HER2 Positive Breast Cancer

P3, N=541, Active, not recruiting, DualityBio Inc. | Recruiting --> Active, not recruiting

P=N/A, N=350, Suspended, City of Hope Medical Center | Initiation date: Jan 2026 --> May 2026

In vivo studies with immunocompromised mice bearing HER2-BM tumors demonstrated that M6 inhibits tumor growth and metastasis to the lungs, livers, and kidneys by ~90%, comparable to MBQ-167. These findings suggest that M6 exhibits potent anticancer properties both in vitro and in vivo, potentially contributing to the sustained efficacy of MBQ-167 in metastatic breast cancer.

NP-mediated delivery of a TLR2 inhibitor and doxorubicin produces synergistic anti-cancer effects in breast cancer models. This approach may help overcome chemoresistance and improve therapeutic outcomes, offering a promising strategy for the treatment of advanced breast cancer.

P1, N=27, Not yet recruiting, Baylor College of Medicine | Trial completion date: Sep 2034 --> Jan 2044 | Trial primary completion date: Sep 2028 --> Jan 2029

P1/2, N=22, Active, not recruiting, Fondazione Policlinico Universitario Agostino Gemelli IRCCS | Recruiting --> Active, not recruiting

Chidamide combined with fulvestrant showed encouraging antitumor activity and tolerable toxicity in pts with HR + /HER2- advanced breast cancer that had progressed after previous endocrine therapy. Trial registration ChiCTR2100044282, registered on March 14th 2021.

These findings suggest that ctDNA assessment at baseline may provide additional prognostic information to define the risk of patients after NST. While ctDNA shows promise in capturing tumor burden and biological characteristics, its role in predicting pCR and long-term outcomes requires further investigation.

Owing to active renal lesions, the patient was treated with prednisolone and cyclophosphamide, which resulted in clinical remission. This case was considered to have T-DM1-associated IgA vasculitis. Although rare, an awareness of the possibility of serious adverse effects associated with drug administration is important.

These data support T-DXd as a broadly efficacious treatment for patients with HR+, HER2-low/-ultralow mBC after ≥1 ET, regardless of TTP on prior first-line ET + CDK4/6i, endocrine resistance, or disease burden.

She received first-line chemotherapy with trastuzumab, pertuzumab, and docetaxel, followed by maintenance anti-HER2 therapy and surgery for local disease control. This case may represent an exceptional response to T-DM1 and highlights the potential for durable complete remission in selected patients with HER2-positive metastatic breast cancer. Further investigation is warranted to identify predictive factors for exceptional responses and to determine optimal treatment duration.