)

1% to 10%:

Dermatologic: Exfoliation of skin (10%)

Genitourinary: Urinary tract infection (10%)

Hematologic & oncologic: Tumor flare (<10%), tumor lysis syndrome (<10%)

Infection: Epstein-Barr infection (<10%), sepsis (<10%)

Nervous system: Anxiety (<10%), mental status changes (<10%; including cognitive dysfunction, confusion, delirium, disturbance in attention, drowsiness, encephalopathy), motor dysfunction (<10%; including abnormal gait, ataxia, tremor), neurotoxicity (immune effector cell-associated neurotoxicity syndrome [ICANS]: <10%)

Renal: Kidney impairment (<10%)

Respiratory: Pneumonia (<10%)

Frequency not defined:

Hematologic & oncologic: Febrile neutropenia, hemophagocytic lymphohistiocytosis

Infection: Serious infection (including opportunistic infection)

Contraindications

There are no contraindications listed in the manufacturer's labeling.

Warnings/Precautions

Concerns related to adverse effects:

• Cytokine release syndrome: Mosunetuzumab may cause cytokine release syndrome (CRS), including serious or life-threatening reactions. In the clinical trial, CRS occurred in over one-third of patients who received mosunetuzumab; grade 1 occurred in 28%, grade 2 in 15%, grade 3 in 2%, and grade 4 in <1% of patients. Recurrent CRS has been reported. Most patients experienced CRS following the initial dose on day 1 of cycle 1, day 8 of cycle 1, and day 15 of cycle 1; CRS has also been observed with subsequent doses. The median time to onset of CRS from the start of administration on day 1 of cycle 1 was 5 hours (range: 1 hour to 3 days); the onset with subsequent doses was 25 to 46 hours (range: up to 16 days). The median duration of CRS was 3 days (range: 1 to 29 days). Clinical signs/symptoms of CRS included (but were not limited to) fever, chills, hypotension, tachycardia, hypoxia, and headache. Concurrent neurologic adverse reactions occurred in some patients and included (but were not limited to) headache, confusion, and anxiety. Patients who experience CRS (or other adverse reactions that impair consciousness) should be evaluated and advised not to drive and to refrain from operating heavy/potentially dangerous machinery until resolution.

• Cytopenias: Mosunetuzumab may cause serious or severe cytopenias (including neutropenia, anemia, and thrombocytopenia). Grade 3 and 4 events have been commonly reported; neutropenic fever occurred in a small percentage of patients.

• Hemophagocytic lymphohistiocytosis: Mosunetuzumab may cause serious or fatal hemophagocytic lymphohistiocytosis (HLH). HLH is a potentially life-threatening, hyperinflammatory syndrome that is independent of CRS. Common HLH manifestations include fever, elevated ferritin, hemophagocytosis, cytopenias, coagulopathy, hepatitis, and splenomegaly. HLH occurred in a small number of patients and most cases were identified within the first 28 days following mosunetuzumab initiation, with a few of those cases preceded by diagnosed or suspected CRS. Some HLH cases occurred with concurrent Epstein-Barr virus (EBV) and/or cytomegalovirus infection. Consider HLH when CRS presents as atypical or prolonged, or if macrophage activation features are present.

• Infections: Mosunetuzumab may cause serious or fatal infections, including opportunistic infections. The most common grade 3 or higher infections were pneumonia, sepsis, and upper respiratory tract infection. Mosunetuzumab should not be administered in the presence of active infection; use caution if considering mosunetuzumab in patients with a history of recurring or chronic infections (eg, chronic, active EBV), with underlying conditions that may predispose to infections, or who have had significant prior immunosuppressive treatment.

• Neurologic toxicity: Mosunetuzumab may cause serious and life-threatening neurologic toxicity, including immune effector cell-associated neurotoxicity syndrome (ICANS). Neurologic toxicity occurred in over one-third of patients who received mosunetuzumab; grade 3 neurologic toxicity was observed in a small percentage of patients. The most frequent neurologic toxicities were headache, peripheral neuropathy, dizziness, and mental status changes (including confusion, attention disturbance, cognitive disorder, delirium, encephalopathy, and somnolence). ICANS was reported in a small percentage of patients, usually grade 1 and 2, and rarely grade 3 events. ICANS typically occurred during cycle 1, with a median time to onset of 17 days (range: 1 to 48 days). ICANS resolved in a majority of cases; the median duration was 3 days (range: 1 to 20 days). The most frequent manifestations of ICANS were confusion and lethargy. Coadministration of mosunetuzumab with other products that cause dizziness or mental status changes may increase the risk of neurologic toxicity. Patients who experience neurologic toxicity (eg, tremors, dizziness, insomnia, severe neurotoxicity) or any other adverse reactions that impair consciousness should be evaluated, including potential neurology evaluation, and patients at increased risk should be advised not to drive and to refrain from operating heavy/potentially dangerous machinery until resolution.

• Tumor flare: Mosunetuzumab may cause serious or severe tumor flare; tumor flare occurred in a small percentage of treated patients. Tumor flare manifestations include new or worsening pleural effusions, localized pain/swelling at lymphoma lesion sites, and tumor inflammation. Patients with bulky tumors or disease located in close proximity to airways or a vital organ may be at risk for complications.

Dosage Forms: US

Excipient information presented when available (limited, particularly for generics); consult specific product labeling.

Solution, Intravenous [preservative free]:

Lunsumio: Mosunetuzumab-axgb 1 mg/mL (1 mL); Mosunetuzumab-axgb 30 mg/30 mL (30 mL)

Generic Equivalent Available: US

Pricing: US

Solution (Lunsumio Intravenous)

1 mg/mL (per mL): $749.10

30 mg/30 mL (per mL): $749.11

Disclaimer: A representative AWP (Average Wholesale Price) price or price range is provided as reference price only. A range is provided when more than one manufacturer's AWP price is available and uses the low and high price reported by the manufacturers to determine the range. The pricing data should be used for benchmarking purposes only, and as such should not be used alone to set or adjudicate any prices for reimbursement or purchasing functions or considered to be an exact price for a single product and/or manufacturer. Medi-Span expressly disclaims all warranties of any kind or nature, whether express or implied, and assumes no liability with respect to accuracy of price or price range data published in its solutions. In no event shall Medi-Span be liable for special, indirect, incidental, or consequential damages arising from use of price or price range data. Pricing data is updated monthly.

Prescribing and Access Restrictions

Mosunetuzumab is available through authorized specialty distributors. Distribution information is available at https://www.genentech-access.com/hcp/brands/lunsumio/learn-about-our-services/product-distribution.html.

Administration: Adult

IV: Infuse over at least 4 hours in cycle 1; if cycle 1 infusions are tolerated, infuse over 2 hours in cycle 2 and beyond. Do not infuse through an inline filter, although drip chamber filters may be used to administer mosunetuzumab. For IV infusion only. Do not infuse other medications through the same IV line. Administer in a facility with appropriate support to manage severe reactions, such as cytokine release syndrome and neurotoxicity.

No incompatibilities have been observed with infusion sets or infusion aids with products containing materials of polyvinyl chloride (PVC), polyolefin, polyurethane, polybutadiene, silicone, acrylonitrile butadiene styrene, polycarbonate, polyetherurethane, fluorinated ethylene propylene, polytetrafluorethylene, or with drip chamber filter membrane composed of polyamide.

Premedicate prior to each dose in cycle 1 and cycle 2; administer in cycle 3 and beyond if patient experienced cytokine release syndrome (any grade) with the previous dose. Premedication should include a corticosteroid (dexamethasone 20 mg IV or methylprednisolone 80 mg IV) completed at least 1 hour prior to mosunetuzumab infusion, an antihistamine (diphenhydramine 50 to 100 mg [or equivalent] orally or IV) at least 30 minutes prior to mosunetuzumab infusion, and an antipyretic (acetaminophen 500 to 1,000 mg orally) at least 30 minutes prior to mosunetuzumab infusion.

Medication Guide and/or Vaccine Information Statement (VIS)

An FDA-approved patient medication guide, which is available with the product information and as follows, must be dispensed with this medication:

Lunsumio: https://www.accessdata.fda.gov/drugsatfda_docs/label/2024/761263s005lbl.pdf#page=19

Use: Labeled Indications

Follicular lymphoma, relapsed or refractory: Treatment of relapsed or refractory follicular lymphoma in adults after ≥2 lines of systemic therapy.

Medication Safety Issues

Sound-alike/look-alike issues:

Mosunetuzumab may be confused with epcoritamab, margetuximab, mirvetuximab soravtansine, mogamulizumab, zenocutuzumab.

High alert medication:

The Institute for Safe Medication Practices (ISMP) includes this medication among its list of drug classes (chemotherapeutic agent, parenteral and oral) which have a heightened risk of causing significant patient harm when used in error (High-Alert Medications in Acute Care, Community/Ambulatory Care, and Long-Term Care Settings).

Metabolism/Transport Effects

None known.

Drug Interactions

Note: Interacting drugs may not be individually listed below if they are part of a group interaction (eg, individual drugs within “CYP3A4 Inducers [Strong]” are NOT listed). For a complete list of drug interactions by individual drug name and detailed management recommendations, use the drug interactions program by clicking on the “Launch drug interactions program” link above.

5-Aminosalicylic Acid Derivatives: May increase myelosuppressive effects of Myelosuppressive Agents. Risk C: Monitor

Abrocitinib: May increase immunosuppressive effects of Immunosuppressants (Miscellaneous Oncologic Agents). Risk X: Avoid

Antithymocyte Globulin (Equine): Anti-CD20 B-Cell Depleting Therapies may increase adverse/toxic effects of Antithymocyte Globulin (Equine). Specifically, these effects may be unmasked if the dose of anti-CD20 B-cell depleting therapy is reduced. Anti-CD20 B-Cell Depleting Therapies may increase immunosuppressive effects of Antithymocyte Globulin (Equine). Specifically, infections may occur with greater severity and/or atypical presentations. Risk C: Monitor

Antithymocyte Globulin (Equine): Immunosuppressants (Miscellaneous Oncologic Agents) may increase adverse/toxic effects of Antithymocyte Globulin (Equine). Specifically, these effects may be unmasked if the dose of immunosuppressive therapy is reduced. Immunosuppressants (Miscellaneous Oncologic Agents) may increase immunosuppressive effects of Antithymocyte Globulin (Equine). Specifically, infections may occur with greater severity and/or atypical presentations. Risk C: Monitor

Antithyroid Agents: Myelosuppressive Agents may increase neutropenic effects of Antithyroid Agents. Risk C: Monitor

Baricitinib: Immunosuppressants (Miscellaneous Oncologic Agents) may increase immunosuppressive effects of Baricitinib. Risk X: Avoid

BCG Products: Anti-CD20 B-Cell Depleting Therapies may increase adverse/toxic effects of BCG Products. Specifically, the risk of vaccine-associated infection may be increased. Anti-CD20 B-Cell Depleting Therapies may decrease therapeutic effects of BCG Products. Risk X: Avoid

Brincidofovir: Immunosuppressants (Miscellaneous Oncologic Agents) may decrease therapeutic effects of Brincidofovir. Risk C: Monitor

Brivudine: May increase adverse/toxic effects of Immunosuppressants (Miscellaneous Oncologic Agents). Risk X: Avoid

Chikungunya Vaccine (Live): Anti-CD20 B-Cell Depleting Therapies may decrease therapeutic effects of Chikungunya Vaccine (Live). Anti-CD20 B-Cell Depleting Therapies may increase adverse/toxic effects of Chikungunya Vaccine (Live). Specifically, the risk of vaccine-associated infection may be increased. Risk X: Avoid

Chikungunya Vaccine (Live): Immunosuppressants (Miscellaneous Oncologic Agents) may increase adverse/toxic effects of Chikungunya Vaccine (Live). Specifically, the risk of vaccine-associated infection may be increased. Immunosuppressants (Miscellaneous Oncologic Agents) may decrease therapeutic effects of Chikungunya Vaccine (Live). Risk X: Avoid

Chloramphenicol (Ophthalmic): May increase adverse/toxic effects of Myelosuppressive Agents. Risk C: Monitor

Chloramphenicol (Systemic): Myelosuppressive Agents may increase myelosuppressive effects of Chloramphenicol (Systemic). Risk X: Avoid

Cladribine: Immunosuppressants (Miscellaneous Oncologic Agents) may increase immunosuppressive effects of Cladribine. Risk X: Avoid

CloZAPine: Myelosuppressive Agents may increase adverse/toxic effects of CloZAPine. Specifically, the risk for neutropenia may be increased. Risk C: Monitor

Coccidioides immitis Skin Test: Coadministration of Immunosuppressants (Miscellaneous Oncologic Agents) and Coccidioides immitis Skin Test may alter diagnostic results. Management: Consider discontinuing these oncologic agents several weeks prior to coccidioides immitis skin antigen testing to increase the likelihood of accurate diagnostic results. Risk D: Consider Therapy Modification

COVID-19 Vaccines: Anti-CD20 B-Cell Depleting Therapies may decrease therapeutic effects of COVID-19 Vaccines. Management: Administer COVID-19 vaccine 2 to 4 weeks prior to the next scheduled dose of anti-CD20 therapy, if used chronically for the treatment of autoimmune disease. Revaccinate 6 months after completion of anti-CD20 therapy if used over a limited period. Risk D: Consider Therapy Modification

CYP Substrates (Narrow Therapeutic Index/Sensitive with Inhibitors): Mosunetuzumab may increase serum concentration of CYP Substrates (Narrow Therapeutic Index/Sensitive with Inhibitors). Risk C: Monitor

Deferiprone: Myelosuppressive Agents may increase neutropenic effects of Deferiprone. Management: Avoid the concomitant use of deferiprone and myelosuppressive agents whenever possible. If this combination cannot be avoided, monitor the absolute neutrophil count more closely. Risk D: Consider Therapy Modification

Dengue Tetravalent Vaccine (Live): Anti-CD20 B-Cell Depleting Therapies may increase adverse/toxic effects of Dengue Tetravalent Vaccine (Live). Specifically, the risk of vaccine-associated infection may be increased. Anti-CD20 B-Cell Depleting Therapies may decrease therapeutic effects of Dengue Tetravalent Vaccine (Live). Risk X: Avoid

Denosumab: May increase immunosuppressive effects of Immunosuppressants (Miscellaneous Oncologic Agents). Management: Consider the risk of serious infections versus the potential benefits of coadministration of denosumab and immunosuppressants. If combined, monitor patients for signs/symptoms of serious infections. Risk D: Consider Therapy Modification

Deucravacitinib: May increase immunosuppressive effects of Immunosuppressants (Miscellaneous Oncologic Agents). Risk X: Avoid

Efgartigimod Alfa: May decrease therapeutic effects of Fc Receptor-Binding Agents. Risk C: Monitor

Etrasimod: May increase immunosuppressive effects of Immunosuppressants (Miscellaneous Oncologic Agents). Risk X: Avoid

Fexinidazole: Myelosuppressive Agents may increase myelosuppressive effects of Fexinidazole. Risk X: Avoid

Filgotinib: May increase immunosuppressive effects of Immunosuppressants (Miscellaneous Oncologic Agents). Risk X: Avoid

Inebilizumab: Immunosuppressants (Miscellaneous Oncologic Agents) may increase immunosuppressive effects of Inebilizumab. Risk C: Monitor

Influenza Virus Vaccines: Anti-CD20 B-Cell Depleting Therapies may decrease therapeutic effects of Influenza Virus Vaccines. Management: Administer influenza vaccines 2 weeks prior to starting anti-CD20 B-cell depleting therapies. Vaccination of patients treated with these agents in the past 6 months is not recommended. Risk D: Consider Therapy Modification

Leflunomide: Immunosuppressants (Miscellaneous Oncologic Agents) may increase immunosuppressive effects of Leflunomide. Management: Increase the frequency of chronic monitoring of platelet, white blood cell count, and hemoglobin or hematocrit to monthly, instead of every 6 to 8 weeks, if leflunomide is coadministered with immunosuppressive agents. Risk D: Consider Therapy Modification

Linezolid: May increase myelosuppressive effects of Myelosuppressive Agents. Risk C: Monitor

Mumps- Rubella- or Varicella-Containing Live Vaccines: Anti-CD20 B-Cell Depleting Therapies may increase adverse/toxic effects of Mumps- Rubella- or Varicella-Containing Live Vaccines. Specifically, the risk of vaccine-associated infection may be increased. Anti-CD20 B-Cell Depleting Therapies may decrease therapeutic effects of Mumps- Rubella- or Varicella-Containing Live Vaccines. Risk X: Avoid

Nadofaragene Firadenovec: Immunosuppressants (Miscellaneous Oncologic Agents) may increase adverse/toxic effects of Nadofaragene Firadenovec. Specifically, the risk of disseminated adenovirus infection may be increased. Risk X: Avoid

Natalizumab: Immunosuppressants (Miscellaneous Oncologic Agents) may increase immunosuppressive effects of Natalizumab. Risk X: Avoid

Nipocalimab: May decrease therapeutic effects of Fc Receptor-Binding Agents. Risk C: Monitor

Ocrelizumab: Immunosuppressants (Miscellaneous Oncologic Agents) may increase immunosuppressive effects of Ocrelizumab. Risk C: Monitor

Ofatumumab: Immunosuppressants (Miscellaneous Oncologic Agents) may increase immunosuppressive effects of Ofatumumab. Risk C: Monitor

Olaparib: Myelosuppressive Agents may increase myelosuppressive effects of Olaparib. Risk C: Monitor

Pidotimod: Immunosuppressants (Miscellaneous Oncologic Agents) may decrease therapeutic effects of Pidotimod. Risk C: Monitor

Pimecrolimus: May increase immunosuppressive effects of Immunosuppressants (Miscellaneous Oncologic Agents). Risk X: Avoid

Poliovirus Vaccine (Live/Trivalent/Oral): Anti-CD20 B-Cell Depleting Therapies may increase adverse/toxic effects of Poliovirus Vaccine (Live/Trivalent/Oral). Specifically, the risk of vaccine-associated infection may be increased. Anti-CD20 B-Cell Depleting Therapies may decrease therapeutic effects of Poliovirus Vaccine (Live/Trivalent/Oral). Risk X: Avoid

Polymethylmethacrylate: Immunosuppressants (Miscellaneous Oncologic Agents) may increase hypersensitivity effects of Polymethylmethacrylate. Management: Use caution when considering use of bovine collagen-containing implants such as the polymethylmethacrylate-based Bellafill brand implant in patients who are receiving immunosuppressants. Consider use of additional skin tests prior to administration. Risk D: Consider Therapy Modification

Promazine: May increase myelosuppressive effects of Myelosuppressive Agents. Risk C: Monitor

Rabies Vaccine: Anti-CD20 B-Cell Depleting Therapies may decrease therapeutic effects of Rabies Vaccine. Management: Complete rabies vaccination at least 2 weeks before initiation of immunosuppressant therapy if possible. If combined, check for rabies antibody titers, and if vaccination is for post exposure prophylaxis, administer a 5th dose of the vaccine. Risk D: Consider Therapy Modification

Ritlecitinib: Immunosuppressants (Miscellaneous Oncologic Agents) may increase immunosuppressive effects of Ritlecitinib. Risk X: Avoid

Ropeginterferon Alfa-2b: Myelosuppressive Agents may increase myelosuppressive effects of Ropeginterferon Alfa-2b. Management: Avoid coadministration of ropeginterferon alfa-2b and other myelosuppressive agents. If this combination cannot be avoided, monitor patients for excessive myelosuppressive effects. Risk D: Consider Therapy Modification

Rozanolixizumab: May decrease therapeutic effects of Fc Receptor-Binding Agents. Risk C: Monitor

Ruxolitinib (Topical): Immunosuppressants (Miscellaneous Oncologic Agents) may increase immunosuppressive effects of Ruxolitinib (Topical). Risk X: Avoid

Sipuleucel-T: Immunosuppressants (Miscellaneous Oncologic Agents) may decrease therapeutic effects of Sipuleucel-T. Management: Consider reducing the dose or discontinuing the use of immunosuppressants prior to initiating sipuleucel-T therapy. Risk D: Consider Therapy Modification

Sphingosine 1-Phosphate (S1P) Receptor Modulators: May increase immunosuppressive effects of Immunosuppressants (Miscellaneous Oncologic Agents). Risk C: Monitor

Tacrolimus (Topical): Immunosuppressants (Miscellaneous Oncologic Agents) may increase immunosuppressive effects of Tacrolimus (Topical). Risk X: Avoid

Talimogene Laherparepvec: Immunosuppressants (Miscellaneous Oncologic Agents) may increase adverse/toxic effects of Talimogene Laherparepvec. Specifically, the risk of infection from the live, attenuated herpes simplex virus contained in talimogene laherparepvec may be increased. Risk X: Avoid

Tertomotide: Immunosuppressants (Miscellaneous Oncologic Agents) may decrease therapeutic effects of Tertomotide. Risk X: Avoid

Tofacitinib: Immunosuppressants (Miscellaneous Oncologic Agents) may increase immunosuppressive effects of Tofacitinib. Risk X: Avoid

Typhoid Vaccine: Anti-CD20 B-Cell Depleting Therapies may increase adverse/toxic effects of Typhoid Vaccine. Specifically, the risk of vaccine-associated infection may be increased. Anti-CD20 B-Cell Depleting Therapies may decrease therapeutic effects of Typhoid Vaccine. Risk X: Avoid

Ublituximab: Immunosuppressants (Miscellaneous Oncologic Agents) may increase immunosuppressive effects of Ublituximab. Risk C: Monitor

Upadacitinib: Immunosuppressants (Miscellaneous Oncologic Agents) may increase immunosuppressive effects of Upadacitinib. Risk X: Avoid

Vaccines (Live): Anti-CD20 B-Cell Depleting Therapies may increase adverse/toxic effects of Vaccines (Live). Specifically, the risk of vaccine-associated infection may be increased. Anti-CD20 B-Cell Depleting Therapies may decrease therapeutic effects of Vaccines (Live). Risk X: Avoid

Vaccines (Non-Live/Inactivated/Non-Replicating): Anti-CD20 B-Cell Depleting Therapies may decrease therapeutic effects of Vaccines (Non-Live/Inactivated/Non-Replicating). Management: Give non-live/inactivated/non-replicating vaccines at least 2 weeks prior to initiation or 6 months after anti-CD20 B-cell depleting therapies. If vaccinated prior to B cell recovery, consider assessing immune response to vaccination. Risk D: Consider Therapy Modification

Yellow Fever Vaccine: Anti-CD20 B-Cell Depleting Therapies may increase adverse/toxic effects of Yellow Fever Vaccine. Specifically, the risk of vaccine-associated infection may be increased. Anti-CD20 B-Cell Depleting Therapies may decrease therapeutic effects of Yellow Fever Vaccine. Risk X: Avoid

Zoster Vaccine (Live/Attenuated): Anti-CD20 B-Cell Depleting Therapies may increase adverse/toxic effects of Zoster Vaccine (Live/Attenuated). Specifically, the risk of vaccine-associated infection may be increased. Anti-CD20 B-Cell Depleting Therapies may decrease therapeutic effects of Zoster Vaccine (Live/Attenuated). Risk X: Avoid

Zoster Vaccine (Live/Attenuated): Immunosuppressants (Miscellaneous Oncologic Agents) may increase adverse/toxic effects of Zoster Vaccine (Live/Attenuated). Specifically, the risk of vaccine-associated infection may be increased. Immunosuppressants (Miscellaneous Oncologic Agents) may decrease therapeutic effects of Zoster Vaccine (Live/Attenuated). Risk X: Avoid

Reproductive Considerations

Verify pregnancy status prior to treatment initiation.

Patients who could become pregnant should use effective contraception during therapy and for 3 months after the last mosunetuzumab dose.

Pregnancy Considerations

Mosunetuzumab is a humanized monoclonal antibody (IgG₁). Human IgG crosses the placenta. Fetal exposure is dependent upon the IgG subclass, maternal serum concentrations, placental integrity, newborn birth weight, and gestational age, generally increasing as pregnancy progresses. The lowest exposure would be expected during the period of organogenesis and the highest during the third trimester (Clements 2020; Palmeira 2012; Pentsuk 2009).

Animal reproduction studies have not been conducted. Based on the mechanism of action, in utero exposure to mosunetuzumab may cause B-cell lymphocytopenia in exposed infants and compromise pregnancy maintenance.

A long-term observational research study is collecting information about the diagnosis and treatment of cancer during pregnancy. For additional information about the pregnancy and cancer registry or to become a participant, contact Cooper Health (1-877-635-4499).

Breastfeeding Considerations

It is not known if mosunetuzumab is present in breast milk.

Mosunetuzumab is a humanized monoclonal antibody (IgG₁). Human IgG is present in breast milk; concentrations are dependent upon IgG subclass and postpartum age (Anderson 2021).

Due to the potential for B-cell depletion in the breastfed infant, breastfeeding is not recommended by the manufacturer during treatment and for 3 months after the last mosunetuzumab dose.

Monitoring Parameters

CBC with differential (monitor throughout treatment). Verify pregnancy status prior to treatment initiation (in patients who could become pregnant). Monitor for signs/symptoms of cytokine release syndrome (CRS) and neurologic toxicity, including immune effector cell-associated neurotoxicity syndrome (ICANS). At the first sign of CRS, immediately evaluate patients for hospitalization; if CRS occurs, monitor more frequently during subsequent doses. At the first sign of neurologic toxicity (including ICANS), immediately evaluate and consider neurology evaluation, as appropriate. Monitor hydration status. Monitor for clinical signs/symptoms of hemophagocytic lymphohistiocytosis (HLH); evaluate promptly if HLH signs/symptoms occur. Monitor for signs/symptoms of infection (including opportunistic infections) prior to and during treatment and for signs/symptoms of tumor flare, including compression or obstruction due to mass effect secondary to tumor flare; patients with bulky tumors or disease located in close proximity to airways or a vital organ should be monitored closely during initial therapy.

The American Society of Clinical Oncology hepatitis B virus (HBV) screening and management provisional clinical opinion (ASCO [Hwang 2020]) recommends HBV screening with hepatitis B surface antigen, hepatitis B core antibody, total Ig or IgG, and antibody to hepatitis B surface antigen prior to beginning (or at the beginning of) systemic anticancer therapy; do not delay treatment for screening/results. Detection of chronic or past HBV infection requires a risk assessment to determine antiviral prophylaxis requirements, monitoring, and follow-up.

Mechanism of Action

Mosunetuzumab is a T-cell engaging bispecific humanized monoclonal antibody that binds to the CD3 receptor expressed on the surface of T-cells and CD20 expressed on the surface of lymphoma cells and some healthy B-lineage cells. Mosunetuzumab activates T-cells, releasing proinflammatory cytokines, and inducing B-cell lysis.

Pharmacokinetics (Adult Data Unless Noted)

Onset: Peripheral B-cell counts decreased to undetectable levels (<5 cells/microliter) in a majority of patients by day 1 of cycle 2; B-cell depletion was sustained at later cycles, including at cycles 4 and 8. Median time to first response: 1.4 months (range: 1.1 to 8.9 months).

Distribution: V_d: 5.49 L.

Half-life elimination: ~16 days.

Excretion: Clearance: Baseline: 1.08 L/day; Steady state: 0.584 L/day.

Brand Names: International

International Brand Names by Country

For country code abbreviations (show table)

(QA) Qatar: Lunsumio

Anderson PO. Monoclonal antibodies during breastfeeding. Breastfeed Med. 2021;16(8):591-593. doi:10.1089/bfm.2021.0110 [PubMed 33956488]
Budde LE, Sehn LH, Matasar M, et al. Safety and efficacy of mosunetuzumab, a bispecific antibody, in patients with relapsed or refractory follicular lymphoma: a single-arm, multicentre, phase 2 study. Lancet Oncol. 2022;23(8):1055-1065. doi:10.1016/S1470-2045(22)00335-7 [PubMed 35803286]
Clements T, Rice TF, Vamvakas G, et al. Update on transplacental transfer of IgG subclasses: impact of maternal and fetal factors. Front Immunol. 2020;11:1920. doi:10.3389/fimmu.2020.01920 [PubMed 33013843]
Griggs JJ, Bohlke K, Balaban EP, et al. Appropriate systemic therapy dosing for obese adult patients with cancer: ASCO guideline update. J Clin Oncol. 2021:JCO2100471. doi:10.1200/JCO.21.00471 [PubMed 33939491]
Hwang JP, Feld JJ, Hammond SP, et al. Hepatitis B virus screening and management for patients with cancer prior to therapy: ASCO provisional clinical opinion update. J Clin Oncol. 2020;38(31):3698-3715. doi:10.1200/JCO.20.01757 [PubMed 32716741]
Lunsumio (mosunetuzumab) [prescribing information]. South San Francisco, CA: Genentech, Inc; November 2024.
Palmeira P, Quinello C, Silveira-Lessa AL, Zago CA, Carneiro-Sampaio M. IgG placental transfer in healthy and pathological pregnancies. Clin Dev Immunol. 2012;2012:985646. doi:10.1155/2012/985646 [PubMed 22235228]
Pentsuk N, van der Laan JW. An interspecies comparison of placental antibody transfer: new insights into developmental toxicity testing of monoclonal antibodies. Birth Defects Res B Dev Reprod Toxicol. 2009;86(4):328-344. doi:10.1002/bdrb.20201 [PubMed 19626656]
Sehn LH, Bartlett NL, Matasar MJ, et al. Long-term 3-year follow-up of mosunetuzumab in relapsed or refractory follicular lymphoma after ≥2 prior therapies. Blood. Published online October 24, 2024. doi:10.1182/blood.2024025454 [PubMed 39447094]

Topic 140391 Version 44.0

خرید پکیج

Mosunetuzumab: Drug information