July 22, 2021 – Arvinas, Inc. and Pfizer Inc. (New York, NY) announced a global collaboration to develop and commercialize ARV-471, an investigational oral PROTAC (PROteolysis TArgeting Chimera) estrogen receptor protein degrader.
The estrogen receptor is a well-known disease driver in most breast cancers, Pfizer says. ARV-471 is currently in a Phase 2 dose expansion clinical trial for the treatment of patients with estrogen receptor (ER) positive / human epidermal growth factor receptor 2 (HER2) negative (ER+/HER2-) locally advanced or metastatic breast cancer.
The agreement is a worldwide co-development and co-commercialization collaboration. ARV-471 is wholly owned by Arvinas and under the financial terms of the agreement, Pfizer will pay Arvinas $650 million upfront. Separately, Pfizer will invest $350 million in Arvinas, receiving approximately 3.5 million newly issued shares of Arvinas common stock, priced at a 30% premium to the 30-day volume weighted average price on July 20, 2021. This represents an equity ownership stake by Pfizer of approximately 7%.
Arvinas is also eligible to receive up to $400 million in approval milestones and up to $1 billion in commercial milestones, in addition to sharing profits on ARV-471 worldwide.
ARV-471 currently is being evaluated as a treatment for metastatic breast cancer in a Phase 1 dose escalation study, a Phase 1b combination study with Pfizer’s IBRANCE (palbociclib), and a Phase 2 monotherapy dose expansion study (VERITAC).
Arvinas and Pfizer expect to initiate two additional trials of ARV-471 in 2021, including a second Phase 1b combination trial with everolimus and a trial in the neoadjuvant setting.
In 2022, Arvinas and Pfizer expect to initiate Phase 3 studies across lines of therapy in metastatic breast cancer, including combinations with IBRANCE, followed by pivotal studies in the early breast cancer setting.
The two companies had previously announced in 2018 a separate research collaboration and license agreement for the discovery and development of drug candidates using Arvinas’ PROTAC technology.