- VERITAC-2 achieved its primary endpoint in the estrogen receptor 1-mutant population, demonstrating statistically significant and clinically meaningful improvement in progression-free survival -
- Vepdegestrant is the first PROTAC degrader to demonstrate clinical benefit
in a Phase 3 trial -
NEW HAVEN, Conn. and NEW YORK, March 11, 2025 - Arvinas, Inc. (Nasdaq: ARVN) and Pfizer Inc. (NYSE: PFE) today announced positive topline results from the Phase 3 VERITAC-2 clinical trial (NCT05654623) evaluating vepdegestrant monotherapy versus fulvestrant in adults with estrogen receptor-positive, human epidermal growth factor receptor 2-negative (ER+/HER2-) advanced or metastatic breast cancer whose disease progressed following prior treatment with cyclin-dependent kinase (CDK) 4/6 inhibitors and endocrine therapy. These are the first pivotal data for vepdegestrant, a potential first-in-class investigational oral PROteolysis TArgeting Chimera (PROTAC) ER degrader.
The trial met its primary endpoint in the estrogen receptor 1-mutant (ESR1m) population, demonstrating a statistically significant and clinically meaningful improvement in progression-free survival (PFS) compared to fulvestrant. The results exceeded the pre-specified target hazard ratio of 0.60 in the ESR1m population. The trial did not reach statistical significance in improvement in PFS in the intent-to-treat (ITT) population.
"The first Phase 3 data readout for a PROTAC degrader represents a significant achievement and these data show that vepdegestrant has the potential to provide clinically meaningful outcomes for thousands of patients with metastatic breast cancer whose tumors harbor estrogen receptor 1 mutations," said John Houston, Ph.D., Chairperson, Chief Executive Officer and President at Arvinas. "We want to thank the patients and investigators who participated in this trial, and we look forward to sharing these data with health authorities as well as at a medical conference in 2025."
Overall survival was not mature at the time of the analysis, with less than a quarter of the required number of events having occurred. The trial will continue to assess overall survival as a key secondary endpoint. In the trial, vepdegestrant was generally well tolerated and its safety profile was consistent with what has been observed in previous studies. Detailed results from VERITAC-2 will be submitted for presentation at a medical meeting later this year, and these data will be shared with global regulatory authorities to potentially support regulatory filings.
"Patients with advanced ER+/HER2- metastatic breast cancer face significant clinical challenges, with limited treatment options following disease progression and the development of resistance to available endocrine therapies," said Megan O'Meara, M.D., Interim Chief Development Officer, Pfizer Oncology. "These data from VERITAC-2 support the potential of vepdegestrant to give patients whose tumors harbor ESR1 mutations additional time without disease progression, compared to fulvestrant."
Vepdegestrant is an investigational oral PROTAC ER degrader for ER+/HER2- breast cancer being jointly developed by Arvinas and Pfizer and is designed to harness the body's natural protein disposal system to specifically target and degrade the ER. In February 2024, the companies announced that the U.S. Food and Drug Administration (FDA) granted Fast Track designation for the investigation of vepdegestrant for monotherapy in the treatment of adults with ER+/HER2- advanced or metastatic breast cancer previously treated with endocrine-based therapy.
About Metastatic Breast Cancer
About 2.3 million new breast cancer diagnoses were reported globally in 2022,1 and it is estimated there will be nearly 320,000 people diagnosed with breast cancer in the U.S. in 2025.2 Estrogen receptor-positive, human epidermal growth factor receptor 2-negative (ER+/HER2-) breast cancer accounts for approximately 70% of all cases.3
Nearly 30% of women initially diagnosed with early-stage breast cancer will ultimately develop metastatic breast cancer (MBC),4 the most advanced stage in which the disease has spread beyond the breast to other parts of the body. Treatment advances have helped those with MBC better manage symptoms, slow tumor growth, and may allow them to live longer, but most patients ultimately develop resistance to current standard-of-care treatments in the first-line setting and experience disease progression. ESR1 mutations are a common cause of acquired resistance and are found in approximately 40% of patients in the second-line setting.5 6 7
About the VERITAC-2 Clinical Trial
The Phase 3 VERITAC-2 clinical trial ( NCT05654623 ) is a global randomized study evaluating the efficacy and safety of vepdegestrant (ARV-471) as a monotherapy compared to fulvestrant in patients with ER+/HER2- advanced or metastatic breast cancer. The trial enrolled 624 patients at sites in 26 countries who had previously received treatment with a CDK4/6 inhibitor plus endocrine therapy.
Patients were randomized to receive either vepdegestrant once daily, orally on a 28-day continuous dosing schedule, or fulvestrant, administered intramuscularly on Days 1 and 15 of Cycle 1 and then on Day 1 of each 28-day cycle starting from Day 1 of Cycle 2. The primary endpoint was progression-free survival (PFS) in the intent-to-treat and ESR1m populations as determined by blinded independent central review. Overall survival is a key secondary endpoint.
About Vepdegestrant
Vepdegestrant is an investigational, orally bioavailable PROTAC (PROteolysis TArgeting Chimera) protein degrader designed to specifically target and degrade the estrogen receptor (ER) for the treatment of patients with ER-positive (ER+)/human epidermal growth factor receptor 2 (HER2)-negative (ER+/HER2-) breast cancer. Vepdegestrant is being developed as a potential monotherapy and as part of combination therapy across multiple treatment settings for ER+/HER2- metastatic breast cancer.
In July 2021, Arvinas announced a global collaboration with Pfizer for the co-development and co-commercialization of vepdegestrant; Arvinas and Pfizer will share worldwide development costs, commercialization expenses, and profits.
The U.S. Food and Drug Administration (FDA) has granted vepdegestrant Fast Track designation as a monotherapy in the treatment of adults with ER+/HER2- advanced or metastatic breast cancer previously treated with endocrine-based therapy.
About Arvinas
