# Enhertu plus pertuzumab approved in the US as first-line treatment for HER2-positive metastatic breast cancer

Canonical page: https://technooptimist.io/stories/enhertu-plus-pertuzumab-approved-in-the-us-as-first-line-treatment-for-b68a6253
Date: 10 Dec 2025
About: [Daiichi Sankyo](https://technooptimist.io/companies/daiichi-sankyo.md) · [Enhertu](https://technooptimist.io/biotech/enhertu.md)
Original source: https://www.biospace.com/press-releases/enhertu-plus-pertuzumab-approved-in-the-u-s-as-first-new-treatment-in-more-than-a-decade-for-first-line-treatment-of-patients-with-her2-positive-metastatic-breast-cancer

The FDA approved Enhertu with pertuzumab as the first treatment for HER2-positive metastatic breast cancer, the first new first-line option in more than a decade. In DESTINY-Breast09 the combination kept cancer from growing for a median 40.7 months versus 26.9 months on the long-standing standard of taxane chemotherapy, trastuzumab and pertuzumab.

## Key facts

- 1,157 patients; progression-free survival HR 0.56 (44% lower risk of progression or death).
- Complete responses 15% vs 8%.
- Lung inflammation in 12% of patients on the combination, fatal in 0.5%.
- Triggers a $150M milestone from AstraZeneca to Daiichi Sankyo.

---

The Techno Optimist tracks every frontier of technology, program by program: https://technooptimist.io/ (a Markdown version of any page: add .md to its URL; site map for agents: https://technooptimist.io/llms.txt).
Data API (JSON, realtime stream): https://technooptimist.io/developers. People read 5 pages free, then Reader $10/month; these Markdown pages are open to agents.