Tagrisso is not a traditional chemotherapy drug. It is a targeted therapy, a newer class of cancer treatment that works differently from chemotherapy at a fundamental level. While both are used to treat cancer, the distinction matters because it affects how the drug is taken, how it attacks cancer cells, and what side effects you can expect.
How Tagrisso Differs From Chemotherapy
Traditional chemotherapy kills cells that multiply quickly, whether they’re cancerous or healthy. That’s why chemo causes widespread side effects like severe nausea, hair loss, and immune suppression: it can’t tell the difference between a fast-growing cancer cell and a fast-growing hair follicle or white blood cell.
Tagrisso takes a precision approach. Its generic name is osimertinib, and it belongs to a class called tyrosine kinase inhibitors (TKIs). It targets a specific protein on cancer cells called the epidermal growth factor receptor, or EGFR. When certain mutations cause this receptor to malfunction, it sends constant “grow and divide” signals to the cell. Tagrisso latches onto that receptor and blocks those signals. Because it’s designed to interfere with a specific molecular target rather than attack all rapidly dividing cells, it’s classified as a targeted therapy, sometimes also called precision medicine.
As a small molecule drug, Tagrisso can enter cancer cells directly and shut down the malfunctioning machinery inside. This is a different strategy from monoclonal antibodies, another type of targeted therapy that works from outside the cell surface.
What Tagrisso Treats
Tagrisso is approved for non-small cell lung cancer (NSCLC) that has specific EGFR mutations. Not all lung cancers have these mutations, so a tumor sample must be tested before the drug is prescribed. The FDA first granted regular approval in 2017 for patients with a mutation called T790M whose cancer had progressed on an older targeted therapy. It has since been approved as a first-line treatment for tumors with EGFR exon 19 deletions or exon 21 L858R mutations, meaning it can now be the first drug a patient receives after diagnosis.
How Effective Tagrisso Is
In the landmark FLAURA trial, which compared Tagrisso head-to-head against older EGFR-targeted drugs (erlotinib and gefitinib) as a first treatment for metastatic NSCLC, Tagrisso nearly doubled the time before the cancer progressed. Patients on Tagrisso had a median progression-free survival of 18.9 months compared to 10.2 months on the older drugs. Overall survival was also longer: 38.6 months versus 31.8 months.
How You Take It
One of the most practical differences between Tagrisso and chemotherapy is how it’s administered. Tagrisso is a pill you take at home, one 80 mg tablet once a day, with or without food. There are no infusion appointments, no IV lines, and no sitting in a treatment center for hours. If you have difficulty swallowing tablets, the pill can be dissolved in water. You continue taking it daily until the cancer progresses or the side effects become unmanageable.
Side Effects Compared to Chemo
Tagrisso’s side effect profile looks quite different from what most people associate with chemotherapy. The classic chemo experience of severe nausea, complete hair loss, and dangerously low blood counts is not typical with Tagrisso. Instead, the most common side effects include diarrhea, skin dryness or rash, nail changes, cough, and fatigue. Some patients experience back pain or a decreased sense of taste.
That said, Tagrisso is not without serious risks. Heart-related side effects are a real concern: some patients develop heart rhythm changes, chest pain, or shortness of breath. The drug can also cause lung inflammation (a condition called interstitial lung disease), which is uncommon but potentially dangerous. Blood clots in the legs or lungs are another possible complication. Vision changes, though less common, have also been reported.
The overall side effect burden tends to be more manageable than traditional chemotherapy for most patients, but “targeted” does not mean “mild.” Regular monitoring is part of the treatment plan.
When Tagrisso Is Combined With Chemotherapy
Here’s where the line blurs: in February 2024, the FDA approved Tagrisso in combination with platinum-based chemotherapy for certain patients. This approval was based on the FLAURA 2 trial, which enrolled 557 patients with EGFR-mutated advanced NSCLC who hadn’t received prior treatment. Patients who received Tagrisso plus chemotherapy had a median progression-free survival of 25.5 months, compared to 16.7 months for Tagrisso alone.
So while Tagrisso itself is not chemotherapy, your oncologist may prescribe it alongside chemotherapy to get a stronger response. In this scenario, you would experience side effects from both the targeted therapy and the chemo drugs. The combination is specifically for patients whose tumors carry exon 19 deletions or exon 21 L858R mutations, and the decision to add chemotherapy depends on the specifics of your cancer and overall health.
If you’ve been told you’ll receive Tagrisso, knowing that it’s a targeted therapy rather than chemotherapy gives you a clearer picture of what daily treatment looks like. For many patients, that means taking a pill each morning rather than scheduling regular infusions, with a different set of side effects to watch for.