COLUMBUS, Ohio, and SAN FRANCISCO, Nov. 02, 2024 (GLOBE NEWSWIRE) — Sermonix Pharmaceuticals Inc., a privately held biopharmaceutical company developing innovative therapeutics to specifically treat metastatic breast cancers (mBC), and Quantum Leap Healthcare Collaborative™ today broadly announced that in the Phase 2 clinical trial evaluating lasofoxifene as a neoadjuvant endocrine therapy in molecularly selected HR+/HER2-, locally advanced breast cancer, the investigational drug was well tolerated and demonstrated promising early activity in suppressing the Ki67 protein in both premenopausal and postmenopausal patients.
Results from the study, an arm of the Endocrine Optimization Pilot Protocol (EOP), a sub-study of Quantum Leap’s ongoing I-SPY 2 TRIAL (Investigation of Serial studies to Predict Your Therapeutic Response with Imaging And moLecular analysis 2), were initially shared yesterday in a poster presentation at RISE UP for Breast Cancer.
Twenty patients (10 pre- and nine postmenopausal women, and one male) were enrolled in the lasofoxifene arm of the study, during which early Ki67 suppression in premenopausal patients was seen in the absence of ovarian function suppression (OFS). Ki67 is a marker that measures how fast cancer cells are dividing.
“Lasofoxifene continued to demonstrate a strong tolerability profile while showing promising Ki67 suppression in this Phase 2 study, supporting our plans to further explore its potential in the neoadjuvant setting,” said Dr. David Portman, Sermonix founder and chief executive officer. “We are currently studying lasofoxifene in the ELAINE-3 Phase 3 combination study with abemaciclib in the ESR1-mutated metastatic breast cancer setting. We are excited to see it continue to demonstrate broad potential while offering unique quality of life benefits for people confronted with breast cancer.”
Patients were enrolled in the I-SPY 2 arm from March 2023 to May 2024. Median total days of treatment was 154 days. At the time of data analysis, three patients were still on treatment and two discontinued treatment due to physician or patient preference.
Median Ki67 expression went from 10% at baseline (range 1.0-40%) to 4% (1.0-18.0%) at Week 3. At three weeks, Ki67 expression was suppressed to
