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OncoMatch/Clinical Trials/NCT06366347

ALPINE: Maintenance Letrozole/Abemaciclib

Is NCT06366347 recruiting? Yes, currently enrolling (Jun 2026). This Phase 2 trial studies multiple treatments including Abemaciclib and Letrozole for endometrial cancer.

Phase 2RecruitingDana-Farber Cancer InstituteNCT06366347Data as of Jun 2026

Treatment: Abemaciclib · Letrozole · PembrolizumabThe purpose of this research study is to see if the study drugs abemaciclib and letrozole are effective and safe for participants with estrogen-receptor positive (ER+), mismatch repair proficient, tumor protein p53 (TP53) wild-type endometrial cancer. The names of the study drugs involved in this study are: * Abemaciclib (a type of cyclin-dependent kinase (CDK) inhibitor) * Letrozole (a type of aromatase inhibitor)

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Extracted eligibility criteria

Treatments studied

Immunotherapy

Pembrolizumab

Targeted therapy

Abemaciclib

Endocrine / hormonal

Letrozole

Cancer type

Endometrial Cancer

Biomarker criteria

Required: ESR1 overexpression (≥ 1 percent of tumor cell nuclei immunoreactive by IHC)

Participants must have ER-positive disease, defined as ≥ 1 percent of tumor cell nuclei being immunoreactive by immunohistochemistry (IHC)

Required: TP53 wild-type

Tumor must be TP53 wild-type as determined by immunohistochemistry (IHC) or via CLIA-certified targeted Next-Generation Sequencing (NGS)

Excluded: RB1 mutation

No known RB1 mutations

Excluded: RB1 two-copy deletion

No known...two-copy RB1 deletion

Disease stage

Required: Stage III, IVA, IVB

measurable stage III, measurable stage IVA, stage IVB (with or without measurable disease) or recurrent (with or without measurable disease) endometrial cancer

Performance status

ECOG 0–2(Ambulatory, capable of self-care)

Prior therapy

Must have received: platinum-based chemotherapy (carboplatin) — combination with taxane or with taxane and anti-PD-(L)1 inhibitor

Participants must have just completed a minimum of 4 cycles and a maximum of 10 cycles of a combination of carboplatin and taxane or a combination of taxane and anti-PD-(L)1 inhibitor therapy

Must have received: taxane — combination with carboplatin or with anti-PD-(L)1 inhibitor

Participants must have just completed a minimum of 4 cycles and a maximum of 10 cycles of a combination of carboplatin and taxane or a combination of taxane and anti-PD-(L)1 inhibitor therapy

Cannot have received: CDK4/6 inhibitor (abemaciclib)

Participants who have received previous treatment with CDK4/6 inhibitors, including but not limited to previous abemaciclib therapy

Lab requirements

Blood counts

ANC ≥1.5 × 10^9 /L; Platelets ≥100 × 10^9 /L; Hemoglobin ≥8 g/dL (transfusions allowed)

Kidney function

Creatinine ≤ 1.5 × institutional ULN, OR Creatinine clearance ≥ 60 mL/min/1.73 m2 for participants with creatinine levels above 1.5 x institutional ULN

Liver function

Total bilirubin ≤1.5 × ULN (≤2.0 × ULN with Gilbert's syndrome and direct bilirubin within normal limits); ALT and AST ≤3 × ULN

Participants must have normal organ and bone marrow function within 2 weeks before starting protocol therapy as defined below: Hematologic: ANC ≥1.5 × 10^9 /L; Platelets ≥100 × 10^9 /L; Hemoglobin ≥8 g/dL... Hepatic: Total bilirubin ≤1.5 × ULN... ALT and AST ≤3 × ULN... Renal: Creatinine ≤ 1.5 × institutional ULN, OR Creatinine clearance ≥ 60 mL/min/1.73 m2...

Structured fields extracted by AI. May contain errors — verify against the official protocol.

US trial sites

  • Beth Israel Deaconess Medical Center · Boston, Massachusetts
  • Brigham and Women's Hospital · Boston, Massachusetts
  • Dana-Farber Cancer Institute · Boston, Massachusetts
  • Dana-Farber Cancer Institute at Foxborough · Foxborough, Massachusetts
  • Dana-Farber Cancer Institute at Milford · Milford, Massachusetts

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See all sites on ClinicalTrials.gov →

Frequently asked questions

Is NCT06366347 currently recruiting?

Yes, this trial is currently recruiting patients.

Are there prior therapy exclusions?

Yes. Prior CDK4/6 inhibitor disqualifies patients from enrollment.

Does this trial require ESR1?

Yes, ESR1 overexpression is a required biomarker for enrollment.

Does this trial require TP53?

Yes, TP53 wild-type is a required biomarker for enrollment.

Are patients with RB1 alterations eligible?

No. RB1 mutation is an exclusion criterion.

Are patients with RB1 alterations eligible?

No. RB1 two-copy deletion is an exclusion criterion.

What disease stage is eligible?

Stage III or IVA or IVB is required.

Could you qualify for this trial?

Enter your biomarker results to see how this trial's eligibility criteria match your specific cancer profile.

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