NEW YORK – Daiichi Sankyo said on Wednesday that it has dosed the first EGFR-mutated, advanced non-small cell lung cancer patient with patritumab deruxtecan in the Phase II HERTHENA-Lung01 trial.
HERTHENA-Lung01 will enroll up to 420 previously treated patients with EGFR-mutated metastatic or locally advanced NSCLC in two arms to determine dosage. The primary endpoint for the trial is objective response rate. Participants must have been previously treated with an EGFR tyrosine kinase inhibitor and chemotherapy.
Patritumab deruxtecan is a HER3-directed antibody-drug conjugate. Previous research has found that 25 percent to 30 percent of lung cancers worldwide have an EGFR-activating mutation and about 83 percent of NSCLC tumors express the HER3 protein.
Preliminary results published in September from a Phase I trial of patritumab deruxtecan showed a 25 percent objective response rate in patients with EGFR-mutated NSCLC and a median duration of response of 7 months.
"Our focus is to rapidly and strategically advance the clinical development program of patritumab deruxtecan in cancers where HER3 is frequently overexpressed and is associated with poor prognosis," Gilles Gallant, global head of oncology development for oncology R&D at Daiichi Sankyo, said in a statement. "This study will further inform whether targeting HER3 with an antibody-drug conjugate may become a potential treatment strategy to overcome diverse mechanisms of EGFR TKI and chemotherapy resistance seen in patients with metastatic EGFR-mutated non-small cell lung cancer."
Daiichi Sankyo is also evaluating patritumab deruxtecan in combination with osimertinib (AstraZeneca's Tagrisso) in EGFR-mutated NSCLC, as well as exploring the drug's activity in colorectal and breast cancer.