# A Phase II Clinical Study of the Efficacy and Safety of Culmerciclib Rechallenge in HR-positive, HER2-negative Breast Cancer Patients With Resistance to First-line Endocrine Therapy.

> **NCT07666555** · PHASE2 · RECRUITING · sponsor: **Fudan University** · enrollment: 98 (estimated)

## Conditions studied

- Breast Cancer

## Interventions

- **DRUG:** CDK4/6 inhibitor
- **DRUG:** Culmerciclib
- **DRUG:** Fulvestrant

## Key facts

- **NCT ID:** NCT07666555
- **Lead sponsor:** Fudan University
- **Sponsor class:** OTHER
- **Phase:** PHASE2
- **Study type:** INTERVENTIONAL
- **Status:** RECRUITING
- **Start date:** 2026-06-06
- **Primary completion:** 2028-06-30
- **Final completion:** 2029-12-30
- **Target enrollment:** 98 (ESTIMATED)
- **Last updated:** 2026-06-24


## Primary source

ClinicalTrials.gov registry: https://clinicaltrials.gov/study/NCT07666555

## Citation

> US National Library of Medicine, ClinicalTrials.gov registration NCT07666555, "A Phase II Clinical Study of the Efficacy and Safety of Culmerciclib Rechallenge in HR-positive, HER2-negative Breast Cancer Patients With Resistance to First-line Endocrine Therapy.". Retrieved via MORVS 2026-10-20 from https://api.morvs.ai/clinical/NCT07666555. Licensed CC0.

---

*[Clinical trials dataset](/datasets/clinical-trials) · CC0 1.0*