OncoMatch

OncoMatch/Clinical Trials/NCT05904964

Disitamab Vedotin (RC48) in Hormone Receptor Positive, HER2-low Metastatic Breast Cancer (the Rosy Trial)

Is NCT05904964 recruiting? Yes, currently enrolling (May 2026). This Phase 3 trial studies Disitamab vedotin for hr positive/her2 low expression metastatic breast cancer.

Phase 3RecruitingSun Yat-Sen Memorial Hospital of Sun Yat-Sen UniversityNCT05904964Data as of May 2026

Treatment: Disitamab vedotinHormone receptor positive, HER2-low expression metastatic breast cancer is the main type of breast cancer, accounting for about 50% - 60%. However, this type of patients lack ideal therapeutic drugs after the failure of first-line standard endocrine therapy, and the median overall survival time is only 30 months. Therefore, finding more efficient and safe therapeutic drugs for these patients has become a big clinical challenge at present. Disitamab Vedotin (DV), as a new class I Antibody-Drug Conjugates drug, can achieve high efficiency and precise tumor killing effect with low toxicity. According to previous study with same sample size, DV also showed good efficacy in metastatic breast cancer with Hormone receptor positive and HER2- low expression as a posterior line treatment.Therefore, we intend to explore the efficacy and safety of DV in the treatment of HER2-low expressioin /Hormone receptor positive metastatic breast cancer patients with endocrine resistance through a scientifically designed, randomized, phase III clinical study.

Check if I qualify

Extracted eligibility criteria

Cancer type

Breast Carcinoma

Biomarker criteria

Required: ESR1 overexpression (IHC ≥ 10%)

ER expression: immunohistochemical staining of tumor cells ≥ 10%

Required: PR (PGR) overexpression (IHC ≥ 10%)

PR expression: immunohistochemical staining of tumor cells ≥ 10%

Required: HER2 (ERBB2) low expression (IHC 2+ and FISH not amplified, or IHC 1+)

HER2-low: immunohistochemical staining of 2 + and FISH is not expanded, IHC 1 +

Disease stage

Metastatic disease required

Performance status

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

Prior therapy

Min 1 prior line

Must have received: endocrine therapy

Patients who have received endocrine therapy

Cannot have received: chemotherapy

Exception: within 2 weeks before enrollment

Patients who had received chemotherapy ... within 2 weeks before enrollment

Cannot have received: radiotherapy

Exception: within 2 weeks before enrollment

Patients who had received ... radiotherapy ... within 2 weeks before enrollment

Cannot have received: immunotherapy

Exception: within 2 weeks before enrollment

Patients who had received ... immunotherapy ... within 2 weeks before enrollment

Cannot have received: endocrine therapy

Exception: within 2 weeks before enrollment

Patients who had received ... endocrine therapy ... within 2 weeks before enrollment

Lab requirements

Blood counts

WBC ≥ 3.0 × 10^9/L; ANC ≥ 1.5 × 10^9/L; PLT ≥ 70 × 10^9/L

Kidney function

serum creatinine ≤ 1.5 × ULN or creatinine clearance rate (CCR) ≥ 60 ml / min

Liver function

total bilirubin (TBIL) ≤ 1.5 × ULN; ALT/AST ≤ 2.5 × ULN (liver metastasis patients ≤ 5xULN)

Cardiac function

LVEF ≥ 55%, QTcF ≤ 470 ms

Adequate bone marrow functional reserve ... Liver, kidney and heart function tests were basically normal within one week before enrollment

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

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