Antibody-Drug Conjugates: Which Cancers They Treat

An antibody-drug conjugate has three parts, and FDA labels name them in a consistent way.

One part is an antibody that knows one specific protein. One part is a strong drug. A chemical linker holds the two together.

The label name reflects that. Enhertu is called a HER2-directed antibody and topoisomerase inhibitor conjugate. Padcev is a Nectin-4-directed antibody and microtubule inhibitor conjugate. That phrase tells you two things. It gives the target and the kind of drug being carried.

The antibody locks onto its target. The whole package is then pulled into the cell. The drug is released inside. The aim is to focus the drug at the cancer. Regular chemotherapy spreads it evenly through the body instead. ADCs still reach healthy cells. They carry serious side effects. They are more targeted, not risk-free.

Two ADCs cover most breast cancer use, and they target different proteins.

Enhertu targets HER2. Its label covers early disease and spread disease. For early disease, it is approved before surgery. That use is for HER2-positive stage II or III breast cancer. HER2-positive here means IHC 3+ or ISH positive, on an FDA-authorized test. It is then followed by a taxane, trastuzumab, and pertuzumab. It is also approved after surgery. That use applies when invasive disease remains after trastuzumab and taxane. For metastatic HER2-positive disease, it is approved with pertuzumab in the first line. It is approved on its own in later lines.

Trodelvy targets Trop-2. It carries a topoisomerase inhibitor. It is approved in triple-negative breast cancer that is locally advanced or metastatic. As a single drug, it is a first-line option. That applies to patients who cannot take PD-1 or PD-L1 inhibitor therapy. It is also a first-line option with pembrolizumab. That requires PD-L1 at a combined positive score of 10 or higher, on an FDA-authorized test. It is approved after two or more prior systemic therapies too. At least one of those must have been for metastatic disease.

Kadcyla, ado-trastuzumab emtansine, is another HER2-directed conjugate used in breast cancer.

Padcev targets Nectin-4. Its indications have grown in a specific direction worth noting: it now reaches earlier disease.

With pembrolizumab, it is approved around surgery. It is given before cystectomy and continued after. That use is for muscle-invasive bladder cancer. With pembrolizumab it is also approved for locally advanced or metastatic urothelial cancer.

As a single drug, it covers locally advanced or metastatic urothelial cancer in two spots. One is after a PD-1 or PD-L1 inhibitor and platinum chemotherapy. The other is in patients who cannot take cisplatin and have had one or more prior lines.

Our page on bladder cancer treatment by stage covers where this fits in the wider sequence.

Elahere targets folate receptor alpha. It is approved for adults whose tumor is positive for it. The disease must be platinum-resistant. It may be epithelial ovarian, fallopian tube, or primary peritoneal cancer. And the patient must have had one to three prior systemic regimens.

The label is explicit here. Patients are picked using an FDA-approved test. Without a positive result, the drug does not apply.

Tivdak targets tissue factor. It is approved for adults with recurrent or metastatic cervical cancer whose disease has progressed on or after chemotherapy.

The dose is worked out from body weight, up to a set ceiling, and your team calculates it. It goes in by vein over about 30 minutes, every 3 weeks. It runs until the disease grows or side effects become too much.

Adcetris targets CD30. Its label covers several settings in classical Hodgkin lymphoma. One is untreated stage III or IV disease in adults, with doxorubicin, vinblastine, and dacarbazine. One is untreated high-risk disease in children aged 2 and older, in a different combination. One is consolidation after an autologous stem cell transplant, for adults at high risk of relapse. And one is treatment after transplant failure. That last one also covers adults who are not transplant candidates and have had at least two prior multi-drug regimens.

Polivy targets CD79b. One approval pairs it with rituximab, cyclophosphamide, doxorubicin, and prednisone. That covers untreated diffuse large B-cell lymphoma or high-grade B-cell lymphoma. It applies to adults with an International Prognostic Index score of 2 or higher. A second approval pairs it with bendamustine and rituximab. That covers relapsed or refractory DLBCL after at least two prior therapies.

Blenrep targets BCMA, short for B-cell maturation antigen. Its current label is a combination. It is used with bortezomib and dexamethasone. That covers adults with relapsed or refractory multiple myeloma. They must have had at least two prior lines of therapy. Those lines must include a proteasome inhibitor and an immunomodulatory agent.

The dose is based on body weight and given by vein over about 30 minutes. It is given once every 3 weeks for 8 cycles, then continues every 3 weeks.

Note what changed here. The current approval is a combination approval. It carries specific prior-therapy rules. Any page calling this a single-drug myeloma treatment is describing an earlier situation.

Mylotarg targets CD33. One approval covers newly diagnosed CD33-positive acute myeloid leukemia. That applies to adults and children aged 1 month and older. A second covers relapsed or refractory CD33-positive AML, in adults and children aged 2 years and older.

Besponsa targets CD22. It is approved for relapsed or refractory CD22-positive B-cell precursor acute lymphoblastic leukemia. That covers adults and children aged 1 year and older.

Both pediatric age floors are on the label, which matters for families asking whether a drug applies to a child.

Every ADC above is named for a protein. That is not marketing shorthand. It is the rule that decides who can get it.

Several labels go further and demand a specific test. Enhertu requires HER2 status by an FDA-authorized test. Elahere requires a positive folate receptor alpha result by an FDA-approved test. Trodelvy's first-line combination requires PD-L1 at a combined positive score of at least 10. That also uses an FDA-authorized test.

So the real question is not just whether an ADC exists for a cancer. It is whether the tumor was tested for that target. And what the result said. Our page on biomarker testing covers how that testing works.

Indications in this class move quickly, and they move in both directions.

Padcev started in previously treated metastatic urothelial cancer. It now appears in muscle-invasive disease around surgery. Enhertu started in later-line metastatic breast cancer. It now appears before surgery in stage II and III disease. Blenrep's current label is a combination regimen with set prior-therapy rules.

One move stays reliable. Check the current FDA prescribing information for the drug itself. Or ask the oncology team which ADCs match this tumor's tested targets today.

ADCs carry a real drug, so a few problems need speed rather than a note for the next visit.

• Call 911 or go to an emergency department if you have a new cough, new breathlessness, or a fever that comes with either. Lung inflammation is a labeled risk of some of these drugs, and it can worsen fast. Get the same help for swelling of the face or throat, wheeze, or a rash with faintness during or soon after an infusion.
• Phone your oncology team immediately, at any hour, if your temperature reaches 100.4°F (38°C) or higher. CDC treats fever during this kind of treatment as an emergency, because these drugs can drop the white cells that fight infection. Take the drug name with you. If you cannot get through fast, go to an emergency department and tell them you are on this drug.
• Call your care team the same day if your eyes blur, dry out, or hurt, if your skin or eyes turn yellow, if your belly swells or you gain weight quickly, or if you have mouth sores or diarrhea you cannot control.
• Call your care team within a day or two if your hands or feet feel numb, tingly, or weak, or if bruising and small red skin spots appear.

Ask which of these fits the exact ADC you are on. The risks differ from drug to drug, and your team can tell you which one to watch for.

• DailyMed, ENHERTU label, accessed August 6, 2026.
• DailyMed, PADCEV label, accessed August 6, 2026.
• DailyMed, TRODELVY label, accessed August 6, 2026.
• DailyMed, ELAHERE label, accessed August 6, 2026.
• DailyMed, TIVDAK label, accessed August 6, 2026.
• DailyMed, ADCETRIS label, accessed August 6, 2026.
• DailyMed, POLIVY label, accessed August 6, 2026.
• DailyMed, BLENREP label, accessed August 6, 2026.
• DailyMed, MYLOTARG label, accessed August 6, 2026.
• DailyMed, BESPONSA label, accessed August 6, 2026.
• CDC, Watch Out for Fever — Preventing Infections in Cancer Patients, accessed August 13, 2026.