Tarlatamab-dlle (Imdelltra™)

Author: Marisa Healy, BSN, RN
Content Contributor: Sophia Gilardone, PharmD, BCOP and Kristyn Krajewski, PharmD
Last Reviewed: June 06, 2024

Pronounce: tar-LAT-ue-mab

Classification: Bispecific T-cell Engager

About Tarlatamab-dlle (Imdelltra™)

Tarlatamab-dlle is a type of medication called a bispecific T-cell engager (BiTE) antibody. This medication helps your body’s T-cells (part of your immune system) target and kill cells that have a certain protein on their surface. Tarlatamab-dlle targets the delta-like ligand 3 (DLL3) protein. DLL3 is found on the surface of cancer cells in certain types of lung cancer.

How to Take Tarlatamab-dlle (Imdelltra™)

Tarlatamab-dlle is given by intravenous (IV, into a vein) infusion. The first time you receive this medication, you will receive a smaller dose for the first day. The next doses will be the normal dose if you tolerate the medication. This is called “step-up dosing.” You will receive the first two doses in a hospital. A third dose will be given 7 days later in an outpatient facility, after which you will receive your treatment dose outpatient every two weeks.  

For the first 2 doses, your care team will monitor you in the hospital for 22 to 24 hours after the infusion. Following the first two infusions, it is recommended that you and a caregiver stay within 1-hour of an appropriate healthcare setting for a total of 48 hours from the start of the infusion. As your treatment goes on, if tolerated, the length of monitoring time will go down.

You will be given “pre-medications” before each step-up dose of tarlatamab-dlle, including dexamethasone (a steroid). Some patients will need these pre-medications with every dose depending on how they tolerate taralatamab-dlle. 

Tell your care team about all the medications you take, including prescription and over-the-counter medications, vitamins, and herbal supplements. You should not drive or operate heavy machinery during treatment with this medication.

Possible Side Effects

There are a number of things you can do to manage the side effects of tarlatamab-dlle. Talk to your care team about these recommendations. They can help you decide what will work best for you. These are some of the most common or important side effects:

Cytokine Release Syndrome

Cytokine release syndrome (CRS) can happen. This medication activates T-cells, causing them to release many cytokines. The cytokines cause an inflammatory response in the body. This reaction, if left untreated, can be very dangerous. Signs and symptoms may be fever, having a hard time breathing, chills, low blood pressure, fast heart rate, headache, and higher levels of liver enzymes in your blood. Your care team will monitor you closely for CRS while you are receiving this medication. Callyour provider right away if you have any signs or symptoms of CRS so that treatment can be started.

Neurologic Toxicity including ICANS

This medication can cause neurologic (brain) toxicities and immune effector cell-associated neurotoxicity. Signs and symptoms may be confusion and feeling more tired than usual. Your care team will monitor you for any changes in your mental status. If you or a loved one notices any changes, call your care team right away.

Infection and Low White Blood Cell Count (Lymphopenia or Neutropenia)

This medication can cause life-threatening infections, with or without a decrease in white blood cell counts.

White blood cells (WBC) are important for fighting infection. While receiving treatment, your WBC count can drop, putting you at a higher risk of getting an infection. You should let your care team know right away if you have a fever (temperature greater than 100.4°F or 38°C), sore throat or cold, shortness of breath, cough, burning with urination, or a sore that doesn't heal.

Tips for preventing infection:

  • Washing hands, both yours and your visitors, is the best way to prevent the spread of infection.
  • Avoid large crowds and people who are sick (such as those who have a cold, fever, or cough, or live with someone with these symptoms).
  • When working in your yard, wear protective clothing including long pants and gloves.
  • Do not handle pet waste.
  • Keep all cuts or scratches clean.
  • Shower or bathe daily and perform frequent mouth care.
  • Do not cut cuticles or ingrown nails. You may wear nail polish, but not fake nails.
  • Ask your oncology care team before scheduling dental appointments or procedures.
  • Ask your oncology care team before you, or someone you live with, has any vaccinations.

Fatigue

Fatigue is very common during cancer treatment and is an overwhelming feeling of exhaustion that is not usually relieved by rest. It can cause physical, emotional, and mental exhaustion. While on cancer treatment, and for a period after, you may need to adjust your schedule to manage fatigue. Plan times to rest during the day and conserve energy for more important activities. Exercise can help combat fatigue; a simple daily walk with a friend can help. Talk to your care team for helpful tips on dealing with this side effect.

Decrease in Appetite and Taste Changes

Nutrition is an important part of your care. Cancer treatment can affect your appetite and, in some cases, the side effects of treatment can make eating difficult. This medication can cause a metallic taste in your mouth. Ask your oncology care team about nutritional counseling services at your treatment center to help with food choices.

  • Try to eat five or six small meals or snacks throughout the day, instead of 3 larger meals.
  • If you are not eating enough, nutritional supplements may help.
  • You may experience a metallic taste or find that food has no taste at all. You may dislike foods or beverages that you liked before receiving cancer treatment. These symptoms can last for several months or longer after treatment ends.
  • Avoid any food that you think smells or tastes bad. If red meat is a problem, eat chicken, turkey, eggs, dairy products, and fish without a strong smell. Sometimes cold food has less of an odor.
  • Add extra flavor to meat or fish by marinating it in sweet juices, sweet and sour sauce, or dressings. Use seasonings like basil, oregano, or rosemary to add flavor. Bacon, ham, and onion can add flavor to vegetables.

Low Red Blood Cell Count (Anemia)

Your red blood cells are responsible for carrying oxygen to the tissues in your body. When the red cell count is low, you may feel tired or weak. You should let your oncology care team know if you experience any shortness of breath, difficulty breathing or pain in your chest. If the count gets too low, you may receive a blood transfusion.

Electrolyte Abnormalities

This medication can affect the normal levels of electrolytes (sodium, potassium, magnesium, etc.) in your body. Your levels will be monitored using blood tests. If your levels become too low, your care team may prescribe specific electrolytes to be given by IV or taken by mouth. Do not take any supplements without first consulting with your care team. 

Liver Toxicity

This medication can cause liver toxicity, which your oncology care team may monitor for using blood tests called liver function tests. Tell your healthcare provider if you notice yellowing of the skin or eyes, your urine appears dark or brown, or you have pain in your abdomen (belly), as these can be signs of liver toxicity.

Low Platelet Count (Thrombocytopenia)

Platelets help your blood clot, so when the count is low you are at a higher risk of bleeding. Let your oncology care team know if you have any excess bruising or bleeding, including nose bleeds, bleeding gums or blood in your urine or stool. If the platelet count becomes too low, you may receive a transfusion of platelets.

  • Do not use a razor (an electric razor is fine).
  • Avoid contact sports and activities that can result in injury or bleeding.
  • Do not take aspirin (salicylic acid), non-steroidal, anti-inflammatory medications (NSAIDs) such as Motrin/Advil (ibuprofen), Aleve (naproxen), Celebrex (celecoxib) etc. as these can all increase the risk of bleeding. Please consult with your healthcare team regarding the use of these agents and all over-the-counter medications/supplements while on therapy.
  • Do not floss or use toothpicks and use a soft-bristle toothbrush to brush your teeth.

Muscle or Joint Pain/Aches

Your healthcare provider can recommend medications and other strategies to help relieve pain.

Constipation

There are several things you can do to prevent or relieve constipation. Include fiber in your diet (fruits and vegetables), drink 8-10 glasses of non-alcoholic fluids a day, and keep active. A stool softener once or twice a day may prevent constipation. If you do not have a bowel movement for 2-3 days, call your healthcare team for suggestions to relieve the constipation.

Kidney Problems

This medication can cause kidney problems, including an increased creatinine level, which your oncology care team may monitor for using blood tests. Tell your healthcare provider if you have decreased urine output, blood in your urine, swelling in your ankles, or loss of appetite.

Nausea and/or Vomiting

Talk to your oncology care team so they can prescribe medications to help you manage nausea and vomiting. In addition, dietary changes may help. Avoid things that may worsen the symptoms, such as heavy or greasy /fatty, spicy or acidic foods (lemons, tomatoes, oranges). Try saltines or ginger ale to lesson symptoms.

Call your oncology care team if you are unable to keep fluids down for more than 12 hours or if you feel lightheaded or dizzy at any time.

Less common, but important side effects can include:

  • Allergic Reactions: In some cases, patients can have an allergic reaction to this medication. Signs of a reaction can include: shortness of breath or having a hard time breathing, chest pain or tightness, wheezing, coughing, feeling lightheaded or dizzy, and a new rash. If you see or feel any changes during the infusion, let your nurse know right away. The infusion will be slowed or stopped if this happens.

Reproductive Concerns

Exposure of an unborn child to this medication could cause birth defects, so you should not become pregnant while on this medication. Effective birth control is necessary for women during treatment and for at least 2 months after treatment. Men should ask your provider about birth control needs. Even if your menstrual cycle stops or you believe you are not producing sperm, you could still be fertile and conceive. You should not breastfeed while receiving this medication or for 2 months after your last dose.