A Comparative Study of AZD9833 Plus Palbociclib Versus Anastrozole Plus Palbociclib in Patients With ER-Positive HER2 Negative Breast Cancer Who Have Not Received Any Systemic Treatment for Advanced Disease
← catalyst calendarNCT04711252 · readout in 5 d
Sponsored by AstraZeneca (industry) · AZN — their whole pipeline →.
Phase
Phase 3
Status
Active, not recruiting
Study type
Interventional
Design
Randomized · Triple · Treatment
Enrollment
1,370actual
Sites
263
Countries
Austria, Belgium, Bulgaria +24
Every value on this page is a field the sponsor filed with ClinicalTrials.gov, reproduced. Dates are their own estimates, revised as a study runs, unless the registry marks them actual. sources →
Source: ClinicalTrials.gov, retrieved 2026-08-19
Dates
each axis at the precision it was filed, with the registry's own basis| Date | Filed | Basis | What it is |
|---|---|---|---|
| Start | 2021-01-28 | actual | When the study began enrolling |
| Primary completion | 2026-08-24 | estimated | The date the last participant is measured for the primary outcome — the readout window |
| Study completion | 2029-02-01 | estimated | The whole study's end, after follow-up |
| First posted | 2021-01-15 | actual | When this record first appeared on the registry |
| Results posted | — | When the sponsor posted results to the registry | |
| Record updated | 2025-10-14 | actual | The sponsor's own last edit to this record — every projection above is as current as this date |
What it studies
Condition
- ER-Positive HER2-Negative Breast Cancer
Interventions
- Drug: AZD9833
- Drug: Anastrozole
- Drug: Anastrozole placebo
- Drug: AZD9833 placebo
- Drug: Palbociclib
- Drug: Luteinizing hormone-releasing hormone (LHRH) agonist
Primary outcome
what the primary-completion date above is the date OFProgression-free survival (PFS) assessed by the Investigator as defined by response evaluation criteria in solid tumors (RECIST) version 1.1
measured From randomization until progression per RECIST 1.1 as assessed by the investigator at local site or death due to any cause (up to 5 years)
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