OnCo
trialsTrialMixed

TROPION-Breast01

The trial that got Datroway approved in hormone-positive breast cancer, though it did not extend overall survival.

PFS 6.9 vs 4.9 months (HR 0.63); OS not significantly different (HR 1.01). Approved January 2025 in the US on PFS.

Setting
HR+/HER2- metastatic breast cancer after endocrine and 1-2 chemotherapies: Dato-DXd vs chemotherapy
Phase
Phase 3
Sponsor
AstraZeneca / Daiichi Sankyo
Registry
Headline result
PFS HR 0.63; OS HR 1.01.
Reported
2023
Enrolled
732
Replication
PFS-only benefit; the OS result did not replicate the PFS signal. The HR+ population is also served by TROPiCS-02 (sacituzumab), which did show an OS benefit.

Outcomes

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In plain words
What these results mean for people, not percentages
732 people took part
Progression-free survival (BICR)primarysurrogate endpoint
  • Median 6.9 vs 4.9 months with Datopotamab deruxtecan compared with Chemotherapy (ICC); about 2 months longer for half the group.
  • A median is a midpoint: half the people did better than this and half did worse, so it is not a prediction for any one person.
  • Put another way, the treated group had about 37 percent lower chance of the event at any given time (hazard ratio 0.63, likely range 0.52 to 0.76).
  • This is a surrogate endpoint: it measures the cancer being controlled or absent on scans and tests, which often, but not always, translates into living longer.
Overall survivalprimarysurvival endpoint
  • Median 18.6 vs 18.3 months with Datopotamab deruxtecan compared with Chemotherapy (ICC); about 0.3 months longer for half the group.
  • A median is a midpoint: half the people did better than this and half did worse, so it is not a prediction for any one person.
  • Put another way, the treated group had about 1 percent higher chance of the event at any given time (hazard ratio 1.01, likely range 0.83 to 1.22).
  • The likely range for the hazard ratio crosses 1, so the difference could be due to chance.
  • Overall survival counts deaths from any cause, so it is the most direct measure of whether a treatment helps people live longer.
  • Not significant.
Objective response rateresponse endpoint
  • 36.4 vs 22.9 out of 100 had their tumour shrink with Datopotamab deruxtecan compared with Chemotherapy (ICC); 13.5 more per 100.
  • Roughly one extra person helped for every 7 treated. That is a rough figure taken from the two percentages, not a guarantee for any one person.
  • A response rate counts how many people had their tumours shrink by a set amount; shrinking is encouraging but does not by itself show that people live longer or feel better.
Be careful
  • These results apply to the people the trial enrolled: HR+/HER2- metastatic breast cancer after endocrine and 1-2 chemotherapies: Dato-DXd vs chemotherapy. People in a different situation may not see the same effect.
  • The trial selected people by a biomarker (HER2); the result should not be assumed for people whose cancer does not have it.

Numbers are from the trial as recorded here; see the source links in the table below. This is orientation, not medical advice: ask your team how closely the trial population matches you.

732 participants enrolled.

Progression-free survival (BICR)primary
HR 0.63 (0.52–0.76) · p <0.0001
Datopotamab deruxtecan
6.9 mo
Chemotherapy (ICC)
4.9 mo
Source
Overall survivalprimary
HR 1.01 (0.83–1.22)
Datopotamab deruxtecan
18.6 mo
Chemotherapy (ICC)
18.3 mo

Not significant

Source
Objective response rate
Datopotamab deruxtecan36.4 of 100
Chemotherapy (ICC)22.9 of 100
EndpointArmnValueHR (95% CI)pSource
Progression-free survival (BICR)primaryDatopotamab deruxtecan3656.9 months0.63 (0.52–0.76)<0.0001link
Chemotherapy (ICC)3674.9 months
Overall survivalprimaryDatopotamab deruxtecan18.6 months1.01 (0.83–1.22)link
Chemotherapy (ICC)18.3 months
Objective response rateDatopotamab deruxtecan36.4%
Chemotherapy (ICC)22.9%
Replication
PFS-only benefit; the OS result did not replicate the PFS signal. The HR+ population is also served by TROPiCS-02 (sacituzumab), which did show an OS benefit.

Key papers

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Connected

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Pages like this

not linked directly; found by shared links