The European Medicines Agency's Committee for Medicinal Products for Human Use (CHMP) has recommended approval for Enhertu (trastuzumab deruxtecan) in the treatment of unresectable or metastatic HER2-positive breast cancer, marking a significant milestone for Daiichi Sankyo and AstraZeneca's collaborative efforts.
The recommendation follows successful market entries in the United States and Japan, where Enhertu has already secured regulatory approvals based on compelling phase 2 DESTINY-Breast01 trial results. The study, involving 184 patients, demonstrated remarkable efficacy with a 61% tumor response rate in previously treated patients.
Clinical Performance and Market Position
Enhertu's commercial trajectory shows promising momentum, with revenues reaching $136 million in the first nine months of 2020, including $60 million in the third quarter alone. The drug has established itself as the preferred treatment option for third-line and fourth-line HER2-positive metastatic breast cancer settings.
The innovative antibody-drug conjugate combines the targeting mechanism of trastuzumab with a potent topoisomerase inhibitor, specifically designed to deliver cytotoxic therapy to cancer cells while minimizing impact on healthy tissue. This approach is particularly crucial for HER2-positive breast cancer patients, who represent approximately 20% of breast cancer cases and face more aggressive disease progression and higher mortality risks.
Therapeutic Landscape and Competition
Enhertu positions itself as an advanced alternative for patients who have progressed on established HER2-targeted therapies, including Roche's Herceptin, Perjeta, and Kadcyla. While Kadcyla, another antibody-drug conjugate, achieved blockbuster status, it fell short of expectations in pivotal trials for earlier treatment lines.
Strategic Expansion Plans
Daiichi Sankyo and AstraZeneca are pursuing an ambitious development program for Enhertu, with plans to expand into additional indications. The FDA is currently reviewing its application for HER2-positive gastric cancer, with a decision expected in early 2021. The companies are also exploring its potential in HER2-positive non-small cell lung cancer and investigating its use in tumors with lower HER2 expression levels.
Commercial Outlook
Industry analysts project Enhertu to rapidly achieve $2 billion in annual sales, with Daiichi Sankyo forecasting peak sales potential of $4.5 billion. The drug's promise is reflected in AstraZeneca's substantial investment, including a $1.35 billion upfront payment as part of a potential $6.9 billion licensing agreement signed in late 2019.
