Clinical trial · Interventional
Study to Evaluate Exemestane With and Without Entinostat (SNDX-275) in Treatment of Postmenopausal Women With Advanced Breast Cancer
A Phase 2, Randomized, Double-Blind, Multicenter Study of Exemestane With and Without SNDX-275 in Postmenopausal Women With Locally Recurrent or Metastatic Estrogen Receptor-Positive Breast Cancer, Progressing on Treatment With a Non-Steroidal Aromatase Inhibitor
NCT00676663CI-TRIAL-00058420ENCORE301completedPhase 2Results postedClinicalTrials.gov clinicaltrialsProvenance
- Source
- ClinicalTrials.gov
- Retrieved
- Sep 8, 2026
- Layer
- normalized (units and labels harmonized; values unchanged)
- Run
- ING-CLINICALTRIALS-20260908-000001
Summary
Brief summary (as posted)
The purpose of this study is to evaluate the safety and efficacy of entinostat in combination with exemestane in the treatment of advanced breast cancer.
Conditions
Conditions (4)
Free-text conditions as registered, with the CancerIndex entity they were reconciled to and the match type.
| Condition (as posted) | Mapped entity | Match | Confidence |
|---|---|---|---|
| Breast Cancer | Malignant Breast Neoplasm | CURATED_EXACT | 0.92 |
| Breast Cancer, Estrogen Receptor-Positive | Malignant Breast Neoplasm | CURATED_EXACT | 0.85 |
| ER+ Breast Cancer | — | UNRESOLVED | — |
| Estrogen Receptor-Positive Breast Cancer | — | UNRESOLVED | — |
Interventions
Interventions (3)
| Intervention | Type | Mapped drug | Match |
|---|---|---|---|
| entinostat | Drug | — | UNRESOLVED |
| exemestane | Drug | Exemestane | ALIAS |
| Placebo | Drug | — | UNRESOLVED |
Design
Arms and outcomes
Arms (2)
- type
- EXPERIMENTAL
- label
- Exemestane 25 mg + Entinostat 5 mg
- description
- Exemestane (Aromasin®) 25 mg tablets orally once daily plus an entinostat 5 mg tablet orally once per week on Days 1, 8, 15 and 22 of each 28-day treatment cycle until development of progressive disease (PD) or unacceptable toxicity or closure of the study by the Sponsor, whichever occurred first.
- interventionNames
- Drug: entinostat
- Drug: exemestane
- type
- PLACEBO_COMPARATOR
- label
- Exemestane 25 mg + Placebo
- description
- Exemestane (Aromasin®) 25 mg tablets orally once daily plus a placebo-matching entinostat tablet orally once per week on Days 1, 8, 15 and 22 of each 28-day treatment cycle until development of progressive disease (PD) or unacceptable toxicity or closure of the study by the Sponsor, whichever occurred first.
- interventionNames
- Drug: exemestane
- Drug: Placebo
Primary outcomes (1)
Eligibility
Eligibility (as posted)
- Sex
- Female
- Minimum age
- 18 Years
Show eligibility criteria text
Inclusion Criteria: * Postmenopausal female patients * Histologically or cytologically confirmed estrogen receptor positive (ER+) breast cancer * Relapsed or progressed on prior treatment with aromatase inhibitor (AI) * Metastatic disease must be measurable * Patients receiving palliative radiation at the non-target lesions must have a 2 week wash out period following completion of the treatment prior to enrollment * Patient may have had one prior chemotherapy as part of first line therapy as long as it was received before initiation of prior AI * Eastern Cooperative Oncology Group (ECOG) performance status: 0 to 1 * Laboratory parameters: a)Hemoglobin ≥ 9.0 g/dL; platelets ≥ 100.0 x 10\^9/L; Absolute Neutrophil Count (ANC ≥) 1.5 x 10\^9/L without the use of hematopoietic growth factors b)Creatinine less than 2.5 times the upper limit of normal for the institution c)Aspartate transaminase (AST) and alanine transaminase (ALT) less than 2.5 times the upper limit of normal for the institution * Able to understand and give written informed consent and comply with study procedures Exclusion Criteria: * Relapse on treatment with non-steroidal AI after less than 12 months for patients in the adjuvant setting * Progressive disease after less than 3 months treatment with most recent AI for patients with metastatic disease * Rapidly progressive, life-threatening metastases * Any palliative radiotherapy to the measurable lesion * Previous treatment with SNDX-275 or any other histone deacetylase (HDAC) inhibitor including valproic acid * Allergy to benzamides or inactive components of the study drug * A history of allergies to any active or inactive ingredients of exemestane * Any concomitant medical condition that precludes adequate study treatment compliance * Patient is currently enrolled in (or completed within 30 days before study drug administration) another investigational drug study * Patient is currently receiving treatment with valproic acid, Zolinza (vorinostat) or any other HDAC inhibitor or deoxyribonucleic acid (DNA) methyltransferase inhibitor or any systemic anticancer treatment (with the exception of Lupron)
References
Publications (1)
- DERIVEDYardley DA, Ismail-Khan RR, Melichar B, Lichinitser M, Munster PN, Klein PM, Cruickshank S, Miller KD, Lee MJ, Trepel JB. Randomized phase II, double-blind, placebo-controlled study of exemestane with or without entinostat in postmenopausal women with locally recurrent or metastatic estrogen receptor-positive breast cancer progressing on treatment with a nonsteroidal aromatase inhibitor. J Clin Oncol. 2013 Jun 10;31(17):2128-35. doi: 10.1200/JCO.2012.43.7251. Epub 2013 May 6. PMID 23650416