Lesson 3
The seven approved drugs
Established science. Settled medical knowledge, curated for teaching — distinct from the platform’s own evolving research.
These are the HER2-targeted medicines approved for patients, from the first one in 1998 to the newest. Each carries two names — a brand name and a generic name — and each works in one of the three ways from Lesson 2. They’re grouped here by how they work.
Antibodies — block it from outside
Acts on the outside of the cell
Large molecules that clamp onto the outer part of HER2 and stop it from pairing up and signalling.
Herceptin
Trastuzumab
First-line therapy for HER2+ breast cancer. Gold standard monoclonal antibody.
In technical terms: Monoclonal antibody that binds to the extracellular domain IV of HER2, inhibiting receptor dimerization and triggering antibody-dependent cellular cytotoxicity (ADCC)
Perjeta
Pertuzumab
Used in combination with trastuzumab for dual HER2 blockade.
In technical terms: Monoclonal antibody that binds to HER2 extracellular domain II, preventing HER2/HER3 heterodimerization
Kinase blockers — jam the switch inside
Acts on the inside of the cell
Small-molecule pills that slip inside the cell and plug the fuel pocket of HER2’s inner switch.
Tykerb
Lapatinib
Small molecule TKI for advanced HER2+ breast cancer.
In technical terms: Reversible dual EGFR/HER2 tyrosine kinase inhibitor that binds the ATP-binding pocket in the inactive kinase conformation
Nerlynx
Neratinib
Extended adjuvant therapy for early-stage HER2+ breast cancer.
In technical terms: Irreversible pan-HER tyrosine kinase inhibitor; covalently binds Cys805 in the ATP-binding pocket
Tukysa
Tucatinib
For metastatic HER2+ breast cancer, including brain metastases.
In technical terms: Highly selective HER2 tyrosine kinase inhibitor with minimal EGFR inhibition, reducing skin and GI toxicity
Guided missiles — deliver chemo to the target
Homes in from outside, acts inside
An antibody tied to a chemotherapy payload — it finds HER2-positive cells and releases the drug inside them.
Kadcyla
Ado-trastuzumab emtansine
Second-line ADC for HER2+ metastatic breast cancer.
In technical terms: Antibody-drug conjugate: trastuzumab linked to cytotoxic agent DM1 (emtansine). Delivers chemotherapy directly to HER2-overexpressing cells after receptor-mediated internalization
Enhertu
Trastuzumab deruxtecan
Breakthrough therapy for HER2+ and HER2-low metastatic breast cancer.
In technical terms: Next-gen ADC with cleavable linker and topoisomerase I inhibitor payload. Higher drug-to-antibody ratio (8:1) with bystander killing effect
That’s the full set of approved HER2 medicines — and you can now see the pattern behind all of them. A cancer that leans on HER2 gives doctors a clear target, and these seven drugs hit it three different ways.
Beyond the settled science: the platform’s frontier
Approved drugs are the settled end of the story. The open end — why some cancers develop resistance, which mutations blunt which drug, and what the next generation of treatments might target — is where this platform does its work, reading the newest research as it appears. That frontier is kept separate from this guide so the settled science stays clearly settled.
This guide is for education only and is not medical advice. Approval years and uses vary by country and change over time.