Study of D3L-002 in Subjects With Advanced Solid Tumors

This is a first-in-human, multicenter, open-label, single-arm, dose-escalation Phase 1 study evaluating the safety, tolerability, pharmacokinetics, pharmacodynamics, immunogenicity, and preliminary antitumor activity of D3L-002 monotherapy in subjects with advanced solid tumors. D3L-002 will be administered as an intravenous infusion every 3 weeks (Q3W) in 21-day cycles. Approximately 24 subjects will be enrolled. Dose escalation will follow a Bayesian Optimal Interval (BOIN) design to determine the maximum tolerated dose (MTD) and recommended Phase 2 dose (RP2D).

Inclusion Criteria: 1. Ability to provide written informed consent and comply with study procedures 2. Age ≥18 years 3. Histologically confirmed metastatic or locally advanced incurable solid tumor that has progressed after ≥1 line of therapy or has no available standard treatment 4. Eastern Cooperative Oncology Group (ECOG) performance status 0-1 5. Adequate organ function (hematologic, hepatic, renal) 6. Life expectancy ≥12 weeks 7. Willingness to provide tumor tissue (if available) and blood samples 8. Agreement to use effective contraception 9. Negative pregnancy test for participants of childbearing potential Exclusion Criteria: 1. Prior anti-TIGIT or anti-PVRIG therapy 2. Recent anticancer therapy without adequate washout 3. Active or uncontrolled illness 4. Interstitial lung disease/pneumonitis 5. Active Central Nervous System (CNS) disease 6. Uncontrolled effusions 7. Unresolved ≥Grade 2 toxicities 8. Severe prior immunotherapy-related toxicity 9. Active autoimmune disease 10. Active infection 11. Active hepatitis B/C or HIV 12. Recent malignancy (exceptions apply) 13. Significant cardiovascular disease 14. Immunosuppressive therapy within 14 days 15. Live vaccine within 30 days 16. Pregnancy or breastfeeding 17. Hypersensitivity to study drug 18. Investigator-determined unsuitability