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NCT05508906 · ClinicalTrials.gov registry record · Phase 1

Phase 1b Study of OP-1250 (Palazestrant) in Combination With Ribociclib, Alpelisib, Everolimus, or Atirmociclib in ER+, HER2- Breast Cancer

A Phase 1 study of Breast Cancer and Metastatic Breast Cancer, sponsored by Olema Pharmaceuticals.

Recruiting
Registry status
Phase 1
Development phase
190
Enrollment target
16
Study locations

NCT05508906: Recruiting Phase 1 study of Breast Cancer and Metastatic Breast Cancer, sponsored by Olema Pharmaceuticals.

NCT05508906 is a Phase 1 study of Breast Cancer and Metastatic Breast Cancer that is actively recruiting participants, run by Olema Pharmaceuticals. The registered enrollment target is 190 participants, below the 2,803-participant average among 1,224 other Breast Cancer trials with a reported enrollment target (93% lower). The trial reports 16 study locations across 16 states. According to ClinicalTrials.gov, the official US trial registry.

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The verdict

NCT05508906, a Phase 1 study of Breast Cancer and Metastatic Breast Cancer, is actively recruiting participants, sponsored by Olema Pharmaceuticals.

RECRUITING
Registry status
Phase 1
Development phase
190 participants
Enrollment target
16
Study locations

Study Summary

This is a Phase 1b open-label, 2-part study in 3 treatment groups. The 3 treatment groups are as follows: Treatment Group 1: Palazestrant (OP-1250) in combination with ribociclib (KISQALI®, Novartis Pharmaceuticals Corporation). Treatment Group 2: Palazestrant (OP-1250) in combination with alpelisib (PIQRAY®, Novartis Pharmaceuticals Corporation). Treatment Group 3: Palazestrant (OP-1250) in combination with everolimus. Treatment Group 4: Palazestrant (OP-1250) in combination with atirmociclib.

Primary Outcome

To determine the maximum tolerated dose (MTD) and/or recommended Phase 2 dose (RP2D), and/ or recommended dose expansion (RDE) of palazestrant when administered with ribociclib (Treatment Group 1), alpelisib (Treatment Group 2), or everolimus (Treatment Group 3), or atirmociclib (Treatment Group 4). The incidence of DLTs will be assessed in the Dose Escalation part (Part 1) of the study.

Interventions

  • DRUG Everolimus
  • DRUG Ribociclib
  • DRUG Alpelisib
  • DRUG Palazestrant
  • DRUG Atirmociclib

Study Locations (16)

Arizona

  • Banner MD Anderson Cancer Center - Gilbert

California

  • University of California San Francisco Health - San Francisco

Colorado

  • University of Colorado Cancer Center - Aurora

Florida

  • Advent Health Hematology and Oncology - Orlando

Iowa

  • University of Iowa - Iowa City

Massachusetts

  • Dana Farber Cancer Institute - Boston

Michigan

  • Henry Ford Health - Detroit

Minnesota

  • Regents of the University of Minnesota - Minneapolis

Trial Details

FieldValue
Enrollment Target 190 participants
Start Date 2022-08-31
Est. Completion 2028-01-31
Phase Phase 1
Olema Pharmaceuticals

5 total trials

What NCT05508906 shows while recruiting

NCT05508906 is an interventional study that assigns participants to a tested intervention. The registered 190 participants enrollment target is mid-sized for trials with a published cap, below the 2,803-participant average among 1,224 other Breast Cancer trials with a reported enrollment target (93% lower).

The record links to 5 conditions, with Breast Cancer appearing as the primary indexed condition, and to 5 interventions - of which Everolimus is the first listed.

NCT05508906 lists 16 locations in 16 states (Arizona, California, Colorado).

Frequently Asked Questions

What is clinical trial NCT05508906 about?

NCT05508906 is a clinical study titled "Phase 1b Study of OP-1250 (Palazestrant) in Combination With Ribociclib, Alpelisib, Everolimus, or Atirmociclib in ER+, HER2- Breast Cancer". This is a Phase 1b open-label, 2-part study in 3 treatment groups. The 3 treatment groups are as follows: Treatment Group 1: Palazestrant (OP-1250) in combination with ribociclib (KISQALI®, Novartis Pharmaceuticals Corporation). Treatment Group 2: Palazestrant (OP-1250) in combination with alpelis...

What is the current status of trial NCT05508906?

This trial is currently recruiting. It is a Phase 1 study. The enrollment target is 190 participants. The study started on 2022-08-31. Estimated completion is 2028-01-31.

What conditions does trial NCT05508906 study?

This clinical trial studies the following conditions: Breast Cancer, Metastatic Breast Cancer, HER2-Negative Breast Cancer, ER Positive Breast Cancer, Locally Advanced Breast Cancer.

What interventions are being tested in trial NCT05508906?

The interventions under investigation include: Everolimus (DRUG), Ribociclib (DRUG), Alpelisib (DRUG), Palazestrant (DRUG), Atirmociclib (DRUG).

Who is sponsoring clinical trial NCT05508906?

This trial is sponsored by Olema Pharmaceuticals, which has 5 total clinical trials registered on ClinicalTrials.gov.

Where is trial NCT05508906 being conducted?

This trial has 16 study locations across Arizona, California, Colorado, Florida, Iowa. Contact the study sites directly through ClinicalTrials.gov for enrollment availability.

Similar trials for Breast Cancer

Matched on the same primary condition, ranked to surface studies in the same phase first, then by recruiting status, no relevance scoring or editorial curation.

Where NCT05508906's enrollment target sits among peer trials

190 391st of 1224 higher than 832 of 1,224 other Breast Cancer trials

participants (enrollment target), bucketed by value

Each bar is a band; taller bars hold more other Breast Cancer trials. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.

Source ClinicalTrials.gov registry export · 2026-08-08

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Source: ClinicalTrials.gov NCT05508906, the US trial registry maintained by the National Library of Medicine. NCT05508906 (mid enrollment · multi site footprint · recruiting) retrieved and formatted by PlainTrial, see methodology.