To Evaluate the Efficacy of QLH11811 in Advanced NSCLC Patients With EGFR Mutation

"In Ia phase, subjects will first receive oral single dose of QLH11811, then will be observed for 7 days. If the drug is tolerated by the subjects, the subjects will continue to receive the oral repeat dose of QLH11811 for 21 consecutive days. Upon the completion of observation for DLT in the subjects (DLT observation period is the 28 days after the first dose), the subjects will continue to receive the repeat dose of QLH11811 in Cycle 2 and subsequent cycles. The dosing frequency in Cycle 2 and subsequent cycles is once daily, and each cycle has 3 weeks.~The RP2D of QLH11811 is determined on the basis of comprehensive evaluation of all safety and tolerability data and all available PK, PD and efficacy data during the dose escalation phase. In phase 1b, the cohort expansion study is carried out for all cohorts in China and the United States concurrently according to the determined RP2D."