Lunsumio (mosunetuzumab or mosunetuzumab-axgb) is an injection used to treat adults with follicular lymphoma that has come back or didn’t respond after at least two other treatments. As a bispecific antibody, it helps your immune system find and destroy cancer cells. The medication is given as an intravenous (IV) infusion by a healthcare professional in a clinic or hospital. Common side effects include rash, tiredness, headache, and a serious reaction called cytokine release syndrome (CRS).
Lunsumio (mosunetuzumab) is a bispecific T-cell engager (BiTE), which is a type of monoclonal antibody that’s designed to bind to two different targets. One side of the antibody attaches to CD20, a protein on cancer cells, while the other side binds to CD3, a protein on T-cells in your immune system. By connecting these two cells, Lunsumio (mosunetuzumab) brings T-cells close to the cancer cells, helping the immune system attack and destroy the cancer cells.
The following side effects may get better over time as your body gets used to the medication. Let your healthcare provider know immediately if you continue to experience these symptoms or if they worsen over time.
Contact your healthcare provider immediately if you experience any of the following.
Side effects that you should report to your care team as soon as possible:
Side effects that usually do not require medical attention (report these to your care team if they continue or are bothersome):
Yes. The FDA approved Lunsumio (mosunetuzumab) in 2022 under an accelerated process to treat relapsed and refractory follicular lymphoma after at least two other therapies. Additional studies are needed to confirm how well the medication works.
No. Lunsumio (mosunetuzumab) isn’t considered chemotherapy because it works differently. Chemotherapy attacks any cell that grows very quickly, while Lunsumio (mosunetuzumab) is an immunotherapy. It only binds to certain proteins on cancer and immune cells, helping your immune system specifically attack the cancer cells.
Pretty well. In a clinical study, 80% of people who received Lunsumio (mosunetuzumab) had their cancer shrink significantly or go away (overall response rate), and about 60% of them had a complete response, meaning no signs of cancer were found. Talk to your oncologist if you have questions about how well this medication might work for you.
How long you receive Lunsumio (mosunetuzumab) depends on how well it works for you and whether you have any side effects. If you tolerate the medication well and the cancer is completely gone (complete response), your oncologist might recommend stopping after 8 cycles. If the medication is helping but you don’t have a complete response by the 8th cycle, your oncologist might recommend continuing for up to 17 cycles total. But If you have any serious side effects, you might need to pause or stop treatment.
You can receive Lunsumio (mosunetuzumab) in a clinic, infusion center, or hospital. But you don’t need to be hospitalized when starting treatment unless your condition worsens or you have serious side effects like cytokine release syndrome (CRS). In some cases, hospitalization might be required to manage these specific side effects.
Lunsumio (mosunetuzumab) can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.
Lunsumio (mosunetuzumab) can cause a serious condition called cytokine release syndrome (CRS). This happens when your body’s immune system overreacts to the medication. Symptoms of CRS include headache, chills, fever, low blood pressure, trouble breathing, fast heartbeat, and confusion. CRS is most likely to happen during the first cycle, usually starting within a few hours to a few days after the infusion.
To reduce your risk, you’ll take premedications and follow a “step-up” dosing process. Tell your care team right away if you notice any symptoms. If you develop mild CRS, you might be able to restart Lunsumio (mosunetuzumab) after symptoms go away. But if the symptoms are severe, you might have to stop the medication altogether. Avoid driving or using heavy machinery until the symptoms go away.
Some people receiving Lunsumio (mosunetuzumab) developed nervous system problems. These can be mild, like headache, dizziness, or numbness in the fingers and toes, or serious, such as a condition called immune effector-cell associated neurotoxicity syndrome (ICANS). In clinical studies, ICANS occurred anywhere from the day after the infusion to about a month and a half later. Tell your care team immediately if you have symptoms like confusion, trouble speaking, shakiness, sleepiness, trouble writing, or seizures. You might need to pause treatment while your oncologist looks into it. Depending on how serious the side effect is, you might be able to restart the medication or stop it completely.
People taking Lunsumio (mosunetuzumab) have serious developed infections, including opportunistic infections. Opportunistic infections are infections that happen in people with immune systems that don’t work as well, like those with cancer or HIV. Infections can happen at any time after starting Lunsumio (mosunetuzumab). Don’t take this medication if you have an active infection. Contact your oncologist right away if you have any signs or symptoms of an infection, such as fever, chills, cough, or body aches.
Lunsumio (mosunetuzumab) can cause a life-threatening condition called hemophagocytic lymphohistiocytosis (HLH), where your immune system becomes overactive. Your oncologist will monitor you for HLH, especially if CRS lasts longer than expected. Signs and symptoms include fever, easy bruising, liver problems, low blood cell counts, and enlarged spleen. If HLH is suspected, your oncologist might pause Lunsumio (mosunetuzumab) and begin treatment for HLH right away.
Lunsumio (mosunetuzumab) commonly causes low blood cell counts, including white blood cells, red blood cells, and platelets. Low white blood cells make it harder to fight infections, low red blood cells can make you feel tired, and low platelets raise your risk of bleeding. If you have any unexplained bruising, blood in your urine, blood in your stool, or nosebleeds contact your care team right away.
Your oncologist will monitor your blood counts during treatment. If your blood cell levels drop too much, they might pause or stop Lunsumio (mosunetuzumab). You might also receive medications to help your body make more white blood cells.
Rarely, some people taking Lunsumio (mosunetuzumab) developed tumor flare, a condition that causes swelling and pain at the tumor site. For lymphoma, this might mean swelling and pain around lymph nodes. This is thought to happen because immune cells build up at the tumor site. It doesn’t mean your cancer is growing, but can cause temporary symptoms. If you notice new pain or swelling after starting Lunsumio (mosunetuzumab), contact your oncologist.
Based on the way Lunsumio (mosunetuzumab) works, it might cause harm to an unborn baby. If you’re able to get pregnant, use birth control while taking this medication and for 3 months after the last dose. Let your oncologist know if you’re pregnant or thinking about becoming pregnant while taking Lunsumio (mosunetuzumab).
The dosing follows a “step-up” schedule. Each dose is given as an intravenous (IV) infusion, starting with a low dose and increasing to the highest dose. Starting from Cycle 3, a maintenance dose of 30 mg is given. Each treatment cycle lasts 21 days.