OncoMatch/Clinical Trials/NCT05933395
Genetically-informed Therapy for ER+ Breast Cancer Post-CDK4/6 Inhibitor
Is NCT05933395 recruiting? Yes, currently enrolling (Jun 2026). This Phase 2 trial studies multiple treatments for advanced breast cancer.
Treatment: Fulvestrant · Neratinib · Alpelisib · Everolimus · Abemaciclib — The purpose of this study is to learn if certain drug combinations are effective treatments for patients with advanced ER+/HER2- who have previously been treated with palbociclib, ribociclib, or abemaciclib.
Check if I qualifyExtracted eligibility criteria
Treatments studied
Targeted therapy
Endocrine / hormonal
Cancer type
Breast Carcinoma
Biomarker criteria
Required: ESR1 overexpression (IHC ≥1% of malignant cell nuclei)
ER+ status defined as ER staining by immunohistochemistry in ≥1% of malignant cell nuclei
Required: HER2 (ERBB2) non-amplified (IHC 0-1+ or FISH ratio <2 if IHC is 2+ or not done)
Tumor must be HER2-non-amplified as defined by an immunohistochemistry score of 0-1+, or with a FISH ratio <2 if IHC is 2+ or if IHC has not been done (as per ASCO/CAP definitions)
Allowed: HER2 (ERBB2) study-relevant alteration
Profiling must minimally include analysis of study-relevant alterations in ERBB2, PIK3CA, AKT1, MTOR, PTEN, and RB1
Allowed: PIK3CA study-relevant alteration
Profiling must minimally include analysis of study-relevant alterations in ERBB2, PIK3CA, AKT1, MTOR, PTEN, and RB1
Allowed: AKT1 study-relevant alteration
Profiling must minimally include analysis of study-relevant alterations in ERBB2, PIK3CA, AKT1, MTOR, PTEN, and RB1
Allowed: MTOR study-relevant alteration
Profiling must minimally include analysis of study-relevant alterations in ERBB2, PIK3CA, AKT1, MTOR, PTEN, and RB1
Allowed: PTEN study-relevant alteration
Profiling must minimally include analysis of study-relevant alterations in ERBB2, PIK3CA, AKT1, MTOR, PTEN, and RB1
Allowed: RB1 study-relevant alteration
Profiling must minimally include analysis of study-relevant alterations in ERBB2, PIK3CA, AKT1, MTOR, PTEN, and RB1
Demographics
Prior therapy
Must have received: CDK4/6 inhibitor (palbociclib, ribociclib, abemaciclib) — advanced disease
Patient must have been treated with a CDK4/6i (either palbobclib, ribociclib, or abemaciclib) alone or in combination with an endocrine agent in the advanced disease setting
Cannot have received: CDK4/6 inhibitor (abemaciclib)
Exception: exclusion applies only if abemaciclib was the most recent or current line of therapy
Treatment with abemaciclib in the most recent or current line of therapy
Cannot have received: investigational cancer therapy
Exception: within the last 3 weeks
Any investigational cancer therapy in the last 3 weeks
Structured fields extracted by AI. May contain errors — verify against the official protocol.
US trial sites
- Dartmouth Hitchcock Medical Center · Lebanon, New Hampshire
Showing up to 5 US sites.
See all sites on ClinicalTrials.gov →Frequently asked questions
Is NCT05933395 currently recruiting?
Yes, this trial is currently recruiting patients.
Are there prior therapy exclusions?
Yes. Prior CDK4/6 inhibitor, investigational cancer therapy disqualifies patients from enrollment.
Does this trial require ESR1?
Yes, ESR1 overexpression is a required biomarker for enrollment.
Does this trial require ERBB2?
Yes, ERBB2 non-amplified is a required biomarker for enrollment.
Is this trial open to male patients?
No. This trial enrolls female patients only.
Could you qualify for this trial?
Enter your biomarker results to see how this trial's eligibility criteria match your specific cancer profile.
Check if I qualify