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NCT04872608
A Study of Letrozole, Palbociclib, and Onapristone ER in People With Metastatic Breast Cancer
Phase 1 trial testing Letrozole in Metastatic Breast Cancer. Withdrawn.
25 April 2023
Quick facts
| Lead sponsor | Memorial Sloan Kettering Cancer Center |
|---|---|
| Phase | Phase 1 |
| Status | Withdrawn |
| Study type | INTERVENTIONAL |
| Allocation | na |
| Design | single group |
| Masking | none |
| Primary purpose | treatment |
| Start date | 9 September 2021 |
| Primary completion | 25 April 2023 |
| Estimated completion | 25 April 2023 |
| Sites | 1 location across United States |
Drugs / interventions tested
- Letrozole — full drug profile →
- Palbociclib (Palbociclib) — full drug profile →
- Onapristone ER — full drug profile →
Conditions studied
- Metastatic Breast Cancer — all drugs for Metastatic Breast Cancer →
- Unresectable Breast Cancer — all drugs for Unresectable Breast Cancer →
Sponsor
Memorial Sloan Kettering Cancer Center — full company profile →
Who can join
18 and older, female only, with Metastatic Breast Cancer or Unresectable Breast Cancer. Patients with the condition only — healthy volunteers not accepted.
Sponsor's own description
The researchers are doing this study to find out whether the study drug onapristone ER, combined with the standard treatment for your cancer (letrozole and palbociclib), is a safe treatment for people who have metastatic or unresectable ER+/PR+/HER2- breast cancer. The researchers will test different doses of the study drug to find the highest dose that causes few or mild side effects.
Publications & conference data
2 peer-reviewed publications reference this trial (live from Europe PMC):
-
Novel pentacyclic derivatives and benzylidenes of the progesterone series cause anti-estrogenic and antiproliferative effects and induce apoptosis in breast cancer cells.
Scherbakov AM, Vorontsova SK, Khamidullina AI, Mrdjanovic J, et al · · 2023 · cited 24× · PMID 36695998 · DOI 10.1007/s10637-023-01332-z -
Beyond traditional biopsies: the emerging role of ctDNA and MRD on breast cancer diagnosis and treatment.
Sabit H, Attia MG, Mohamed N, Taha PS, et al · · 2025 · cited 4× · PMID 40050490 · DOI 10.1007/s12672-025-01940-6
Verify or expand the search:
- PubMed search for NCT04872608
- Europe PMC full search
- ASCO Meeting Library
- ESMO Meeting Library
- bioRxiv preprints
- medRxiv preprints
- Google Scholar
Related trials
Other trials of Letrozole
Trials testing the same drug.
- NCT07391774 — Testing Whether Hormone Therapy With Ribociclib is as Effective as Chemotherapy Followed by Hormone Therapy With Ribocic · Phase 3 · not yet recruiting
- NCT07570966 — Study of ERW316 as a Single Agent or in Combination With Endocrine Therapy in Patients With HR+/HER2- Breast Cancer and · Phase 1, PHASE2 · not yet recruiting
- NCT07492641 — BGB-43395 Plus Letrozole Versus CDK4/6i Plus Letrozole for Patients With Advanced or Metastatic HR+/HER2- Breast Cancer · Phase 3 · not yet recruiting
- NCT06905301 — Implementation Study to Describe and Compare Retention Rate and Adherence to Adjuvant Therapy With Ribociclib With and W · recruiting
- NCT07288359 — Study of GVV858 as a Single Agent or in Combination With Endocrine Therapy in Patients With HR+/HER2- Breast Cancer and · Phase 1, PHASE2 · recruiting
Other recruiting trials for Metastatic Breast Cancer
Currently open trials in the same condition.
- NCT07524855 — A Study of HLD-0117 in Patients With Metastatic Breast Cancer · Phase 1 · recruiting
- NCT07408089 — Study of the Kinesin Oral Molecular Degrader BBI-940 in Subjects With Advanced or Metastatic Breast Cancer · Phase 1 · recruiting
- NCT07340541 — Evolutionary Clinical Trial for Novel Biomarker-Driven Therapies · Phase 2 · recruiting
- NCT07233928 — Breast Cancer Organelle Properties and Protein Expression Atlas in the Three Immunohistochemical Subtypes of Breast Canc · NA · recruiting
- NCT07347600 — A Study to Evaluate the Effectiveness and Safety of Inavolisib in Participants With Endocrine-resistant, PIK3CA-mutated, · recruiting
Other Memorial Sloan Kettering Cancer Center trials
Trials by the same sponsor.
- NCT07566377 — Cord Blood Transplantation in Children and Young Adults With Blood Cancer · Phase 2 · recruiting
- NCT07507643 — A Study of Methylprednisolone in People Having Liver Surgery · Phase 3 · recruiting
- NCT07483307 — A Study of the Impact of Endocrine Therapy on Surgical Outcomes in People With Breast Cancer · Phase 2 · recruiting
- NCT07459673 — HERizon-Breast: A ctDNA-Guided Adaptive Study of Sequential Anti-HER2 Therapies and CNS Prophylaxis to Induce Long-Term · Phase 2 · recruiting
- NCT07449195 — A Study Comparing Two Optical Coherence Tomography Devices in People With Ocular Tumors · NA · recruiting
Verify against primary sources
- ClinicalTrials.gov — authoritative US registry record
- WHO ICTRP — international registry index
- EU Clinical Trials Register
- Sponsor press releases (Google)
- Trial protocol + status: ClinicalTrials.gov NCT04872608 (US National Library of Medicine, public domain)
- Publications: Europe PMC API search by NCT ID, retrieved 10 June 2026
- Drug + disease cross-links: matched in real time against Drug Landscape's normalised drug + company + condition tables
- Sponsor: as reported to ClinicalTrials.gov by Memorial Sloan Kettering Cancer Center
- Last refreshed: 28 April 2023
Drug Landscape aggregates and links these public records for informational use only. Always verify against the primary source before clinical or regulatory decisions. Canonical URL: https://druglandscape.com/trial/NCT04872608.
Primary sources · FDA · ClinicalTrials.gov · EMA · SEC EDGAR · ChEMBL · Wikidata · full sourcing