A Study to Assess Safety, Tolerability, and Pharmacokinetics of ABSK112 in Patients With Non-Small Cell Lung Cancer

1. Patients should understand, sign, and date the written informed consent form prior to screening. 2. Male or female aged 18 years or older. 3. Patients with histologically or cytologically confirmed locally advanced (and not a candidate for definitive therapy) or metastatic NSCLC. 4. Cohort-specific inclusion criteria: 1. For the escalation part (except for the RDE confirmation part), patients have progressed on, rejected, or are intolerant of standard therapy, or for whom no standard therapy exists 2. For RDE confirmation in the escalation part: same as Cohort 1 in the expansion part 3. For the expansion part, patients have documented EGFR in-frame exon 20 insertion mutations confirmed by certificated local laboratories; and must also meet all criteria for the cohort in which their entry is proposed. 5. Patients must have at least one measurable target lesion according to RECIST v1.1 6. ECOG performance status 0 or 1 7. 7\. Life expectancy ≥3 months 8. Adequate organ function and bone marrow function. 9. Electrolyte: magnesium within 0.85 to 1.25 × institutional normal limits, sodium ≥130 mmol/L, potassium within institutional normal limits 10. Adequately controlled blood pressure (BP) with or without antihypertensive medications, defined as BP ≤150/90 mmHg at screening and no change in antihypertensive medications within 1 week prior to the Cycle1 Day1. 11. For patients participating in food effect exploration part: 1. Be able to eat a standardized high-fat meal within 30 minutes 2. Be able to fast for 10 hours. 12. Non-surgically sterilized male or female patients of childbearing potential must agree to use highly effective methods of birth control during the study treatment and for approximately 6 months after the last dose of study drug. A condom is also required to be used by vasectomized men to prevent delivery of the drug via seminal fluid.

1. Known allergy or hypersensitivity to any component of the investigational product. 2. NSCLC patients with EGFR Cys797Ser (C797S) mutation. 3. Cohort-specific