“There is an urgent need for new, safe and efficacious therapies to treat ER+/HER2- breast cancer, particularly when standard of care regimens fail,” said Dr. Mark Bray, Treadwell CSO and Co-founder.  “CFI-402257 has shown early signs of durable activity with a manageable safety profile, as a monotherapy and in combination with fulvestrant in ER+/HER2- breast cancer patients that have failed CDK4/6 inhibitors.  We are thankful for the Fast Track Designation granted by the FDA and look forward to the continued development of CFI-402257 in ER+/HER2- breast cancer.”