Imdelltra
Imdelltra (tarlatamab) is a medication used to treat advanced lung cancer that has spread, called extensive-stage small cell lung cancer (ES-SCLC). It’s approved for adults who have already been treated with platinum-based chemotherapy. This medication is a bispecific antibody, which helps your immune system find and attack cancer cells. It’s given by a healthcare professional as an intravenous (IV) infusion in a clinic or hospital. Common side effects include tiredness, fever, changes in taste, and a serious reaction called cytokine release syndrome (CRS).
What is Imdelltra (tarlatamab)?
What is Imdelltra (tarlatamab) used for?
- Extensive-stage small cell lung cancer (ES-SCLC) in adults whose cancer has worsened after platinum-based chemotherapy
How Imdelltra (tarlatamab) works
Imdelltra (tarlatamab) 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 DLL3, 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, Imdelltra (tarlatamab) brings T-cells close to the cancer cells, helping the immune system attack and destroy the cancer cells.
Drug facts
Side effects of Imdelltra (tarlatamab)
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.
Common Side Effects
- Lower white blood cells (84%)
- Blood electrolyte changes (up to 68%)
- Lower red blood cells (58%)
- Cytokine release syndrome (55%)
- Tiredness (51%)
- Higher liver enzymes (up to 44%)
- Fever (36%)
- Changes in taste (36%)
- Reduced appetite (34%)
- Lower platelets (33%)
- Constipation (30%)
- Muscle pain (30%)
- Higher creatinine level in blood (29%)
- Nausea (22%)
Less Common Side Effects
- Trouble breathing
- Cough
Imdelltra (tarlatamab) serious side effects
Contact your healthcare provider immediately if you experience any of the following.
- Cytokine release syndrome (CRS): Fever, trouble breathing, chills, dizziness, fast heartbeat, headache, feeling anxious
- Nervous system problems: headache, numbness, dizziness, confusion, sleepiness, trouble speaking or writing, shaking, muscle weakness, pain, seizures
- Serious infection: fever, body aches, chills, feeling very tired or weak, very fast heartbeat, cough, chest pain, shortness of breath, rash, sore throat
- Liver problems: pain in the right upper stomach yellowing of the skin or eyes, tiredness, loss of appetite, dark urine
- Severe allergic reactions: trouble breathing, wheezing, coughing, lightheaded, dizziness, rash
The following Imdelltra (tarlatamab) side effects have also been reported
Side effects that you should report to your care team as soon as possible:
- Allergic reactions—skin rash, itching, hives, swelling of the face, lips, tongue, or throat
- Fever, chills, unusual weakness or fatigue, loss of appetite, nausea, headache, dizziness, feeling faint or lightheaded, shortness of breath, fast or irregular heartbeat, which may be signs of cytokine release syndrome
- Infection—fever, chills, cough, sore throat, wounds that don't heal, pain or trouble when passing urine, general feeling of discomfort or being unwell
- Liver injury—right upper belly pain, loss of appetite, nausea, light-colored stool, dark yellow or brown urine, yellowing skin or eyes, unusual weakness or fatigue
- Low red blood cell level—unusual weakness or fatigue, dizziness, headache, trouble breathing
- Pain, tingling, or numbness in the hands or feet, muscle weakness, change in vision, confusion or trouble speaking, loss of balance or coordination, trouble walking, seizures
- Unusual bruising or bleeding
Side effects that usually do not require medical attention (report these to your care team if they continue or are bothersome):
- Bone pain
- Change in taste
- Constipation
- Loss of appetite
- Muscle pain
- Nausea
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Pros and cons of Imdelltra (tarlatamab)
Pros
- Works in a more specific, targeted way than traditional chemotherapy
- Recommended therapy for advanced small cell lung cancer
- Given every 2 weeks after initial doses
Cons
- Requires long observations times with the first few doses
- Commonly causes tiredness, fever, and changes in taste
- Raises your risk of infection
Pharmacist tips for Imdelltra (tarlatamab)
- Imdelltra (tarlatamab) can cause a serious immune reaction called cytokine release syndrome (CRS). Call your oncologist right away if you have fever, chills, fast or irregular heartbeat, trouble breathing, or dizziness.
- To help prevent CRS, your oncology care team will give you premedications like dexamethasone 1 hour before your first few doses of Imdelltra (tarlatamab). You’ll also get fluids right after each infusion.
- If you stop taking Imdelltra (tarlatamab) for a while, you might need to restart the step-up dosing schedule. This depends on how long the break was and when it happened.
- Each Imdelltra (tarlatamab) infusion takes about 1 hour. You'll also need to stay afterward for monitoring, so plan for a full day and bring something to help pass the time.
- You will be watched for several hours after your Imdelltra (tarlatamab) infusion, especially during the first few treatment cycles. If you don’t have serious side effects like CRS, this time can get shorter with later doses.
- For the first two doses of Imdelltra (tarlatamab), you must stay within 1 hour of a healthcare center for 48 hours. Make sure a caregiver is with you during this time in case you need help.
- A fever of 100.4°F or higher during Imdelltra (tarlatamab) treatment could mean you have CRS or an infection. Call your oncologist or get help right away if this happens.
- Always carry your Patient Wallet Card while taking Imdelltra (tarlatamab). This lets other healthcare professionals know about your medication in case of an emergency.
- Imdelltra (tarlatamab) can affect your brain and nerves. Tell your care team if you have a headache, feel dizzy or confused, or notice shaking. Don’t drive or use heavy machines until your symptoms are gone.
- Imdelltra (tarlatamab) commonly lowers your blood cell counts. This can make it harder for your body to fight off infections. Let your oncologist know right away if you have fever, chills, cough, or trouble breathing.
- It’s important to stay hydrated while taking Imdelltra (tarlatamab). You’ll get fluids through an IV on treatment days, but be sure to drink plenty of water between doses too.
- Imdelltra (tarlatamab) can harm an unborn baby. If you can become pregnant, use birth control during treatment and for 2 months after your last dose. Let your oncologist know right away if you become pregnant.
- Don’t breastfeed while taking Imdelltra (tarlatamab) and for 2 months after the last dose. It’s not known if this medication passes into breast milk, but it could be harmful to a nursing baby.
Common questions about Imdelltra (tarlatamab)
No. Imdelltra (tarlatamab) isn’t considered chemotherapy because it works differently. Chemotherapy attacks any cell that grows very quickly, while Imdelltra (tarlatamab) is an immunotherapy. It only binds to certain proteins on cancer and immune cells, helping your immune system specifically attack the cancer cells.
Yes. Imdelltra (tarlatamab) is FDA approved. It was first granted accelerated approval in May 2024 to treat extensive-stage small cell lung cancer, based on early evidence showing it could be helpful. Then in, November 2025, the FDA granted full approval, which means more data confirmed that the medication works well and is safe.
Sort of. The first two doses of Imdelltra (tarlatamab) require you to be watched for 22 to 24 hours, but that doesn’t always mean you’ll need to stay in a hospital. Some clinics or infusion centers are open 24 hours and might let you stay in a special area for monitoring where you can go home afterward. For later doses, shorter monitoring times mean you likely won’t need hospital care — unless you have a serious side effect like severe CRS or nervous system problems.
In studies, about 40% of people with extensive-stage small cell lung cancer (ES-SCLC) responded to Imdelltra (tarlatamab), meaning their tumors got smaller or stopped growing. Some people had a complete response, where the cancer could no longer be seen. Talk to your oncologist to see if this medication could be a good choice for you.
You’ll keep taking Imdelltra (tarlatamab), as long as it's working and you’re not having serious side effects. Your oncology care team will check your progress and how you're feeling to decide if you should keep going. If the cancer gets worse or side effects become too difficult, your oncologist might stop the medication.
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Risks and warnings for Imdelltra (tarlatamab)
Imdelltra (tarlatamab) 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
Imdelltra (tarlatamab) can cause a reaction called cytokine release syndrome (CRS). CRS happens when your immune system reacts too strongly to the medication. Symptoms can include headache, chills, fever, low blood pressure, trouble breathing, fast heartbeat, and confusion. Most cases are mild or moderate, but some can be more serious. CRS usually happens during the early “step up” doses, often starting a few hours after your infusion and lasting a few days.
To help lower your risk, your care team will follow a “step-up” dosing plan and give you other medications before your infusion and fluids afterward. You’ll get Imdelltra (tarlatamab) at a hospital or clinic where staff can watch you closely and treat CRS right away if it happens. Drink plenty of fluids, and let your care team know right away if you notice any CRS symptoms. If CRS does happen, your oncologist might stop the medication and give you treatment based on how severe your symptoms are.
Serious nervous system problems
Imdelltra (tarlatamab) can cause serious nervous system problems, including a condition called immune effector cell-associated neurotoxicity syndrome (ICANS). This can happen as early as the day after your treatment starts or even a few months later, but it usually starts about a month in. Tell your care team right away if you notice symptoms like a headache, numbness or tingling, dizziness, confusion, feeling very sleepy, or having trouble thinking clearly. If you feel different in how you think or stay alert, don’t drive or use heavy machines until you’re feeling normal again.
Lower blood cell count
Imdelltra (tarlatamab) commonly causes lower blood cell counts. Low white blood cells make it harder to fight infections 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 check your blood counts before each dose and as needed during treatment. If your blood cell levels drop too much, they might pause or stop the medication.
Infections
Sometimes, people taking Imdelltra (tarlatamab) developed serious infections such as COVID-19, urinary tract infection (UTI), pneumonia. It’s important to tell your oncologist right away if you have signs or symptoms of an infection such as fever, body aches, chills, cough, or low blood pressure.
Serious liver problems
Imdelltra (tarlatamab) can raise your liver enzymes, which might be a sign that your liver is irritated or not working properly. Your care team will do blood tests to check your liver before each dose and as needed during treatment. If your liver levels get too high, they might pause or stop your treatment based on how serious it is.Tell your oncologist if you notice signs of liver problems, like yellowing of your skin or eyes, dark urine, or pain in the upper right stomach.
Hypersensitivity reaction
Imdelltra (tarlatamab) can cause severe allergic reactions. Signs can include rash, trouble breathing, or tightness in your chest. Your care team will monitor you during treatment and manage any symptoms if they happen. Depending on how serious the reaction is, your oncologist might pause or permanently stop your treatment.
Harm to unborn baby
Based on the way Imdelltra (tarlatamab) 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 2 months after the last dose. Let your oncologist know if you’re pregnant or thinking about becoming pregnant while taking Imdelltra (tarlatamab).
Imdelltra (tarlatamab) dosage
Kit| Dosage | Quantity | Price as low as | Price per unit |
|---|---|---|---|
| 1mg | 1 kit | $1,489.45 | $1,489.45 |
| 10mg | 1 kit | $14,838.25 | $14,838.25 |
Typical dosage for Imdelltra (tarlatamab)
The recommended dose of Imdelltra (tarlatamab) follows a step-up schedule to help lower the risk of serious side effects. Once the step-up doses are complete, you’ll get an infusion every 2 weeks. Each treatment cycle lasts 28 days.
- Cycle 1
- Day 1: 1mg, Day 8: 10mg, Day 15: 10mg
- Cycle 2
- Day 1: 10mg, Day 15: 10mg
- Cycles 3 and 4
- Day 1: 10mg, Day 15: 10mg
- Cycle 5 and beyond
- Day 1: 10mg, Day 15: 10mg
How much does Imdelltra (tarlatamab) cost?
$1,489.45
What are alternatives to Imdelltra (tarlatamab)?
Imdelltra (tarlatamab) images
