What is the package insert for gosatuzumab (Todavi) and how to use it correctly?

Gosatuzumab (Trodelvy) is an antibody-drug conjugate (ADC) whose active ingredient is gosatuzumab (Sacituzumab Govitecan-hziy). It is a drug targeting Trop-2 (tumor-associated antigen), which can selectively act on cancer cells expressing Trop-2 and kill cancer cells through its connected cytotoxic drug (SN-38, a topoisomerase I inhibitor). This drug is mainly used to treat certain types of breast cancer and urothelial cancer.

1. Indications

（1)Triple negative breast cancer (TNBC)

Gosatuzumab is indicated for the treatment of patients with metastatic triple-negative breast cancer (mTNBC) who have received two or more systemic therapies, including at least one advanced-stage therapy.

(2) Urothelial carcinoma (UC)

It is suitable for the treatment of patients with locally advanced or metastatic urothelial carcinoma who still have disease progression after receiving platinum-containing chemotherapy and PD-1/PD-L1 inhibitors.

2. Usage and dosage

Gosatuzumab is administered as an intravenous infusion (IV infusion ). Standard dosage and usage are as follows:

The recommended dose is 10 mg/kg by intravenous infusion twice a week (day 1 and day 8), and every 21 days constitutes a treatment cycle.

The first infusion should be administered no less than 3 hours to monitor for possible infusion-related reactions. If well tolerated, subsequent infusions may be shortened to 1 to 2 hours.

Treatment should be continued until the patient progresses or develops intolerable toxicity.

Medication adjustments for special populations:

Hepatic Impairment: This drug is not recommended for patients with severe hepatic impairment.

Renal Impairment: This drug can be used in patients with mild to moderate renal impairment, but should be used with caution in patients with severe renal impairment.

3. Side effects and management

Gosatuzumab may cause the following common side effects, and patients should monitor themselves closely and take appropriate measures if necessary:

(1) Myelosuppression (neutropenia)

Manifestations: Decreased white blood cells and platelets, which may increase the risk of infection.

Management method:

Monitor blood routine, if neutrophil count < 1500/mm³, it may be necessary to pause or adjust the dose.

To prevent infection, if there is febrile neutropenia (FN), growth factors (G-CSF) can be considered.

(2) Gastrointestinal adverse reactions (diarrhea, nausea, vomiting)

Performance: May lead to dehydration and electrolyte imbalance.

Management method:

Mild diarrhea can be relieved through dietary adjustments; severe diarrhea can be treated with antidiarrheal drugs such as loperamide.

If the diarrhea is severe (≥3 grade), the medication needs to be suspended and intravenous rehydration treatment should be given.

(3) Infusion-related reactions

Performance: Chills, hypotension, fever and other symptoms may occur during the infusion process.

Management method:

Use antihistamines or antipyretic and analgesics (such as acetaminophen) prophylactically.

If the infusion reaction is severe, the infusion can be suspended and the infusion rate can be continued to be reduced after the symptoms are relieved.

(4) Skin and allergic reactions

Manifestations: Rashes, itching, and even severe hypersensitivity reactions may occur.

Management method:

Mild rashes can be relieved with antihistamines or topical steroid creams.

Severe allergic reactions (such as laryngeal edema, difficulty breathing) require immediate discontinuation of the drug and emergency medical treatment.

4. Notes

(1) Avoid pregnancy and breastfeeding

Gosatuzumab may cause serious harm to the fetus. Female patients of childbearing age should undergo a pregnancy test before treatment and take effective contraceptive measures during treatment and for at least 6 months after the last dose.

Breastfeeding women should avoid breastfeeding for at least 1 months after the last dose.

(2)Drug interactions

The metabolites of this drugSN-38are mainly metabolized by UGT1A1, so coadministration with potent UGT1A1 inhibitors (such as azacitidine) may increase toxicity.

Avoid combined use with other drugs that may cause bone marrow suppression (such as certain chemotherapy drugs) to reduce side effects.

(3) Liver and kidney function monitoring

Because gosatuzumab is metabolized by the liver and excreted in the bile, patients with abnormal liver function (such as patients with liver metastases) should use it with caution and have liver function monitored regularly.

5. Precautions for drug storage and use

Storage Conditions: Unopened gosatuzumab should be stored between 2°C to 8°C (refrigerated) and avoid freezing or exposure to high temperatures.

Dilution and infusion: 0.9%sodium chloride or 5%glucose injection needs to be diluted before use, and after preparation 4Use within hours to ensure drug activity.

Disposal: This drug is a cytotoxic drug. The remaining liquid or containers after use should be properly disposed of in accordance with medical waste management regulations to avoid polluting the environment.

Gosatuzumab (Tordavir) is a highly effective Trop-2 targeting antibody - drug conjugate, mainly used to treat metastatic triple-negative breast cancer and urothelial carcinoma. Proper use includes intravenous infusion at recommended doses, close monitoring for side effects, and taking necessary management measures. Patients should be followed up regularly during the medication period to monitor hematological indicators, liver and kidney functions, and pay attention to infusion-related reactions.

In addition, patients should avoid pregnancy and breastfeeding, arrange their diet reasonably, and reduce discomfort caused by drugs. If serious side effects occur, you should seek medical attention immediately and adjust your medication regimen under the guidance of your doctor. By standardizing the use of gosatuzumab, the therapeutic effect can be maximized while reducing the impact of adverse reactions.

Reference materials:https://www.trodelvy.com/