The U.S. Food and Drug Administration (FDA) has granted Priority Review to I-DXd, an investigational antibody-drug conjugate, for the treatment of extensive-stage small cell lung cancer (ES-SCLC), according to regulatory filings. The designation shortens the review timeline to six months, with a decision expected by late 2024.
I-DXd, developed by Daiichi Sankyo, targets delta-like ligand 3 (DLL3), a protein overexpressed in SCLC tumors. The Priority Review is based on Phase 2 trial data showing improved progression-free survival compared to standard therapies. Analysts note this could address a critical unmet need, as ES-SCLC has limited treatment options and poor survival rates.
“The FDA’s action reflects the urgent need for effective therapies in this aggressive cancer,” said an oncologist familiar with the trial, who spoke anonymously due to ongoing research. Small cell lung cancer accounts for 10%-15% of all lung cancers, with most cases diagnosed at the extensive stage.
If approved, I-DXd would join a competitive landscape including Roche’s Tecentriq and AstraZeneca’s Imfinzi. However, its novel mechanism—delivering chemotherapy directly to DLL3-positive cells—could differentiate it. Market analysts project annual sales exceeding $1 billion if clinical benefits hold in Phase 3 trials.