Trodelvy (Sacituzumab): What to Expect

This drug has two halves joined together. That design is called an antibody-drug conjugate.

The first half is an antibody that finds Trop-2, a protein sitting on the surface of many breast cancer cells. The second half is SN-38, the active form of the chemotherapy drug irinotecan. A chemical link holds them together.

The antibody docks onto the cancer cell. The link breaks. The chemotherapy is released right there, instead of everywhere at once. Some of it also leaks to nearby cells, which is part of how it works and part of why side effects still happen.

Trodelvy is the brand name; sacituzumab govitecan is the generic name.

The FDA boxed warning names low white cells and diarrhea. Both are common enough that your team plans for them from the start.

Neutropenia, a drop in infection-fighting white cells, happened in 64% of people in the trials. It reached a severe grade in 48%. It can begin in the very first cycle. Blood is checked regularly, and a growth-factor injection called G-CSF is recommended in advance for anyone at higher risk.

Diarrhea occurred in 62% of people, and was severe in 10%.

That is not a side effect to manage by waiting. Ask three things before your first dose. Which anti-diarrhea medicine should I keep at home? At what point do I start taking it? And at what point do I call you instead?

The label's approach is to check first that an infection is not the cause, then start the anti-diarrhea plan your team gave you promptly — if you were not given one, that is a same-day call, not a reason to improvise from a pharmacy shelf. Dehydration is the real danger, and it has caused kidney injury. Keep drinking, and call if you cannot keep fluids down.

Your liver clears SN-38 using an enzyme made by the UGT1A1 gene. Some people inherit two copies of a slower version, known as UGT1A1*28.

In them the chemotherapy hangs around longer. Among people with two copies of that version, severe neutropenia occurred in 57%. Anemia is also more likely.

Testing for this is available. If you have had a bad reaction to irinotecan in the past, or a family member has, say so before you start.

Triple-negative breast cancer that is metastatic or cannot be removed by surgery. It is used first line on its own for people who are not candidates for a PD-1 or PD-L1 drug. It is used first line with pembrolizumab when the tumor's PD-L1 combined positive score is 10 or more. And it is used after two or more earlier treatments, at least one of them for spread disease.

Hormone-receptor-positive, HER2-negative breast cancer that is metastatic or unresectable, after hormone-based treatment and at least two more treatments for spread disease.

An earlier accelerated approval covered urothelial cancer, the cancer of the bladder and urinary tract. It was withdrawn in November 2024 and is no longer an approved use. If you find a page describing this drug for bladder cancer, it is out of date.

The dose is worked out from your weight and given into a vein on day 1 and day 8 of every 21-day cycle. So it is two visits, then a week with none.

You are given medicines beforehand to reduce infusion reactions and sickness. Staff watch you during the infusion and for at least half an hour afterwards.

One safety note belongs to the pharmacy as much as to you. This drug must never be swapped for, or given with, irinotecan.

• Call 911 or go to an emergency department if a rash, swelling, wheeze or dizziness comes on during an infusion or soon after it, or if you cannot stand up without the room spinning after a day of diarrhea.
• Call your cancer team the moment it happens, day or night, if your temperature hits 100.4°F (38°C) or higher, or you get chills and shivering. Low white cells start in the very first cycle with this drug, so a fever is a medical emergency and needs assessing within the hour. If you cannot reach the team quickly, go to an emergency department and tell them at once that you are on sacituzumab govitecan.
• Go to an emergency department the same day if diarrhea keeps going despite the loperamide plan you were given, you cannot keep fluids down, or you have stopped passing much urine. Severe diarrhea on this drug has caused kidney injury, and fluids into a vein may be needed. Ring your care team on the way.
• Call your care team within a day or two if stairs leave you breathless, or you look pale and feel worn out in a way that is new. Hair thinning, nausea and ordinary tiredness are rarely urgent, but tell your team anyway, because there is usually something that helps.

• https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=57a597d2-03f0-472e-b148-016d7169169d
• https://www.cancer.gov/about-cancer/treatment/drugs/sacituzumabgovitecan-hziy
• https://www.fda.gov/drugs/resources-information-approved-drugs/withdrawn-cancer-accelerated-approvals
• https://www.cdc.gov/cancer-preventing-infections/patients/fever.html