Background: c-MET (hepatocyte growth factor (HGF) receptor) overexpression, either by gene amplification, or mutation is associated with oncogenic transformation in numerous malignancies including lung, gastric, skin, renal, colorectal, and pancreatic cancers. ABN401 inhibits the activation of c-MET by reversibly interfering with the binding of c-Met tyrosine kinase to adenosine triphosphate (ATP) and blocking the receptor's downstream signaling that has demonstrated efficacy in NSCLC and gastric cancer in mouse xenograft and PDx models. This clinical trial is in progress in patients with advanced cancers. Methods: ABN401 is being evaluated in an open-label, non-randomized, dose-escalation (phase 1) study in patients with advanced solid tumors, and dose-expansion (phase 2) in patients with targeted indications and c-MET biomarker expression (NCT04052971). The phase 1 explores ascending daily doses of oral ABN401 monotherapy in 21-day cycles to identify the maximum tolerated dose (MTD) and recommended Phase 2 dose (RP2D). A preplanned extension (pilot expansion) study has been initiated based on predefined positive efficacy signals at intermediate doses up to 10 NSCLC patients who have c-MET alteration. Once RP2D is determined, the phase 2 expansion of up to 10-29 patients in four specific tumor-type cohorts is planned, utilizing a Simon's optimal two-stage design to evaluate the clinical activity of ABN401. ABN401-001 study began enrolling patients in August 2019 and is ongoing in Korean and Australia. Dose escalation up to cohort 4 has been completed, enrollment to cohort 5 began in November 2020. AEs are assessed according to CTCAE v5. Tumor response is determined according to RECIST 1.1 criteria and safety findings reviewed by the DRC, which will determine the RP2D and MTD. Key Phase 1 eligibility criteria include 1) histological or cytological diagnosis of melanoma or any type of carcinoma or sarcoma and 2) refractory metastatic disease, or refractory locally advanced disease not amenable to local therapy. For the extension (pilot expansion) study, patients must have NSCLC with MET exon 14 skipping, MET amplification and/or c-MET overexpression. An exploratory study is being conducted for co-development of a companion diagnostic (CDx) system including a CTC device and ddPCR kit through liquid biopsy. Clinical trial information: NCT04052971