OP-1250 (Palazestrant) vs. Standard of Care for the Treatment of ER+/HER2- Advanced Breast Cancer

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NCT06016738 · readout in 73 d

Sponsored by Olema Pharmaceuticals, Inc. (industry) · OLMA — their whole pipeline →.

Phase

Phase 3

Status

Active, not recruiting

Study type

Interventional

Design

Randomized · None · Treatment

Enrollment

510estimated

Sites

233

Countries

Argentina, Australia, Austria +23

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

2023-11-16

actual

When the study began enrolling

Primary completion

2026-10-31

estimated

The date the last participant is measured for the primary outcome — the readout window

Study completion

2028-02-29

estimated

The whole study's end, after follow-up

First posted

2023-08-30

actual

When this record first appeared on the registry

Results posted

—

When the sponsor posted results to the registry

Record updated

2026-08-13

actual

The sponsor's own last edit to this record — every projection above is as current as this date

What it studies

Conditions

Breast Cancer
Advanced Breast Cancer
Metastatic Breast Cancer
ER Positive Breast Cancer
HER2 Negative Breast Carcinoma

Interventions

Drug: Palazestrant — also filed as OP-1250
Drug: Fulvestrant
Drug: Anastrozole
Drug: Letrozole
Drug: Exemestane

Primary outcomes

what the primary-completion date above is the date OF

Dose-Selection Part: Incidence of adverse events

measured From Date of Randomization up to 16 weeks

Dose-Selection Part: Incidence of dose reduction

measured From Date of Randomization up to 16 weeks

Dose-Selection Part: Incidence of drug discontinuation

measured From Date of Randomization up to 16 weeks

Trial: Progression-Free Survival (PFS)

measured From Date of Randomization until Disease Progression or Death Due to Any Cause (estimated as up to 2 years)

Publications

PMID 41461598 — linked by the registry

Linked on the registry record. A “linked by the registry” entry is NLM's own automated PubMed match, not a claim by the sponsor that the paper reports this study.

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