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Brought enzalutamide into first-line metastatic treatment, with an overall survival benefit confirmed in 2021.

1,150 men; rPFS HR 0.39; OS HR 0.66 at final analysis. ENZAMET (ANZUP) confirmed independently.

Setting
Metastatic hormone-sensitive prostate cancer: ADT + enzalutamide vs ADT
Phase
Phase 3
Sponsor
Astellas / Pfizer
Registry
NCT02677896
Headline result
rPFS HR 0.39; OS HR 0.66.
Reported
2019
Enrolled
1150
Replication
Replicated by ENZAMET (enzalutamide) and TITAN (apalutamide).

Outcomes

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In plain words
What these results mean for people, not percentages
1,150 people took part
Radiographic progression-free survivalprimarysurrogate endpoint
  • Median 19 months with ADT + placebo.
  • ADT + enzalutamide: Median not reached.
  • "Not reached" means that, when the data were analysed, more than half of that group had not yet had the event, which is good news for that group.
  • A median is a midpoint: half the people did better than this and half did worse.
  • Put another way, the treated group had about 61 percent lower chance of the event at any given time (hazard ratio 0.39, likely range 0.3 to 0.5).
  • 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 survivalsurvival endpoint
  • The treated group had about 34 percent lower chance of the event at any given time (hazard ratio 0.66).
  • The absolute difference, how many more people out of 100 were helped, is not reported here.
  • Medians not reached at the final analysis
  • Overall survival counts deaths from any cause, so it is the most direct measure of whether a treatment helps people live longer.
Be careful
  • These results apply to the people the trial enrolled: Metastatic hormone-sensitive prostate cancer: ADT + enzalutamide vs ADT. People in a different situation may not see the same effect.

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.

1,150 participants enrolled.

Radiographic progression-free survivalprimary
HR 0.39 (0.3–0.5) · p <0.001
ADT + enzalutamide
Median not reached
ADT + placebo
19 mo

Median not reached

Source
Overall survival
HR 0.66 (0.53–0.81)

Medians not reached at the final analysis

Source
EndpointArmnValueHR (95% CI)pSource
Radiographic progression-free survivalprimaryADT + enzalutamide574Median not reached0.39 (0.3–0.5)<0.001link
ADT + placebo57619 months
Overall survivalADT + enzalutamide—Medians not reached at the final analysis0.66 (0.53–0.81)—link
ADT + placebo——
Replication
Replicated by ENZAMET (enzalutamide) and TITAN (apalutamide).

Connected

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Pages like this

not linked directly; found by shared links

cancers

1
Prostate cancer

drugs

1
ApprovedSmall-molecule AR antagonist
Enzalutamide · Xtandi