Ifinatamab Deruxtecan Granted Breakthrough Therapy Designation 

Ifinatamab deruxtecan (I-DXd) has been granted Breakthrough Therapy Designation (BTD) by the U.S. Food and Drug Administration (FDA) to treat adult patients with extensive-stage small cell lung cancer with disease progression on or after platinum-based chemotherapy.

Ifinatamab deruxtecan is a specifically engineered, potential first-in-class B7-H3 directed DXd antibody drug conjugate (ADC) discovered by Daiichi Sankyo. It is being jointly developed by Daiichi Sankyo and Merck (known as MSD outside of the United States and Canada).

This is the first BTD for ifinatamab deruxtecan and represents the first BTD since the start of the Daiichi Sankyo and Merck collaboration.

The FDA granted the BTD based on data from the IDeate-Lung01 phase 2 trial, with support from the IDeate-PanTumor01 phase 1/2 trial. Results from the primary analysis of IDeate-Lung01 will be presented at the IASLC 2025 World Conference on Lung Cancer hosted by the International Association for the Study of Lung Cancer.

“This Breakthrough Therapy Designation granted by the FDA to ifinatamab deruxtecan highlights the urgent need for new treatment options for patients with pretreated extensive-stage small cell lung cancer,” said Ken Takeshita, MD, Global Head, R&D, Daiichi Sankyo. “We are committed to advancing this medicine with the goal of bringing the first B7-H3 directed antibody drug conjugate to patients in order to transform the outcomes of those facing this aggressive disease.”