Category/Class

Antibody drug conjugant (ADC)

Mechanism of Action

Sacituzumab govitecan-hziy is an ADC that consists of a humanized antibody that recognizes Trop-2 covalently attached to the topoisomerase I inhibitor SN-38. The ADC binds to Trop-2–expressing cancer cells, releasing the cytotoxic SN-38. SN-38 is a topoisomerase I inhibitor that breaks DNA strands, damages DNA, and causes apoptosis.

Indication

Treatment of adults with unresectable locally advanced or metastatic triple-negative breast cancer who have received two or more prior systemic therapies with at least one for metastatic disease, and treatment of adults with locally advanced or metastatic urothelial cancer who have received a platinum-containing chemotherapy and either a PD-1 or PD-L1 inhibitor

Dosing

10 mg/kg via IV once weekly on days 1 and 8 of a 21-day treatment cycle. Dose may be modified for adverse events based on toxicity grade and occurrence.

Administration

Give sacituzumab govitecan-hziy as an IV infusion over three hours. Slow or interrupt the infusion for reactions. Premedications are recommended to prevent reactions, including an antipyretic (e.g., acetaminophen) and histamine receptor antagonists (i.e., both H1 and H2 receptor antagonists). Patients who have experienced a previous infusion reaction should also receive a corticosteroid. Also administer primary prophylaxis for nausea or vomiting.

Observe the patient for signs or symptoms of infusion reactions during and for at least 30 minutes following the first dose. If the initial dose is well tolerated, subsequent infusions may be administered over one to two hours. Observe the patient during and for at least 30 minutes after the infusion.

Sacituzumab govitecan-hziy is a cytotoxic drug, and nurses should use safe handling and disposal precautions. Protect the infusion bag from light. Flush the IV line with 20 ml 0.9% sodium chloride after completing the infusion.

Adverse Reactions

More than 25% of patients experience neutropenia, nausea, diarrhea, fatigue, alopecia, anemia, vomiting, constipation, decreased appetite, rash, or abdominal pain.

Nursing Considerations

Patients are at increased risk for neutropenia, febrile neutropenia, and anemia if they are homozygous for the uridine diphosphate-glucuronosyl transferase 1A1 (UGT1A1)*28 allele. Ensure patients understand that sacituzumab govitecan-hziy may impair fertility and that it can cause fetal harm. Advise patients to use effective contraception. Give antiemetics prior to therapy, and ensure that patients have medications available for preventing and treating nausea and vomiting.

Patient Education

Provide information about potential adverse reactions and when and who to notify if symptoms occur. Review the signs and symptoms of an infusion reaction. Inform about prevention and management of nausea and vomiting, neutropenia, and diarrhea. Advise about the risk for embryo-fetal toxicity, to use effective contraception during treatment and for three months (males) or six months (females) after the last dose, and to avoid breastfeeding during and for at least one month after treatment. Advise that sacituzumab govitecan-hziy may impair fertility.

Gero-Oncology Considerations

No dosing adjustments are recommended in patients older than 65.

Safe Handling

Sacituzumab govitecan-hziy is considered a hazardous drug because of its reproductive risk for embryo-fetal toxicity. Use safe handling precautions.