Background and Objective <p>D-1553 (garsorasib) is a novel and selective oral KRAS^G12C inhibitor. This study aims to evaluate the effect of food on the single-dose pharmacokinetics (PK) of D-1553 tablet in healthy Chinese subjects. Also the safety and tolerability of single-dose D-1553 in subjects are also evaluated.</p> Methods <p>A randomized, open-label, single-dose, two-intervention (fed vs fasting), two-period, two-sequence crossover study was performed on 14 healthy Chinese subjects. Plasma concentrations of D-1553 were determined by the liquid chromatography-tandem mass spectrometry method. Safety evaluations were carried out during the study period. The main PK parameters of the two formulations of D-1553 were calculated by non-compartmental analysis using Phoenix WinNonlin (Version 8.3) software.</p> Results <p>The geometric mean ratios (90% confidence interval [CI]) of AUC_0-t and AUC_0-∞ in the high-fat meal condition versus the fasting condition were 86.19% (78.30%, 94.87%) and 83.30% (75.77%, 91.58%), respectively. The geometric mean ratio (90% CI) of <i>C</i>_max values in high-fat meal condition to that observed in fasting condition were 109.74% (100.22%,120.15%). The <i>p</i> value of <i>T</i>_max was 0.1484 (fed vs fasting). Two subjects (14.3%) reported 4 treatment-emergent adverse events (TEAEs) in the fasting condition, and no subjects reported TEAEs in the fed condition. All adverse reactions were mild and had recovered by the end of the study.</p> Conclusion <p>The study indicated that a high-calorie and high-fat meal has no clinically relevant impact on the PK and bioavailability of D-1553 in healthy Chinese subjects. D-1553 was generally safe and well-tolerated under both fasting and fed conditions. The findings suggest that D-1553 could be administered orally with or without food.</p> Clinical Trials <p>ClinicalTrials.gov Identifer CTR20212761; registered on 4 Nov 2021.</p>