Trends in historical response rates: A meta-analysis of KRAS G12C inhibitors in pretreated metastatic pancreatic cancer—Effects on ORR and disease control.

Abstract

e16443 Background: Pancreatic ductal adenocarcinoma (PDAC) remains one of the most lethal malignancies, with KRAS mutations present in approximately 90% of cases. Patients with advanced or metastatic PDAC who have progressed after standard chemotherapy face limited treatment options, with historical outcomes showing objective response rates (ORR) below 10% and median progression-free survival (PFS) and overall survival (OS) of approximately 2-4 months and 6-8 months, respectively. The development of covalent KRAS G12C inhibitors—including sotorasib, adagrasib, garsorasib, glecirasib, and divarasib—has opened new therapeutic options for this molecularly defined subset of PDAC patients. Methods: We conducted a systematic review and meta-analysis of clinical trials evaluating KRAS G12C inhibitor monotherapy in patients with advanced/metastatic pancreatic ductal adenocarcinoma. Data were extracted from 3 studies (Strickler 2022, Li J 2025, and Tanios 2023) encompassing a total of 91 patients with KRAS G12C-mutant PDAC who had received 1-2 prior lines of chemotherapy. Pooled estimates were calculated using random-effects meta-analysis models (DerSimonian-Laird method). For proportion outcomes (ORR and DCR), standard errors were calculated using binomial distribution, and for continuous outcomes (PFS and OS), inverse-variance weighting was employed. Heterogeneity was assessed using the I² statistic and Cochran's Q test. All confidence intervals were calculated at the 95% level. Results: The pooled analysis revealed clinically meaningful efficacy across all endpoints. The pooled objective response rate (ORR) was 32.9% (95% CI: 17.0% to 48.9%), with moderate heterogeneity (I² = 64.0%). The pooled disease control rate (DCR) was substantially higher at 88.3% (95% CI: 80.5% to 96.1%), with low heterogeneity (I² = 27.7%), indicating consistent disease stabilization across studies. For survival outcomes, the pooled median progression-free survival (PFS) was 4.98 months (95% CI: 3.62 to 6.34 months), with low heterogeneity (I² = 32.3%). The pooled median overall survival (OS) was 8.73 months (95% CI: 6.07 to 11.39 months), though with substantial heterogeneity (I² = 77.0%). Conclusions: KRAS G12C inhibitor monotherapy demonstrates clinically significant and durable efficacy in pretreated adults with advanced/metastatic PDAC harboring the KRAS G12C mutation. The pooled ORR of approximately one-third, together with a DCR near 90%, indicates substantial tumor control in a population with historically poor outcomes. Median PFS of approximately 5 months and OS of nearly 9 months represent clinically relevant improvements over standard salvage therapies, supporting KRAS G12C inhibitors as a viable option after chemotherapy failure.