Who is this trial for?
This trial was for adults with newly diagnosed EGFR-mutated advanced non-small-cell lung cancer who had not yet been treated for their advanced disease.
People in the trial had:
- Non-small-cell lung cancer (NSCLC) with a specific EGFR mutation — either an “exon 19 deletion” or an “L858R” mutation, the two most common EGFR mutations that respond to targeted pills.
- Advanced or metastatic disease (the cancer had spread) that had not yet been treated with any therapy for the advanced setting.
- Brain metastases were allowed if stable — and about 4 in 10 patients had cancer that had spread to the brain, an important and common problem in this disease.
What kind of trial is this?
This trial tested whether combining two kinds of treatment — a targeted pill plus chemotherapy — could control the cancer for longer than the targeted pill alone in first-line treatment.
Background: why researchers asked this question
For lung cancer driven by an EGFR mutation, the targeted pill osimertinib transformed treatment: taken once a day, it controls the cancer well, is generally well tolerated, and reaches the brain. It became the standard first-line treatment based on an earlier trial (FLAURA).
But osimertinib is not a cure. In almost everyone, the cancer eventually finds a way around the pill and starts growing again — on average after about a year and a half. Chemotherapy attacks cancer cells in a completely different way, so researchers reasoned that giving chemotherapy alongside osimertinib from the start — hitting the cancer two ways at once — might keep it controlled for longer and delay the day it becomes resistant.
FLAURA2 was designed to test exactly that: osimertinib plus chemotherapy versus osimertinib alone, as the very first treatment for EGFR-mutated advanced lung cancer.
The trial: what was tested and how
FLAURA2 enrolled 557 people with previously untreated, EGFR-mutated advanced non-small-cell lung cancer across many countries. They were randomly assigned 1:1 to one of two first-line treatments:
- Osimertinib + chemotherapy (279 patients): the daily osimertinib pill plus chemotherapy (pemetrexed with cisplatin or carboplatin) for four cycles, then osimertinib with pemetrexed maintenance.
- Osimertinib alone (278 patients): the standard daily osimertinib pill on its own.
The trial was open-label (everyone knew which treatment they were getting). The main measure was progression-free survival — how long before the cancer grew or the person died. Overall survival — how long people lived — was a key secondary measure reported later, with longer follow-up.
A note before the results
Sue-Anne is a 60-year-old non-smoker who came to the emergency room with a new seizure. An MRI showed a brain tumor, and further scans found a lesion in her lung and tumors in her bones. A biopsy of the lung confirmed lung cancer with a common EGFR mutation that had already spread to her brain and bones.
When I met her, she had only just learned she had lung cancer. She was scared — not surprisingly — because she knew it was incurable, and she was also frightened of chemotherapy. I spent a long time explaining that a single pill, osimertinib, would be enough to control her disease. She could live a normal life on it for about two years, on average, before the cancer grew again. During that time I might see her every three months for scans; she might get some nail changes and a rash, but she would feel pretty much normal and well.
This trial has changed that conversation — because now I might try to convince her to take chemotherapy as well.
Results: what they found
Adding chemotherapy to osimertinib kept the cancer controlled longer and, with longer follow-up, helped people live longer — while adding the side effects that come with chemotherapy.
Osimertinib + chemotherapy vs osimertinib alone
The cancer stayed controlled about 9 months longer on average with the combination — a 38% lower risk of the cancer growing or of death at any given time (HR 0.62).
With longer follow-up, people on the combination lived nearly 10 months longer on average — a significant survival benefit (HR 0.77, P=0.02).
Most tumors shrank in both groups. Among those that responded, the response lasted longer with the combination — a median of 24.0 vs 15.3 months.
Serious side effects were about twice as common with the combination — driven by the added chemotherapy (low blood counts, nausea, fatigue). Most were manageable and reversible, but more people needed dose changes.
The benefit was seen across groups, but appeared especially large in people whose cancer had spread to the brain: among them, the combination delayed growth by a median of 24.9 months versus 13.8 months with osimertinib alone (HR 0.47). This matters because brain metastases are common and serious in EGFR-mutated lung cancer.
Why add chemotherapy to a targeted pill that already works well?
Osimertinib is effective, but cancers are made up of many slightly different cells, and over time some find a way to keep growing despite the pill — that is “resistance.” Chemotherapy kills cancer cells in a completely different way (by damaging them as they divide), so it can hit cells that the targeted pill alone might miss. Giving both together from the start aims to knock the cancer down harder and delay resistance — which is what FLAURA2 showed, with longer cancer control and longer survival.
Does everyone with EGFR-mutated lung cancer need the chemotherapy added?
Not necessarily — this is a genuine choice to discuss with your oncologist. Osimertinib on its own is simpler, gentler, and still very effective. Adding chemotherapy improves the odds but adds side effects and clinic visits for infusions. Some people — for instance those with a lot of disease, or with brain metastases — may have the most to gain from the combination, while others may reasonably prefer the pill alone. The “right” answer depends on the individual.
The bottom line
For newly diagnosed EGFR-mutated advanced lung cancer, adding chemotherapy to the targeted pill osimertinib kept the cancer controlled about 9 months longer (25.5 vs 16.7 months) and helped people live nearly 10 months longer (47.5 vs 37.6 months) than osimertinib alone. The benefit looked especially large in people with brain metastases. The cost is more side effects — serious ones were about twice as common — from the added chemotherapy. This makes osimertinib-plus-chemotherapy an important first-line option, alongside osimertinib alone.
What this could mean for you
- EGFR testing comes first. This treatment is only for lung cancers with an EGFR mutation (exon 19 deletion or L858R). Ask your team whether your tumor has been tested.
- There is a real choice here. Osimertinib alone is simpler and gentler; adding chemotherapy works better but is harder to tolerate. Both are reasonable — it is worth an honest conversation about the trade-off.
- Brain metastases may tip the balance. The combination’s benefit looked largest in people whose cancer had reached the brain.
- The side effects are mostly chemotherapy’s. Lower blood counts, nausea, and fatigue were more common with the combination, but were generally manageable and reversible.
- It improves survival, not just control. The combination didn’t only delay the cancer — people lived longer.
An oncologist’s perspective
After I explained the FLAURA2 results to Sue-Anne, she took a few days to mull over the chemotherapy and its added side effects, like tiredness and nausea. But she had just welcomed a new grandchild, and she felt that the chance of living at least a year longer was worth a few months of chemotherapy. That was over three years ago. Although the first three months of chemotherapy were tough, she got through them without any hospitalizations. She is still on osimertinib today, and since stopping the chemotherapy she has felt well enough to travel and babysit.
Questions & comments
Have a question about this trial? Ask below. Questions are read and answered by the site. We can’t give personal medical advice, but we’re glad to explain the research more clearly.