Emulation of the PALOMA-2 Trial

NCT07178743 | Active Not Recruiting FDA Drug

• 2 other identifiers: 2022P002556-ENC-PALOMA275F40122C00181
• Study Type: observational
• Target: 6,097
• Locations: 1 country
• Sites: 1

Brief Summary

Investigators are building an empirical evidence base for real world data through large-scale emulation of randomized controlled trials. The investigators' goal is to understand for what types of clinical questions real world data analyses can be conducted with confidence and how to implement such studies.

Conditions

Advanced Breast Cancer

Outcome Measures

Primary Outcomes (1)

• Time to all-cause mortality (overall survival)

  Hazard ratio (95% CI)

  Through the earliest of outcome, censoring, or end of data (April 2024)

Secondary Outcomes (1)

• Time to next treatment (TTNT)

  Through the earliest of outcome, censoring, or end of data (April 2024)

Study Arms (2)

Initiation of palbociclib plus letrozole

Exposure group

Drug: Initiation of palbociclib plus letrozole

Initiation of letrozole

Reference group

Drug: Initiation of letrozole

Interventions

Initiation of palbociclib plus letrozole DRUG

Initiation of palbociclib plus letrozole described in electronic health records is used as the exposure.

Initiation of palbociclib plus letrozole

Initiation of letrozole DRUG

Initiation of letrozole described in electronic health records is used as the reference.

Initiation of letrozole

Eligibility Criteria

• Age: 18 Years+
• Sex: female
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

Postmenopausal women with ER-positive, HER2-negative locally advanced or metastatic breast cancer who receive treatment without curative intent

You may qualify if:

• Age ≥18 years
• Postmenopausal women with ER-positive, HER2-negative locally advanced or metastatic breast cancer who receive treatment without curative intent
• The line of therapy for patients in EDB1 and EDB3 is implicitly advanced/metastatic because the line of therapy classification starts after their advanced/metastatic diagnosis in the respective database
• In EDB4, patients must explicitly have any evidence of a metastasis prior initiating palbociclib plus letrozole or letrozole alone
• Adenocarcinoma histology
• No prior systemic treatment for advanced/metastatic disease
• ECOG performance status of 0 or 1

You may not qualify if:

• HER2+
• CNS metastases
• Prior treatment with CDK4/6 inhibitor
• Non-breast cancer malignancy other than basal/squamous cell skin cancer or carcinoma in situ of cervix
• Systemic anticancer therapy other than palbocicilib or letrozole
• Treatment with non-steroidal aromatase inhibitor (i.e.anastrozole, letrozole)

Sponsors & Collaborators

• Food and Drug Administration (FDA): collaborator
• Brigham and Women's Hospital: lead

Study Sites (1)

Brigham and Women's Hospital

Boston, Massachusetts, 02120, United States

Location

MeSH Terms

Interventions

Letrozole

Intervention Hierarchy (Ancestors)

Nitriles; Organic Chemicals; Triazoles; Azoles; Heterocyclic Compounds, 1-Ring; Heterocyclic Compounds

Study Officials

• Shirley Wang, PhD, ScM

  Brigham and Women's Hospital

  PRINCIPAL INVESTIGATOR

• Denys Shay, MD

  Brigham and Women's Hospital

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: RETROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Associate Professor

Study Record Dates

• First Submitted: September 8, 2025
• First Posted: September 17, 2025
• Study Start: July 14, 2025
• Primary Completion: March 1, 2026
• Study Completion: March 1, 2026
• Last Updated: January 30, 2026

Record last verified: 2025-09

Locations

US (1)