Background: SH-1028 is a new third-generation EGFR tyrosine kinase inhibitors (TKI) to benefit patients with EGFR T790M-mutated NSCLC. Here, the authors report its clinical safety, preliminary efficacy, and pharmacokinetic (PK) profile for the first time.Methods: Patients with EGFR T790M mutation, locally advanced non-small cell lung cancer (NSCLC), or metastatic NSCLC who had progressed after previous EGFR TKI therapy were eligible. Patients received SH-1028 at five oral dose levels (60 mg, 100 mg, 200 mg, 300 mg, and 400 mg) once daily until disease progression, unacceptable toxicity, or patient withdrawal. The primary end points were the safety, dose-limiting toxicity (DLT), maximum-tolerated dose (MTD), and PK profile. Secondary end points included objective response rate (ORR), disease control rate (DCR), progression-free survival (PFS), etc.Results: Data cut off on December 31, 2020, a total of 20 patients were enrolled during the trial, two of three patients in 300 mg cohort experienced a DLT, and no DLT was observed in 240 mg cohort, 240 mg was determined to be the MTD of SH-1028. A total of 95.0% (19 of 20) of patients reported treatment-related adverse events (TRAEs), and the incidence of serious adverse events was 20.0% (4 of 20).The ORR and DCR of the 200 mg cohort were 75% (95% confidence interval [CI],19.41-99.37) and 75.0% (95% CI, 19.41-99.37), respectively. The overall ORR was 40% (95% CI, 19.12-63.95), and DCR was 70.0% (95% CI,). According to the PK profile, the dosage regimen for future studies was determined as 200 mg once daily.Conclusions: SH-1028 showed a manageable safety and promising antitumor activity in patients with EGFR T790M mutation at the dose of 200 mg once daily.The first two authors contributed equally to this article. The trial registration is ClinicalTrials.gov ID: NCT03603262.