The antibody–drug conjugate ifinatamab deruxtecan (I-DXd) has shown clinically meaningful responses in pretreated patients with extensive-stage small cell lung cancer (ES-SCLC), according to an interim analysis of the Phase 2 IDeate-Lung01 study. The data was presented today at the International Association for the Study of Lung Cancer (IASLC) 2024 World Conference on Lung Cancer . Patients with ES-SCLC face poor outcomes and have limited treatment options .
B7 homolog 3 (B7-H3 [CD276]) is part of the B7 family, which includes immune checkpoint proteins such as PD-L1. B7-H3 is highly expressed in many solid tumors but is absent or expressed at low levels in normal tissues. High and consistent expression of B7-H3 has been shown across all molecular subtypes of SCLC and has been linked to poor prognosis.
I-DXd, a B7-H3–directed antibody–drug conjugate, demonstrated promising efficacy in the ongoing Phase 1/2 IDeate-Pantumor01 study, with a confirmed objective response rate (ORR) of 52.4% and a median duration of response (DOR) of 5.9 months in the SCLC cohort (n=22).
In the dose optimization part of the ongoing Phase 2 IDeate-Lung01 study, two doses of I-DXd (8 mg/kg and 12 mg/kg IV every 3 weeks) were evaluated in patients with ES-SCLC who had received at least one prior line of platinum-based chemotherapy and no more than three prior lines of systemic treatment. Patients with asymptomatic brain metastases could participate in the study. The primary endpoint was ORR by b.