Abstract / Summary
Background: Severe hepatotoxicity has been reported when sotorasib follows immune checkpoint inhibitor (ICI) therapy, and fixed washout intervals have been proposed. We assessed prior ICI exposure and the ICI-to-sotorasib interval as separate risk factors. Materials and methods: We searched PubMed, Europe PMC, Embase, Web of Science, Scopus, CENTRAL, and meeting proceedings for comparative studies of grade 3 or higher hepatotoxicity after KRAS G12C inhibitors. Matched risk ratios (RRs) and unadjusted cohort data were synthesized separately, the latter with an exact conditional odds ratio (OR). Certainty was rated with GRADE. Results: Of 530 unique records screened, seven sources were included, all involving sotorasib. In the only matched analysis (meeting abstract, 386 patients per arm), prior ICI exposure was associated with higher risk (13.2% vs 4.4%, RR 3.00, 95% CI 1.76-5.10), whereas matched comparisons at 6 weeks (RR 1.11, 0.61-2.03) and 12 weeks (RR 1.08, 0.52-2.27) detected no difference but could not exclude important effects. All five unadjusted cohorts showed higher risk with shorter intervals, including 21/74 versus 8/75 patients in the earlier versus later interval quartiles of the CodeBreaK 200 trial, although effect sizes were heterogeneous (exact homogeneity P=0.006). Certainty was very low throughout. Conclusions: Prior ICI exposure was associated with higher risk of severe sotorasib-associated hepatotoxicity, with very low certainty. A shorter interval was associated with higher risk in unadjusted data only, and current evidence does not establish a mandatory washout period. Liver-test monitoring per the prescribing information applies to all patients, whereas additional surveillance after ICI exposure remains an untested precaution.