Elrexfio (elranatamab or elranatamab-bcmm) is a type of monoclonal antibody known as BiTE therapy, which stands for bispecific T-cell engager. It's used to treat relapsed or advanced multiple myeloma. Elrexfio (elranatamab) is given as an injection under the skin. When you first start this medication, you'll stay in the hospital to receive the “step-up” doses so your oncologist can monitor you for serious side effects, like cytokine release syndrome. After that, you'll receive it once a week or once every two weeks. Some common side effects of Elrexfio (elranatamab) include injection site reactions, tiredness, and diarrhea.
Advanced multiple myeloma in adults who've already tried at least four other therapies
Elrexfio (elranatamab) is a bispecific T-cell engager, or BiTE therapy. This means it’s a monoclonal antibody that works by grabbing onto 2 different targets. One side of the antibody binds to a protein on the multiple myeloma cancer cells. The other side targets a type of cells in your own immune system called T-cells. By bringing these cells together, Elrexfio (elranatamab) makes it easier for the T cells to attack the cancer cells. In addition, when Elrexfio (elranatamab) binds to both cells, the multiple myeloma cancer cells can’t grow or spread as well.
Source: DailyMed
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):
Option for treating multiple myeloma that no longer responds to other treatments
Works in a targeted, more specific way than traditional chemotherapy
Given as a brief injection under the skin, so more convenient once the step-up dose process is complete
Step-up doses require several hospital visits
Given as an injection, so requires a needle
Can cause side effects such as serious infections and cytokine release syndrome
If you develop a temperature of 100.4 Fahrenheit or higher, get medical help right away. This means you have a fever. A fever with Elrexfio (elranatamab) can be serious, because it can mean you have an infection or it can be an early sign of cytokine release syndrome (CRS).
Elrexfio (elranatamab) is given as a shot underneath your skin. Sometimes, you might have a skin reaction such as redness or swelling around the area where you received the shot. This usually isn’t dangerous, but let your oncologist know if it happens. They might recommend using an ice pack to manage it.
You might experience diarrhea while taking Elrexfio (elranatamab). If you have this side effect, your oncologist might recommend you take over-the-counter medications like loperamide (Imodium A-D) to help treat it. Make sure you drink enough fluids to stay hydrated. But avoid sugary sports drinks because they can make diarrhea worse.
Elrexfio (elranatamab) can cause tiredness, especially during the step-up dosing period. This is also the most common time for nervous system side effects to happen, such as confusion and possible seizures. Because of these risks, you’re recommended to avoid driving or doing any activity that needs a lot of attention during step up dosing and for two days after you complete those doses.
Sometimes, taking Elrexfio (elranatamab) can cause irritation to your liver. Your oncologist will order regular blood tests during treatment to check your liver health. If you have stomach pain, yellowish skin, or yellow around the whites of your eyes, call your care team right away because these are symptoms of serious liver problems.
Females who are taking Elrexfio (elranatamab) should avoid breastfeeding during treatment and for 4 months after the last dose. We don’t know whether Elrexfio (elranatamab) is found in breast milk and whether it affects breastfed babies, but there’s a possible risk of harm to a baby.
Elrexfio (elranatamab) 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.
Cytokine release syndrome (CRS) is a common and potentially life-threatening side effect of Elrexfio (elranatamab). CRS happens when small immune proteins called cytokines overreact to Elrexfio (elranatamab) treatment. Most people experience CRS within the first three injections, when their oncologist is raising the dose. Symptoms of CRS can appear up to 9 days after an injection and can include headache, fever, chills. In more serious cases, CRS can lead to organ damage.
To prevent CRS, your oncologist will give you pre-treatment medications, like corticosteroids and antihistamines, before your first three doses of Elrexfio (elranatamab). To be safe, they’ll also ask you to stay in the hospital for up to two days after each of your first two doses to monitor you for symptoms and provide treatment if needed.
If you develop CRS, your oncologist will pause Elrexfio (elranatamab). Depending on how severe your symptoms are, sometimes you can restart Elrexfio (elranatamab) when you get better. But, other times, your oncologist will ask you to stop Elrexfio (elranatamab) altogether.
Some people taking Elrexfio (elranatamab) developed nervous system problems. These problems can be mild, such as headache or numbness in the fingers. In rare, but more serious cases, people have developed a condition called immune effector-cell associated neurotoxicity syndrome (ICANS) with symptoms such as trouble waking up, confusion, agitation, or hallucination. Typically, symptoms of ICANS show up during the first few doses of Elrexfio (elranatamab), up to 4 days after the dose. Because of the risk of serious harm, don’t drive or do anything that needs a lot of attention in the days right after your step-up doses.
If you experience any of these symptoms, seek medical attention right away. Typically, you’ll need to pause taking Elrexfio (elranatamab) while your oncologist looks into it. Depending on how serious the side effect is, you might be able to restart Elrexfio (elranatamab). Or, you might have to stop taking it altogether.
Because these side effects can affect your thinking and movement, you’re recommend to avoid driving or doing activities that need a lot of focus and attention for at least 2 days after your step-up doses of Elrexfio (elranatamab), or anytime you start to experience symptoms.
Because Elrexfio (elranatamab) can cause serious side effects such as cytokine release syndrome (CRS) and nervous system problems including immune effector-cell associated neurotoxicity syndrome (ICANS), it is only available through a special program called a Risk Evaluation and Mitigation Strategy (REMS). This program requires your oncologist and pharmacy to complete special training to prescribe and dispense Elrexfio (elranatamab). Your oncologist must know how to diagnose and treat these serious side effects, and must discuss these side effects with you before you start taking Elrexfio (elranatamab).
People who take Elrexfio (elranatamab) commonly develop infections. Sometimes, the infections can be serious, such as pneumonia and sepsis. You’re at risk for infections because your immune system might not work as well when you have multiple myeloma. Additionally, the treatment you take for multiple myeloma, such as Elrexfio (elranatamab), can weaken your immune system even more because they lower your white blood cell (WBC) count. As a result, your body can’t fight infections as well.
Your oncology team might recommend you take certain medications, such as antivirals or antibiotics, to help prevent infections. They will also order blood tests to check your WBC level before you start Elrexfio (elranatamab) and regularly throughout treatment to make sure it’s within a safe range. You can lower your risk of getting sick by washing your hands often and avoiding crowds. Check your temperature regularly, and call your provider right away if your temperature is 100.4 degrees Fahrenheit or higher. Contact your care team right away if you have any signs or symptoms of infection such as fever, body aches, chills, or cough.
Sometimes, people taking Elrexfio (elranatamab) had high liver enzymes, which is a sign of liver irritation. Your oncologist will monitor your liver health using blood tests, because usually you won’t notice any symptoms or feel differently. But, if you do have yellowish skin, yellow eyes, or sudden stomach pain, contact your oncology team right away. If your lab tests are abnormal, you might need to pause taking Elrexfio (elranatamab) while your oncologist looks into it.
Based on the way Elrexfio (elranatamab) works, it might harm an unborn baby or raise the risk for miscarriage (pregnancy loss) when taken during pregnancy. Because of these risks, if you’re a female who can get pregnant, you should use birth control while taking Elrexfio (elranatamab) and for 4 months after the last dose. Your oncologist ask you to take a pregnancy test before you start Elrexfio (elranatamab) to make sure you’re not pregnant. Let your oncology team know right away if you become pregnant while taking Elrexfio (elranatamab).
Elrexfio (elranatamab) is injected under the skin by a trained healthcare professional on your oncology team, typically in a hospital or clinic setting.
Starting dose (“step-up” dosing): During your first week of treatment, your oncologist will raise your dose over the course of a week.
Day 1 dose: 12 mg injected once.
Day 4 dose: 32 mg injected once.
Day 8 dose: 76 mg injected once.
Maintenance dose: Starting a week after the last dose, your oncologist will inject 76 mg under the skin once a week.
If the medication works well for you for at least 6 months, your oncologist might lower your dose to 76 mg once every two weeks.
Your oncologist will also prescribe several medications before the first three doses to help prevent a serious side effect called cytokine release syndrome. These include dexamethasone and diphenhydramine (Benadryl).
Advanced multiple myeloma in adults who've already tried at least four other therapies
Advanced multiple myeloma in adults who've already tried at least four other therapies
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