FDA cleared Veppanu on Friday as the first-ever PROTAC therapy, a new drug class that actively degrades disease-causing proteins rather than just blocking them. The target: ER-positive, HER2-negative advanced breast cancer with ESR1 mutations in patients who’ve already failed endocrine therapy.
PROTAC stands for proteolysis-targeting chimera. Veppanu is a small molecule with two functional sites: one binds the estrogen receptor, the other recruits the cell’s own degradation machinery. The result is widespread estrogen receptor degradation, disrupting cancer cells’ ability to proliferate.
The data picture isn’t clean. The VERITAC-2 Phase 3 trial showed a 43% reduction in the risk of disease progression or death versus AstraZeneca’s Faslodex in a June 2025 readout. But the intent-to-treat analysis, covering all randomized patients, failed to hit statistical significance on both the March 2025 topline and the June follow-up. Overall survival data was immature at filing.
FDA cleared it anyway.
That’s the precedent here. The agency greenlit a new drug class on data that couldn’t survive ITT scrutiny. Every other PROTAC program in oncology just got a data point to study.
Pfizer bought into Veppanu in July 2021 for $650 million upfront, a $350 million equity stake, and up to $1.4 billion in milestones.
Commercialization isn’t settled. Pfizer and Arvinas still haven’t named a third-party partner to sell the drug. It’s Arvinas’ first FDA approval, with Truist forecasting $1.1 billion in peak sales by 2036.
Sarah Chen