Daiichi Sankyo (TSE: 4568) and Merck, known as MSD outside of the United States and Canada, (NYSE: MEK) announced today that the U.S. Food and Drug Administration (FDA) has accepted and granted Priority Review to the Biologics License Application (BLA) for patritumab deruxtecan (HER3-DXd) for the treatment of adult patients with locally advanced or metastatic EGFR-mutated non-small cell lung cancer (NSCLC) previously treated with two or more systemic therapies.
The Prescription Drug User Fee Act (PDUFA) date, the FDA action date for their regulatory decision, is June 26, 2024. The Priority Review follows receipt of Breakthrough Therapy Designation granted by the FDA in December 2021.
The FDA grants Priority Review to applications for medicines that, if approved, would offer significant improvements over available options by demonstrating safety or efficacy improvements, preventing serious conditions or enhancing patient compliance. The BLA is being reviewed under the Real-Time Oncology Review (RTOR) program, an initiative of the FDA which is designed to bring safe and effective cancer treatments to patients as early as possible. RTOR allows the FDA to review components of an application before submission of the complete application.
Patritumab deruxtecan is a specifically engineered potential first-in-class HER3 directed DXd antibody drug conjugate (ADC) discovered by Daiichi Sankyo and being jointly developed and commercialized by Daiichi Sankyo and Merck.
The BLA is based on the primary results from the HERTHENA-Lung01 pivotal phase 2 trial and data results presented at the IASLC 2023 World Conference on Lung Cancer (#WCLC23), which were simultaneously published in the Journal of Clinical Oncology.
In HERTHENA-Lung01, patritumab deruxtecan was studied in 225 patients with EGFR-mutated locally advanced or metastatic NSCLC following disease progression with an EGFR TKI and platinum-based chemotherapy, which demonstrated an objective response rate (ORR) of 29.8% (95% CI: 23.9-36.2), including one complete response and 66 partial responses. The median duration of response was 6.4 months (95% CI: 4.9-7.8). The safety profile of patritumab deruxtecan observed in HERTHENA-Lung01 was consistent with previous phase 1 clinical trials in NSCLC with a treatment discontinuation rate of 7.1% due to treatment-emergent adverse events (TEAEs). Grade 3 or higher TEAEs occurred in 64.9% of patients. The most common (≥5%) grade 3 or higher TEAEs were thrombocytopenia (21%), neutropenia (19%), anemia (14%), leukopenia (10%), fatigue (6%), hypokalemia (5%) and asthenia (5%). Twelve patients (5.3%) had confirmed treatment-related interstitial lung disease (ILD) as determined by an independent adjudication committee. One grade 5 ILD event was observed.
“The FDA’s prioritization of the BLA submission reflects the strength of the data from HERTHENA-Lung01 and emphasizes the need to provide new options to patients with locally advanced or metastatic EGFR-mutated non-small cell lung cancer previously treated with two or more systemic therapies,” said Ken Takeshita, MD, Global Head, R&D, Daiichi Sankyo. “If approved, patritumab deruxtecan could become the first HER3 directed medicine approved in the US and the second DXd antibody drug conjugate approved from Daiichi Sankyo’s oncology pipeline.”
“The acceptance of the BLA submission of patritumab deruxtecan marks an important step in potentially bringing this new medicine to previously treated patients with EGFR-mutated non-small cell lung cancer who often experience recurrence and have few remaining treatment options,” said Marjorie Green, MD, Senior Vice President and Head of Late-Stage Oncology, Global Clinical Development, Merck Research Laboratories. “Today is the first of many important milestones from our collaboration with Daiichi Sankyo, as we work together to bring new and potentially first-in-class antibody drug conjugates to people living with cancer.”
