“A phase I trial found that the HER2 inhibitor ONT-380 had a lower incidence of certain adverse events associated with this class of agent and notable anti-tumor activity in heavily pretreated patients with HER2-positive metastatic breast cancer (MBC).
” ‘Though existing targeted therapies are improving outcomes in patients with HER2-positive MBC, disease resistance does eventually develop in most patients,’ wrote study authors led by Stacy Moulder, MD, of the MD Anderson Cancer Center in Houston. Also, some agents preclude combination with other regimens due to off-target effects such as skin rash and diarrhea.”
“A prospective study is investigating whether breast cancer surgery can be eliminated in patients who respond well to neoadjuvant systemic therapy.
“The phase II single-center trial, conducted out of The University of Texas MD Anderson Cancer Center (NCT02945579), aims to determine how often breast cancer recurs in patients who previously received chemotherapy and follow-up radiation therapy, but not surgery, and have no evidence of disease. Forty patients with early-stage, triple-negative or HER2-positive breast cancer care underwent image-guided biopsy after completing chemotherapy and before beginning radiation therapy to see if surgery is necessary.”
“Data from the phase II PERTAIN trial presented late last year at the 2016 San Antonio Breast Cancer Symposium (SABCS) showed that adding an aromatase inhibitor (AI) to pertuzumab (Perjeta) and trastuzumab (Herceptin) extended progression-free survival (PFS) by over 3 months versus trastuzumab plus an AI in patients with HER2-positive, HR-positive locally advanced or metastatic breast cancer.
“The median PFS was 18.89 months with the pertuzumab triplet compared with 15.80 months for trastuzumab and an AI alone (HR, 0.65; 95% CI, 0.48-0.89; P = .007). The objective response rates were 63.3% versus 55.7%, respectively.”
“The Fc-modified monoclonal antibody margetuximab in combination with chemotherapy may offer a new treatment option for patients with HER2-positive metastatic breast cancer.
“In the ongoing phase III SOPHIA trial (NCT02492711), researchers are comparing margetuximab plus chemotherapy with trastuzumab (Herceptin) plus chemotherapy. In a previous phase I study, margetuximab demonstrated single-agent activity in HER2-positive tumors, leading researchers to explore the regimen in the phase III trial.”
“Brain metastases from primary breast cancer tumors often acquire clinically actionable genetic alterations, according to a small study. About one fifth of ERBB2/HER2-negative cases switched to HER2-positivity in the brain metastases.
” ‘Limited therapeutic options exist for patients with brain metastases,’ wrote study authors led by Nolan Priedigkeit, BS, of the University of Pittsburgh. ‘ERBB2/HER2-positive brain metastases have demonstrated encouraging responses to ERBB2/HER2-targeted therapies in recent clinical trials.’ ERBB2/HER2-negative brain metastases, however, have shown no such response.”
University of Colorado Cancer Center | Jan 10, 2017
“Phase 1 clinical trial data published this week in the journal Clinical Cancer Research show early promise of the investigational anti-cancer agent tucatinib (formerly ONT-380) against HER2+ breast cancer. The 50 women treated had progressed despite a median 5 previous treatment regimens. Twenty-seven percent of these heavily pretreated patients saw clinical benefit from the drug, with at least ‘stable disease’ at 24 or more weeks after the start of treatment. These data have led to two subsequent Phase Ib studies, resulting in tucatinib earning FDA fast-track status and the expansion of this study once meant only to demonstrate drug safety into the “pivotal” trial that will determine approval.”
“Adding a drug to a standard regimen for hormone receptor (HR)-positive and HER2-positive breast cancer improved progression-free survival, a researcher said here.
“In a Phase II randomized trial, investigators compared an aromatase inhibitor (AI) combined with pertuzumab (Perjeta) and trastuzumab (Herceptin) versus an AI just with trastuzumab in women with locally advanced or metastatic breast cancer, Grazia Arpino, MD, PhD, of the University of Naples Federico II in Italy, reported at a general session at the San Antonio Breast Cancer Symposium.
“The three-drug combination led to a median of 18.89 months without progression, compared with 15.8 months for the two drugs.”
“Breast cancer patients sometimes end up dying when their tumors spread all the way to the brain. Some very good drugs already exist for patients with breast cancer, especially ones with tumors that overexpress the HER2 marker, but that success has raised a new question: Can drugmakers take another step, and fight those deadly brain metastases that get people in the end?
“Seattle-based Cascadian Therapeutics is testing that idea this week with researchers gathered at the San Antonio Breast Cancer Symposium. Cascadian is reporting today that patients who got conventional capecitabine and trastuzumab, plus an experimental small-molecule drug, tucatinib (aka ONT-380), lived a median of 7.8 months without their tumors getting worse. About 61% of patients on that triple-drug combo saw tumors shrink. It’s an impressive result, given that these patients were especially ill when they enrolled in the study, having already received a median of three prior rounds of HER2-targeted therapy. The data are also holding up over time: a snapshot of the data from June showed patients living a median of 6.3 months without their tumors spreading.”
“A novel HER2-targeting antibody-drug conjugate showed promising antitumor activity across multiple tumor types, including HER2-postive breast cancer, according to phase I data presented at the 2016 ESMO Congress.
” ‘Antibody-drug conjugates represent promising drugs with a wider therapeutic window by effecting efficient and specific drug delivery to oncogene expressing tumor cells,’ explained lead author Kenji Tamura, MD, PhD, chairman, Department of Breast and Medical Oncology, National Cancer Center Hospital, Tokyo, Japan.”