Patritumab deruxtecan gains FDA Breakthrough status

The US Food and Drug Administration has granted Breakthrough Therapy designation (BTD) to patritumab deruxtecan (HER3-DXd), a potential first-in-class HER3 directed antibody drug conjugate (ADC) from Japan’s Daiichi Sankyo (TYO: 4568), for the treatment of patients with metastatic or locally advanced EGFR-mutated non-small cell lung cancer (NSCLC) with disease progression on or after treatment with a third-generation tyrosine kinase inhibitor (TKI) and platinum-based therapies.

Lung cancer is the second most common cancer and the leading cause of cancer-related mortality worldwide, with 80% to 85% classified as NSCLC. While the efficacy of targeted therapy with EGFR TKIs is well-established in the treatment of advanced EGFR-mutated NSCLC, which comprises approximately 30% of patients, the development of a broad range of resistance mechanisms commonly leads to disease progression. After failure of an EGFR TKI, platinum-based chemotherapy has limited efficacy with progression-free survival (PFS) of approximately 4.4 to 6.4 months. Subsequent salvage therapies after EGFR TKI and platinum-based chemotherapy have PFS of 2.8 to 3.2 months.

Daiichi Sankyo is also evaluating patritumab deruxtecan in combination with osimertinib, AstraZeneca's (LSE: AZN) Tagrisso, in EGFR-mutated NSCLC, as well as exploring the drug's activity in colorectal and breast cancer.