NEW YORK – Effector Therapeutics on Tuesday said it is working with Stanford Medicine to study the activity of its eIF4A inhibitor zotatifin in patients with estrogen receptor (ER)-positive, HER2-negative breast cancer.
The investigator-initiated Phase II study will be led by Jennifer Caswell-Jin, assistant professor of medicine at Stanford Medicine. Researchers will enroll ER-positive, HER2-negative patients two weeks before surgery to receive either zotatifin plus fulvestrant or fulvestrant alone. The primary endpoint of the trial is to assess change in tumor proliferative status, which researchers will measure by performing Ki67 testing at baseline and 14 days after preoperative treatment.
Researchers are interested in zotatifin's efficacy in certain genomically defined subgroups of ER-positive, HER2-negative breast cancer patients, including those at standard risk and high risk for disease relapse. Patients at high risk of relapse will include those with tumors overexpressing cyclin D1, fibroblast growth factor 1 (FGFR1), or FGFR3. Researchers led by Christina Curtis, professor of medicine, genetics, and biomedical data science at Stanford, previously identified these high-risk breast cancer subtypes.
"This investigator-led study presents a unique opportunity to complement Effector's existing development strategy with cutting-edge expertise in next-generation genomic predictive technologies to continue exploring the clinical potential of zotatifin for treating breast cancer," Doug Warner, chief medical officer at Effector, said in a statement.
Warner added that the trial launched with Stanford complements Effector's ongoing efforts to explore zotatifin's activity in metastatic ER-positive breast cancer and highlighted the firm's multi-biomarker approach to identifying best responders, as opposed to using a single genetic marker as is typical. "Current targeted therapies fail too many patients, and we hope this collaboration will help identify better treatment regimens with improved clinical benefit for patients," he said.
Effector, based in Solana Beach, California, is also studying zotatifin in a Phase I/II trial in patients with hormone receptor (HR)-positive breast cancer and KRAS-mutated non-small cell lung cancer.