A Study of IDE849 in Patients With DLL3 Expressing Tumors Including Small Cell Lung Cancer

This multicenter, open-label, Phase 1/2 study is designed to further characterize the safety, tolerability, pharmacokinetics (PK), immunogenicity, and preliminary anti-tumor activity of IDE849, an anti-DLL3 antibody-drug conjugate, alone and in combination with durvalumab or IDE161, in subjects with DLL3-expressing tumors including small-cell lung cancer (SCLC), high-grade neuroendocrine carcinomas (NEC), and other DLL3-positive solid tumors. Part 1 (Dose Escalation): Part 1A will evaluate IDE849 monotherapy, and Part 1B will evaluate IDE849 in combination with durvalumab or IDE161. This phase is designed to assess safety and tolerability, identify dose-limiting toxicities (DLTs), and determine the maximum tolerated dose (MTD) and recommended dose for expansion (RDE), in subjects with extensive-stage SCLC, high-grade NEC, or other DLL3-expressing tumors. Part 2 (Dose Expansion): Part 2 further will evaluate IDE849 alone or in combination at selected dose levels to characterize safety, PK, immunogenicity, and preliminary anti-tumor activity in defined cohorts of subjects with extensive-stage SCLC, high-grade NEC, or other DLL3-expressing tumors.