Phase 1 Part:~Using the standard 3+3 design for dose escalation, the Phase 1 Part will evaluate the prespecified 6 sequential dose levels of 100 microgram (μg), 200 μg, 400 μg, 800 μg, 1600 μg, and 3200 μg of TSN222 as a single agent in subjects with advanced solid tumors or lymphomas.~The eligible subjects will receive TSN222 via i.t. injection on Days 1, 8 and 15 of every 28-day cycle until disease progression or unacceptable toxicity. The dose-limiting toxicity (DLT) observation period will be defined as the first 28 days after the first dose (i.e. the first cycle). Based on the standard 3+3 design, cohorts of 3 to 6 subjects each will be sequentially assigned to the predefined dose levels. Dose escalation will continue until up to the highest planned dose or the MTD or RP2D is determined.~Phase 2 Part:~Phase 2 part will evaluate the efficacy and safety of TSN222 as monotherapy at the preliminary RP2D(s) in 3 cohorts bellow:~Cohort 1: advanced squamous cell carcinoma of head and neck (HNSCC). Cohort 2: advanced melanoma. Cohort 3: advanced other types of solid tumors or lymphomas.
The study is a first-in-human [FIH], open-label phase 1/2 study of TSN222 in subjects with advanced solid tumors or lymphomas. This study is comprised of a Phase 1 dose escalation and Phase 2 dose expansion component.