TACTIVE-U: A Study to Learn About the Study Medicine (Vepdegestrant) When Given With Other Medicines in People With Advanced or Metastatic Breast Cancer (Sub-Study B)
← catalyst calendarNCT05573555 · readout in 133 d
Sponsored by Pfizer (industry) · PFE — their whole pipeline →. With Arvinas Estrogen Receptor, Inc..
Phase
Phase 1/2
Status
Active, not recruiting
Study type
Interventional
Design
Na · None · Treatment
Enrollment
20actual
Sites
29
Countries
Canada, Italy, Spain +1
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 | 2023-03-01 | actual | When the study began enrolling |
| Primary completion | 2026-12-30 | estimated | The date the last participant is measured for the primary outcome — the readout window |
| Study completion | 2026-12-30 | estimated | The whole study's end, after follow-up |
| First posted | 2022-10-10 | actual | When this record first appeared on the registry |
| Results posted | — | When the sponsor posted results to the registry | |
| Record updated | 2026-03-09 | actual | The sponsor's own last edit to this record — every projection above is as current as this date |
What it studies
Condition
- Breast Cancer
Interventions
- Drug: ARV-471
- Drug: Ribociclib
Primary outcomes
what the primary-completion date above is the date OFPhase 1b: Number of Participants With Dose Limiting Toxicities
measured Cycle 1 (28 days)
Phase 2: Percentage of Participants With Objective Response by investigator assessment
measured Up to approximately 1 year
Drug Drug Interaction cohort: Area Under the Curve from Time Zero to end of dosing interval Evaluation of ribociclib with and without co-administration of ARV-471
measured pre-dose Day -1, 1, 8, 15, 29, 43, 57, 113, 169; 1, 2, 4, 6, 8 hours post dose on Day -1 and 15; post dose Day 8, 29 and 43
Drug Drug Interaction cohort: Maximum Plasma Concentration (Cmax) of ribociclib with and without co-administration of ARV-471
measured pre-dose Day -1, 1, 8, 15, 29, 43, 57, 113, 169; 1, 2, 4, 6, 8 hours post dose on Day -1 and 15; post dose Day 8, 29 and 43
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