Are there antibody-drug conjugates approved for Triple-Negative Breast Cancer

Antibody-Drug Conjugates for Triple-Negative Breast Cancer

Yes, there are antibody-drug conjugates (ADCs) approved for triple-negative breast cancer (TNBC), though the options differ depending on whether your cancer is early-stage or metastatic (spread to other parts of the body).

What Are Antibody-Drug Conjugates?

An ADC is a targeted therapy that works like a "guided missile." It's an antibody (a protein that recognizes cancer cells) attached to chemotherapy. The antibody finds and binds to a specific protein on cancer cell surfaces, then delivers the chemotherapy directly into the cell, where it's released to kill the cancer. This approach aims to maximize cancer-fighting power while minimizing damage to healthy cells.

FDA-Approved ADCs for TNBC

According to NCCN Guidelines for Metastatic Breast Cancer, the following ADCs are approved options:

Sacituzumab Govitecan (Trodelvy)

• Target: Trop-2 protein (found on TNBC cells)
• When used: Second-line or later treatment for metastatic TNBC
• How it works: Attaches to Trop-2, then releases chemotherapy inside the cancer cell
• NCCN Category: Category 1 (Preferred) for certain treatment lines

Fam-trastuzumab Deruxtecan (Enhertu, T-DXd)

• Target: HER2 protein
• Important note: While HER2-negative is part of TNBC's definition, some TNBC tumors have low levels of HER2 expression that may respond to this therapy
• When used: Can be considered in select metastatic TNBC cases
• NCCN Category: Other recommended regimen

Important Safety Consideration

Fam-trastuzumab deruxtecan is associated with interstitial lung disease (ILD) and pneumonitis — serious lung conditions. According to NCCN Guidelines, regular monitoring for this side effect is essential during treatment.

Questions to Ask Your Oncologist

1. Is my TNBC metastatic or early-stage? (This determines which ADCs are appropriate)
2. Has my tumor been tested for HER2 expression levels? (Even low levels might open up additional options)
3. Which ADC would you recommend for my specific situation, and why?
4. What are the side effects I should watch for, and how will you monitor me?
5. Are there clinical trials testing newer ADCs that I might be eligible for?

The Bigger Picture

TNBC has historically been challenging to treat because it lacks the hormone receptors (HR) and HER2 protein that other breast cancers have, limiting targeted therapy options. ADCs represent an important advance because they target different proteins (like Trop-2) that are often present on TNBC cells, expanding treatment possibilities beyond traditional chemotherapy.

Your oncologist will determine which ADC—if any—is most appropriate based on your specific tumor characteristics, prior treatments, and overall health.

---

This information is for educational purposes only. Always consult your healthcare team for personalized medical advice and decisions.