A Window-of-Opportunity Trial of Giredestrant +/- Triptorelin vs. Anastrozole + Triptorelin in Premenopausal Patients With ER-positive/HER2-negative Early Breast Cancer

What Was Tested

In this phase 2 trial, researchers set out to test Triptorelin.

PREcoopERA is a randomized (2:2:1), multicenter, open-label, three-arm (A, B, C), Window-of-Opportunity (WOO) trial to evaluate the activity and safety of giredestrant (A) versus giredestrant plus triptorelin (B) versus anastrozole plus triptorelin (C).

It had three arms (groups): Arm A: Giredestrant (experimental), Arm B: Giredestrant plus triptorelin (experimental) and Arm C: Anastrozole plus triptorelin (active comparator).

Giredestrant.

Giredestrant plus triptorelin.

Anastrozole plus triptorelin.

The registry classes the interventions as drug.

Who Took Part

The registry lists 231 actual participants took part.

It was open to women only aged from 18 years with no upper age limit.

Healthy volunteers were not accepted; participants needed the condition being studied.

Examples of who could join: Premenopausal women age ≥18 years, premenopausal status defined as:. Histologically confirmed, operable invasive breast carcinoma. Documented human epidermal growth factor receptor-2 (HER2)-negative tumor in accordance to 2018 ASCO/CAP guidelines (Wolff et al. 2018)48, as determined per local assessment. Eastern Cooperative Oncology Group Performance Status 0-1. Resting heart rate ≥40 bpm.

The full record lists 16 inclusion and 21 exclusion criteria; among the exclusions: stage iv (metastatic) breast cancer; inflammatory breast cancer (ct4d); previous systemic or local treatment for the primary breast cancer currently under investigation.

How the Study Was Run

The set-up was randomized, parallel-group and open-label.

The participants were allocated by chance, so the Triptorelin group and the comparison group should start out alike.

Groups ran in parallel: each of the participants stayed in one arm throughout.

Nothing was hidden in this open-label Triptorelin study: the participants and staff both knew the treatment.

It started in 2024-01-23 with completion listed for 2025-09-18.

It ran at 37 sites in Italy (11), Germany (10), Switzerland (8), Spain (5), Ireland (2) and France (1).

Its stated primary purpose is treatment.

What Was Measured

The main thing measured (primary outcome): Change in Ki 67 (time frame: From date of randomisation until 29 ±3 days post-randomisation).

It also tracked 2 secondary outcomes, for example Complete cell cycle arrest (CCCA) and Adverse events according to CTCAE v5.0.

What This Means in Plain Language

Put simply, this is a phase 2, randomized trial of Triptorelin in 231 people.

The trial is marked completed; no results are posted to the registry yet, so nothing here describes outcomes.

More context: the Triptorelin compound page, all human trials.