Instructions for Imdelltra (Tarlatamab-dlle)

1. Name:Imdelltra, Tarlatamab-dlle

2. Indications:

Imdelltra (Tarlatamab-dlle) is indicated for the treatment of adult patients with extensive-stage small cell lung cancer (ES-SCLC) whose disease has progressed during or after platinum-based chemotherapy.

3. Usage and dosage:

1. Medication Instructions: Before administering Imdelltra , ensure that the patient is adequately hydrated and as clinically indicated. Assess complete blood count, liver enzymes, and bilirubin before each administration. Administer according to an ascending dose schedule to reduce the incidence and severity of cytokine release syndrome (CRS); use recommended co-medications before and after the Cycle 1 infusion of Imdelltra to reduce the risk ofCRS reactions. Imdelltra should only be used by a medical professional with appropriate medical support to control serious reactions such as CRS and neurotoxicity, including immune effector cell-associated neurotoxic syndrome (ICANS), and patients should be monitored for 22 to 24 hours on Cycle 1 Day 1 and Cycle 1 Day 8; within 1 hour of starting the infusion and in an appropriate healthcare setting for a total of 48 hours.

2. Medication dosage: Imdelltra treatment plan is usually a 28-day (4-week) long cycle, adopting the recommended increasing dose plan, and using recommended combined medications. Give Imdelltra intravenously over one hour to reduce the incidence and severity of CRS.

(1) incremental plan:

1) Receive a smaller dose of Imdelltra, 1 mg, on Day 1 of the first treatment cycle (Cycle 1); receive the full treatment dose, 10 mg, on Days 8 and 15. On days 1 and 8, intravenously inject 8 mg of dexamethasone (or equivalent) within 1 hour before treatment with Imdelltra; on days 1, 8, and 15, inject 1 liter of normal saline intravenously within 4-5 hours immediately after completion of Imdelltrainfusion.

2) Receive the full treatment dose, i.e. 10mg, on day 1 and day 15 of the second treatment cycle (cycle 2);

3) Receive the full treatment dose, i.e. 10 mg, on day 1 and day 15 of the third and fourth treatment cycles (cycle 3);

4) Receive the full therapeutic dose, i.e. 10 mg, on days 1 and 15 of the fifth cycle and subsequent infusions;

(2) Imdelltra is administered every two weeks following an escalating dose regimen until disease progression or unacceptable toxicity.

3. Dosage adjustment: It is not recommended to reduce the dose of Imdelltra, but if adverse reactions occur after using the drug, it should be adjusted under the guidance of a doctor. Imdelltra treatment may be temporarily stopped or completely stopped if CRS, neurological problems, or any other serious side effects occur.

4. Adverse reactions:

In clinical studies of Imdelltra, the most common (>20%) adverse reactions were cytokine release syndrome, fatigue, pyrexia, dysgeusia, decreased appetite, musculoskeletal pain, constipation, anemia, and nausea; the most common (≥2%) Grade 3 or 4 laboratory abnormalities were lymphopenia, decreased sodium, increased uric acid, decreased total neutrophil count, decreased hemoglobin, increased activated partial thromboplastin time, decreased potassium, increased aspartate aminotransferase (AST), leukopenia, thrombocytopenia, and increased alanine aminotransferase (ALT).

5. Supply and storage:

InjectionImdelltra is a sterile, preservative-free white to slightly yellow lyophilized powder, available in 2mg, 10mg and other specifications. Refrigerate Imdelltra and IV Solution Stabilizer (IVSS) vials in their original cartons at 2°C to 8°C (36°F to 46°F), protected from light, until use. Do not freeze. Also store in original carton at room temperature 20°C to 25°C (68°F to 77°F) for up to 24 hours, protected from light.

6. Special groups:

1. Women: According to its mechanism of action, Imdelltra taken by pregnant women may cause harm to the fetus, causing T cell activation and cytokine release, and immune activation may impair pregnancy maintenance. Therefore, it is recommended that women of childbearing potential use effective contraceptive measures during drug treatment and for 2 months after the last dose; lactating women should not breastfeed for 2 months.

7. Mechanism of action:

Tarlatamab-dlle, the component of Imdelltra, is a bispecific T cell binder that binds DLL3 expressed on the surface of cells (including tumor cells) and CD3 expressed on the surface of T cells. Tarlatamab causes T cell activation, inflammatory cytokine release, and lysis of DLL3-expressing cells. Tarlatamab has antitumor activity in mouse models of small cell lung cancer.