Olema Oncology Announces New Clinical Trial Agreement with Pfizer to Combine Palazestrant with Atirmociclib in ER+/HER2- Metastatic Breast Cancer
Olema Oncology (Nasdaq: OLMA) has announced a new clinical trial collaboration with Pfizer (NYSE: PFE) to evaluate the combination of palazestrant and atirmociclib in patients with ER+/HER2- metastatic breast cancer.
The Phase 1b/2 study will assess the safety and combinability of Olema's palazestrant with Pfizer's investigational CDK4 inhibitor atirmociclib in approximately 35 patients, with trial initiation expected in H2 2025. Results will inform a potential pivotal Phase 3 trial in frontline metastatic breast cancer.
Under the agreement, Pfizer will supply atirmociclib while Olema leads the study. Both companies will jointly own clinical data and inventions, with Olema retaining full global commercial rights to palazestrant.
Olema Oncology (Nasdaq: OLMA) ha annunciato una nuova collaborazione clinica con Pfizer (NYSE: PFE) per valutare la combinazione di palazestrant e atirmociclib in pazienti con cancro mammario metastatico ER+/HER2-.
Lo studio di Fase 1b/2 verificherà sicurezza e compatibilità della combinazione tra il palazestrant di Olema e l'inibitore sperimentale CDK4 atirmociclib di Pfizer in circa 35 pazienti, con avvio previsto nel 2° semestre 2025. I risultati potranno indirizzare un possibile studio pivotale di Fase 3 in prima linea nel metastatico.
Secondo l’accordo, Pfizer fornirà atirmociclib mentre Olema condurrà lo studio. Entrambe le società deterranno congiuntamente i dati clinici e le invenzioni, mentre Olema manterrà i diritti commerciali globali sul palazestrant.
Olema Oncology (Nasdaq: OLMA) ha anunciado una nueva colaboración clínica con Pfizer (NYSE: PFE) para evaluar la combinación de palazestrant y atirmociclib en pacientes con cáncer de mama metastásico ER+/HER2-.
El estudio de Fase 1b/2 evaluará la seguridad y la posibilidad de combinar el palazestrant de Olema con el inhibidor CDK4 en investigación atirmociclib de Pfizer en aproximadamente 35 pacientes, con inicio previsto en el segundo semestre de 2025. Los resultados podrán servir de base para un posible estudio pivotal de Fase 3 en primera línea del metastásico.
Según el acuerdo, Pfizer suministrará atirmociclib y Olema dirigirá el estudio. Ambas compañías poseerán conjuntamente los datos clínicos y las invenciones, mientras que Olema retendrá los derechos comerciales globales sobre palazestrant.
Olema Oncology (Nasdaq: OLMA)는 Pfizer (NYSE: PFE)와 새로운 임상시험 협력을 발표했습니다. 양사는 palazestrant와 atirmociclib의 병용을 ER+/HER2- 전이성 유방암 환자에서 평가할 예정입니다.
이 1b/2상 연구는 Olema의 palazestrant와 Pfizer의 연구용 CDK4 억제제 atirmociclib의 안전성 및 병용 가능성을 약 35명의 환자에서 평가하며, 연구 시작은 2025년 하반기로 예정되어 있습니다. 결과는 전선 치료의 전이성 유방암에 대한 잠재적 3상 결정에 활용될 수 있습니다.
계약에 따라 Pfizer는 atirmociclib을 제공하고 Olema가 연구를 주도합니다. 양사는 임상 데이터와 발명을 공동 소유하며, Olema는 palazestrant에 대한 전 세계 상업화 권리를 보유합니다.
Olema Oncology (Nasdaq: OLMA) a annoncé une nouvelle collaboration clinique avec Pfizer (NYSE: PFE) pour évaluer la combinaison de palazestrant et d'atirmociclib chez des patientes atteintes de cancer du sein métastatique ER+/HER2-.
L'étude de Phase 1b/2 évaluera la sécurité et la compatibilité de la combinaison du palazestrant d'Olema avec l'inhibiteur CDK4 en développement atirmociclib de Pfizer chez environ 35 patientes, avec un démarrage prévu au second semestre 2025. Les résultats pourront orienter un éventuel essai pivot de Phase 3 en première ligne dans le métastatique.
Conformément à l'accord, Pfizer fournira atirmociclib et Olema dirigera l'étude. Les deux sociétés seront copropriétaires des données cliniques et des inventions, tandis qu'Olema conservera les droits commerciaux mondiaux sur le palazestrant.
Olema Oncology (Nasdaq: OLMA) hat eine neue klinische Studienkooperation mit Pfizer (NYSE: PFE) angekündigt, um die Kombination von palazestrant und atirmociclib bei Patientinnen mit ER+/HER2- metastasiertem Brustkrebs zu untersuchen.
Die Phase‑1b/2‑Studie wird die Sicherheit und Kombinierbarkeit von Olemas palazestrant mit Pfizers experimentellem CDK4‑Inhibitor atirmociclib bei etwa 35 Patientinnen prüfen; Studienstart ist für das 2. Halbjahr 2025 geplant. Die Ergebnisse sollen eine mögliche pivotale Phase‑3‑Studie in der Erstlinientherapie des metastasierten Tumors informieren.
Im Rahmen der Vereinbarung stellt Pfizer atirmociclib zur Verfügung, während Olema die Studie leitet. Beide Unternehmen werden klinische Daten und Erfindungen gemeinsam besitzen; Olema behält die weltweiten kommerziellen Rechte an palazestrant.
- New strategic collaboration with major pharmaceutical company Pfizer
- Potential pathway to Phase 3 trial in frontline metastatic breast cancer
- Company maintains full global commercial rights to palazestrant
- Expands development program with second Pfizer collaboration agreement
- None.
Insights
Olema's strategic partnership with Pfizer strengthens palazestrant's positioning as a potential backbone therapy for metastatic breast cancer.
This collaboration between Olema Oncology and Pfizer represents a significant development in the breast cancer treatment landscape. The planned Phase 1b/2 study will evaluate palazestrant (Olema's selective estrogen receptor degrader) with atirmociclib (Pfizer's selective CDK4 inhibitor) in approximately 35 patients with ER+/HER2- metastatic breast cancer.
The strategic importance of this agreement is multifaceted. First, it positions palazestrant to potentially become a backbone endocrine therapy in metastatic breast cancer treatment regimens if the trials prove successful. Second, this builds upon Olema's existing clinical program infrastructure, which includes the already-underway OPERA-01 pivotal study and the upcoming OPERA-02 ribociclib combination trial.
The terms of the agreement are favorable for Olema, as the company will maintain full global commercial rights to palazestrant while benefiting from Pfizer's supply of atirmociclib. Joint ownership of clinical data and inventions relating to the combined therapy preserves Olema's significant stake in the potential value created.
This marks Olema's second collaboration with Pfizer, following their November 2020 agreement to evaluate palazestrant with palbociclib (IBRANCE®), demonstrating continued confidence from a major pharmaceutical partner. For a clinical-stage company like Olema, these partnerships can provide validation of their technology while sharing the substantial costs of clinical development in the competitive oncology space.
- Study to explore the palazestrant-atirmociclib combination in approximately 35 patients with initiation anticipated in H2 2025
- Results to inform potential pivotal Phase 3 trial of novel combination in frontline metastatic breast cancer setting
SAN FRANCISCO, Sept. 02, 2025 (GLOBE NEWSWIRE) -- Olema Pharmaceuticals, Inc. (“Olema” or “Olema Oncology”, Nasdaq: OLMA), a clinical-stage biopharmaceutical company focused on the discovery, development, and commercialization of targeted therapies for breast cancer and beyond, today announced a new clinical trial collaboration and supply agreement with Pfizer Inc. (NYSE: PFE) in metastatic breast cancer. The companies will evaluate in a Phase 1b/2 study the safety and combinability of palazestrant plus atirmociclib, Pfizer’s investigational, highly selective-CDK4 inhibitor, in patients with estrogen receptor-positive, human epidermal growth factor receptor 2-negative (ER+/HER2-) metastatic breast cancer.
"We are excited to assess this combination in the clinic as we seek to establish palazestrant as a potential backbone endocrine therapy for metastatic breast cancer,” said Sean P. Bohen, M.D., Ph.D., President and Chief Executive Officer of Olema Oncology. “Based on the promising profiles of palazestrant and atirmociclib to date, we look forward to evaluating the potential of this novel combination and, if successful, advancing to a pivotal trial in the frontline setting. With OPERA-01, our first pivotal study of palazestrant, underway and our OPERA-02 ribociclib combination trial in frontline metastatic breast cancer anticipated to initiate this quarter, we remain focused on achieving our goal of transforming the metastatic breast cancer treatment paradigm.”
Under the terms of the agreement, Pfizer will supply atirmociclib for use in the Phase 1b/2 study and Olema will lead the conduct of the study. All clinical data and inventions relating to the combined use of atirmociclib and palazestrant resulting from the study will be jointly owned, with Olema maintaining full global commercial and marketing rights to palazestrant.
This announcement represents Olema’s second clinical trial agreement with Pfizer. The companies’ previous agreement was established in November 2020 to evaluate palazestrant in combination with palbociclib (IBRANCE®) in patients with recurrent, locally advanced or metastatic ER+/HER2- breast cancer.
About Olema Oncology
Olema Oncology is a clinical-stage biopharmaceutical company committed to transforming the standard of care and improving outcomes for patients living with breast cancer and beyond. Olema is advancing a pipeline of novel therapies by leveraging our deep understanding of endocrine-driven cancers, nuclear receptors, and mechanisms of acquired resistance. Our lead product candidate, palazestrant (OP-1250), is a proprietary, orally available complete estrogen receptor (ER) antagonist (CERAN) and a selective ER degrader (SERD), currently in a Phase 3 clinical trial called OPERA-01. In addition, Olema is developing OP-3136, a potent lysine acetyltransferase 6 (KAT6) inhibitor, now in a Phase 1 clinical study. Olema is headquartered in San Francisco and has operations in Cambridge, Massachusetts. For more information, please visit www.olema.com.
About Palazestrant (OP-1250)
Palazestrant (OP-1250) is a novel, orally available small molecule with dual activity as both a complete estrogen receptor (ER) antagonist (CERAN) and selective ER degrader (SERD). It is currently being investigated in patients with recurrent, locally advanced or metastatic ER-positive (ER+), human epidermal growth factor receptor 2-negative (HER2-) breast cancer. In clinical studies, palazestrant completely blocks ER-driven transcriptional activity in both wild-type and mutant forms of metastatic ER+ breast cancer and has demonstrated anti-tumor efficacy along with attractive pharmacokinetics and exposure, favorable tolerability, central nervous system penetration, and combinability with cyclin-dependent kinase 4/6 (CDK4/6) inhibitors. Palazestrant has been granted U.S. Food and Drug Administration (FDA) Fast Track designation for the treatment of ER+/HER2- metastatic breast cancer that has progressed following one or more lines of endocrine therapy with at least one line given in combination with a CDK4/6 inhibitor. It is being evaluated as a single agent in the ongoing pivotal Phase 3 clinical trial, OPERA-01 and is anticipated to be evaluated in combination with ribociclib in the planned pivotal Phase 3 clinical trial, OPERA-02. Learn more at www.opera01study.com. Palazestrant has also been evaluated in multiple Phase 1/2 studies in combination with ribociclib, palbociclib, alpelisib, and everolimus.
Forward Looking Statements
Statements contained in this press release regarding matters that are not historical facts are “forward-looking statements” within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934. Words such as “anticipate,” “believe,” “could,” “expect,” “goal,” “may,” “plan,” “potential,” “seek,” “upcoming,” “will,” and similar expressions (as well as other words or expressions referencing future events, conditions or circumstances) are intended to identify forward-looking statements. These statements include those related to the potential of palazestrant to become a backbone endocrine therapy for metastatic breast cancer, Olema’s potential to transform the metastatic breast cancer treatment paradigm, the timing for initiation, enrollment, and results of Olema’s existing and planned clinical trials, including OPERA-01 and OPERA-02, the potential beneficial characteristics, safety, tolerability, efficacy, and therapeutic effects of palazestrant as a single agent or in combination therapy, and the ownership of clinical data, commercial rights, marketing rights and inventions relating to the combined use of palazestrant and atirmociclib. Because such statements deal with future events and are based on Olema’s current expectations, they are subject to various risks and uncertainties, and actual results, performance or achievements of Olema could differ materially from those described in or implied by the statements in this press release. These forward-looking statements are subject to risks and uncertainties, including, without limitation, those discussed in the section titled “Risk Factors” in Olema’s Quarterly Report on Form 10-Q for the quarter ended June 30, 2025, and other filings and reports that Olema makes from time to time with the U.S. Securities and Exchange Commission. Except as required by law, Olema assumes no obligation to update these forward-looking statements, including in the event that actual results differ materially from those anticipated in the forward-looking statements.
Media and Investor Relations Contact
Courtney O’Konek
Vice President, Corporate Communications
Olema Oncology
media@olema.com
FAQ
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