Study of RET Inhibitor TAS0953/HM06 in Patients With Advanced Solid Tumors With RET Gene Abnormalities

Ages Eligible for Study: \- Adult patient (The definition of adulthood shall comply with the regulatory requirements of each region) Inclusion Criteria: Phase I - Common inclusion criteria for Dose-Escalation / Dose-Expansion: * Eastern Cooperative Oncology Group (ECOG) performance score of 0 or 1 * Available RET-gene abnormalities determined on tissue biopsy or liquid biopsy. If deemed appropriate by the investigator, determination on a pleural cell block or cell pellet is also acceptable. * Adequate hematopoietic, hepatic and renal function Phase I Dose-Escalation - Specific inclusion criteria: * Advanced solid tumors * Measurable and/or non-measurable disease as determined by RECIST 1.1 * If patient has brain and/or leptomeningeal metastases, (s)he should be asymptomatic. Phase I Dose-Expansion - Specific inclusion criteria: * Patient with RET gene fusion : * Cohort 1, 3: locally advanced or metastatic NSCLC patients naïve to RET selective inhibitors and no prior systemic anti-cancer treatment. Patients who have been treated with neo-adjuvant or adjuvant chemotherapy may be included if it has been completed at least 6 months prior to the first dose of the study. * Cohort 2, 4: locally advanced or metastatic NSCLC patients with RET gene fusion and prior exposure to RET selective inhibitors. * Measurable disease as determined by RECIST 1.1 * If patient has brain and/or leptomeningeal metastases,(s)he should have: * asymptomatic untreated brain/leptomeningeal …