Globenewswireยท2025-09-02 11:00Core Viewpoint - Olema Pharmaceuticals has announced a new clinical trial collaboration with Pfizer to evaluate the combination of palazestrant and atirmociclib in treating metastatic breast cancer, aiming to establish palazestrant as a potential backbone endocrine therapy [1][2] Group 1: Clinical Trial Collaboration - The collaboration involves a Phase 1b/2 study to assess the safety and combinability of palazestrant and atirmociclib in patients with ER+/HER2- metastatic breast cancer [1][2] - Pfizer will supply atirmociclib for the study, while Olema will lead the trial [2] - This marks Olema's second clinical trial agreement with Pfizer, following a previous agreement in November 2020 [3] Group 2: Product and Pipeline Information - Olema's lead product candidate, palazestrant (OP-1250), is an orally available complete estrogen receptor antagonist and selective ER degrader, currently in a Phase 3 trial called OPERA-01 [4][5] - Palazestrant has received FDA Fast Track designation for treating ER+/HER2- metastatic breast cancer that has progressed after endocrine therapy [5] - The company is also developing OP-3136, a KAT6 inhibitor, which is in a Phase 1 clinical study [4] Group 3: Future Plans and Expectations - The new study is expected to involve approximately 35 patients, with initiation anticipated in the second half of 2025 [6] - Successful results from this study could inform a pivotal Phase 3 trial for the combination therapy in the frontline metastatic breast cancer setting [6]