9556 Background: Preliminary tepotinib data showed durable activity in pts with NSCLC with METex14 skipping prospectively identified by liquid (L+) or tissue (T+) biopsy. Having met target enrollment of ≥60 L+ pts & ≥60 T+ pts, we report primary data. Methods: VISION Cohort A enrolled pts with advanced EGFR/ALK wt, METex14 skipping NSCLC (asymptomatic brain metastases [BM] allowed), who received oral tepotinib 500 mg QD. On-study treatment decisions were based on investigator assessment (INV) of response. Primary endpoint was objective response rate (ORR) by independent review committee (IRC) analyzed in 3 primary ITT sets: L+ and/or T+, L+, T+. 2ary endpoints included ORR by INV, duration of response (DOR), disease control rate (DCR), PFS, OS, & safety. Preplanned analyses were performed in pts with BM at baseline (BL). BL/on-treatment ctDNA plasma samples (L+) were analyzed using a 73-gene NGS panel (Guardant360). Deep molecular responses (MR), defined as > 75% depletion of METex14, were compared with objective responses (OR). Results: By data cut-off (1 Oct 19) 151 pts received tepotinib (safety set); 99 L+/T+, 66 L+, 60 T+ pts comprised the 3 ITT sets with ≥6-month [m] follow-up. Across treatment lines (n = 44 1L, n = 55 ≥2L), primary ORR & mPFS [95% CI] in 99 L+/T+ pts were 43% [34–54] & 8.6 m [6.9–11.0] by IRC and 56% [45–66] & 9.5 m [6.7–13.5] by INV. ORR was similar in L+ or T+ pts (table) or in T+L− pts (n = 25): 40% [21–61] by IRC and 48% [28–69] by INV. Only 2 pts were T−L+. Outcomes were also comparable in pts with BM (n = 11): IRC ORR 55% [23–83] & mPFS 10.9 m [8.0–ne]. 34/51 pts (67%) with matched BL/on-treatment L+ samples had deep MR strongly associated with clinical response: 32/34 pts (94%) with MR had disease control (INV), including 29/34 pts (85%) with OR; 2/34 pts had progressive disease. Further biomarker data will be presented. Grade ≥3 treatment-related adverse events (TRAEs) were reported by 37/151 pts (25%). 13 pts (9%) discontinued due to TRAEs. Conclusions: Tepotinib is a promising targeted therapy with durable clinical activity and manageable toxicity in pts with METex14 skipping NSCLC L+ or T+, including pts with BM. High ORR & DCR in pts with ctDNA molecular responses support that MET inhibition in METex14+ tumor cells can lead to clinical benefit. Clinical trial information: NCT02864992 . [Table: see text]
9012 Background: In the VISION study, tepotinib in METex14 skipping NSCLC pts (Cohort A) had robust and durable clinical activity. Serial LBx samples were collected for biomarker analyses, presented herein. Methods: LBx samples taken at baseline (BL), Week 6, 12, & end of treatment (EOT) were analyzed using Guardant360 ® CDx (73 genes). Investigator (INV)-assessed clinical outcome was evaluated per BL biomarker profiles and by molecular response (MR; defined as > 75% depletion from BL in METex14 variant allele frequency [VAF] ctDNA confirmed in 2 consecutive samples) or molecular progression (MP; defined as VAF increase > 0 from BL). Acquired resistance was investigated in EOT samples, following progression per INV. Results: LBx pts (n = 99) had a median age of 72 yrs (range 49–88), 53% were male, 44% never smokers, 85% had adenocarcinoma. INV ORR was 53% (95% CI 42, 63); ORR in 1L (n = 44) was 59% (43, 74) & ≥2L (n = 55) was 47% (33, 61). 94 pts had BL biomarker profiles; these were similar in 1L and ≥2L pts, except EGFR amp: 1/43 1L [2%] vs 8/51 ≥2L [16%]. Outcomes were not impacted by location/type of METex14 alteration. 1 pt with concomitant MET M1250T mutation had a PFS of 17.3 months. A trend towards better efficacy was seen in pts with concomitant MET amp (6 responses in 8 pts). Response to tepotinib occurred both in pts with wt or mutant TP53; however, there was a trend for longer mDOR in pts with wt TP53 (18.3 [95% CI 9.7, ne] vs 7.1 [4.7, 10.9] months) and mPFS (9.5 [6.7, 19.7] vs 5.1 [2.8, 6.9] months). Concomitant oncogenic mutations were rare, with no responses in 3 pts with KRAS, NRAS alterations and 3 responses in 5 pts with PI3K/AKT alterations. 65 pts had 2 consecutive on-treatment samples: 46 (71%) had confirmed MR, 5 (8%) had confirmed MP, 14 (22%) had no change in VAF or lacked confirmation. MR was associated with clinical response and MP was associated with no response/short PFS (Table). 52 pts with progression had EOT LBx samples. Emerging MET resistance mutations (Y1230H/C & D1228H/N) occurred in 7 (13%) pts, all responders and 5/7 had PFS > 10 months. Analyses on non-MET-driven resistance mechanisms will be presented. Conclusions: LBx biomarker analysis from the largest on-treatment data set for a MET inhibitor in METex14 skipping NSCLC, showed that ctDNA depletion in METex14 VAF is associated with improved clinical response in pts treated with tepotinib. This suggests serial LBx could help us to monitor response/non-response, understand resistance, and guide trials that test escalation/de-escalation strategies to improve outcomes and maximize QOL. Clinical trial information: NCT02864992. [Table: see text]
The field of immunotherapy for non-small cell lung cancer (NSCLC) patients is in constant evolution, given that combinatorial treatment strategies flank anti-PD-1/PD-L1 monotherapy and disease settings beyond the advanced one derive benefit form immune checkpoint blockers (ICB). In this evolving scenario, the clinical experience derived from advanced NSCLC patients receiving single agent ICB will likely retain relevant meaning. In particular, treatment with PD-1/PD-L1 agents has been accompanied by the emergence of new patterns of clinico-radiological disease response, namely hyper-progression and pseudo-progression. Still harboring different prognostic implications, these two entities share some pathogenetic elements (both involving a dysregulated immune response) and, more importantly, the complexity of recognition and management. In this overview, we gather the evidence on the peculiar characteristics of hyper-progression and pseudo-progression in NSCLC. We aim to provide elements of current and future clinical interest and, moreover, to point out the relevance of getting more pathological and biological insights in these two entities, in order to improve their successful prediction and management.
Abstract Background About 10% of NSCLCs are mutated in KRAS and impaired in STK11/LKB1 , a genetic background associated with poor prognosis, caused by an increase in metastatic burden and resistance to standard therapy. LKB1 is a protein involved in a number of biological processes and is particularly important for its role in the regulation of cell metabolism. LKB1 alterations lead to protein loss that causes mitochondria and metabolic dysfunction that makes cells unable to respond to metabolic stress. Different studies have shown how it is possible to interfere with cancer metabolism using metformin and caloric restriction (CR) and both modify the tumor microenvironment (TME), stimulating the switch from “cold” to “hot”. Given the poor therapeutic response of KRAS mut / LKB1 mut patients, and the role of LKB1 in cell metabolism, we examined whether the addition of metformin and CR enhanced the response to chemo or chemo-immunotherapy in LKB1 impaired tumors. Methods Mouse cell lines were derived from lung nodules of transgenic mice carrying KRAS G12D with either functional LKB1 (KRAS G12D /LKB1 wt ) or mutated LKB1 (KRAS G12D /LKB1 mut ). Once stabilized in vitro, these cell lines were inoculated subcutaneously and intramuscularly into immunocompetent mice. Additionally, a patient-derived xenograft (PDX) model was established by directly implanting tumor fragments from patient into immunocompromised mice. The mice bearing these tumor models were subjected to treatment with chemotherapy or chemo-immunotherapy, both as standalone regimens and in combination with metformin and CR. Results Our preclinical results indicate that in NSCLC KRAS mut / LKB1 mut tumors, metformin and CR do enhance the response to chemo and chemo-immunotherapy, inducing a metabolic stress condition that these tumors are not able to overcome. Analysis of immune infiltrating cells did not bring to light any strong correlation between the TME immune-modulation and the tumor response to metformin and CR. Conclusion Our in vitro and in vivo preliminary studies confirm our hypothesis that the addition of metformin and CR is able to improve the antitumor activity of chemo and chemoimmunotherapy in LKB1 impaired tumors, exploiting their inability to overcome metabolic stress.
Clinical data suggest that only a subgroup of non-small cell lung cancer (NSCLC) patients has long-term benefits after front-line platinum-based therapy. We prospectively investigate whether KRAS status and DNA polymerase β expression could help identify patients responding to platinum compounds. Prospectively enrolled, advanced NSCLC patients treated with a first-line regimen containing platinum were genotyped for KRAS and centrally evaluated for DNA polymerase β expression. Overall survival (OS), progression-free survival (PFS), and the objective response rate (ORR) were recorded. Patients with KRAS mutations had worse OS (hazard ratio (HR): 1.37, 95% confidence interval (95% CI): 0.70-2.27). Negative DNA polymerase β staining identified a subgroup with worse OS than patients expressing the protein (HR: 1.43, 95% CI: 0.57-3.57). The addition of KRAS to the analyses further worsened the prognosis of patients with negative DNA polymerase β staining (HR: 1.67, 95% CI: 0.52-5.56). DNA polymerase β did not influence PFS and ORR. KRAS may have a negative role in platinum-based therapy responses in NSCLC, but its impact is limited. DNA polymerase β, when not expressed, might indicate a group of patients with poor outcomes. KRAS mutations in tumors not expressing DNA polymerase β further worsens survival. Therefore, these two biomarkers together might well identify patients for whom alternatives to platinum-based chemotherapy should be used.
